Oil & Natural Gas Corporation Ltd.
Mumbai Region, Engineering Services,
615, Vasudhara Bhavan Bandra (E)
Mumbai – 400 051
Tel.: 91-22- 2659 9677, 26599615 Fax: 91- 22- 26599677 / 26599500
e –mail : firstname.lastname@example.org
and Major repair cell
Sub : Asking ‘COMMENTS OR OBSERVATIONS’ from Well Proven
Manufacturers, packagers, regularly supplying skid mounted oil filled air
screw compressor and instrument air dryers for offshore oil & gas production
ONGC intends to replace the existing old four skid mounted packages of Utility air
(reciprocating type) compressors and instrument air dryer packages with skid mounted
Utility air screw (oil filled type) compressors and instrument air dryer packages at its WIN,
ICW, BPA & BPB offshore Gas – Oil platforms as per the enclosed Description of work ,
technical specifications and Data Sheets at Annexure I.
‘COMMENTS OR OBSERVATIONS’ are therefore sought by ONGC from Well Proven
Manufacturers, packagers for supplying on FOB basis, skid mounted oil filled air screw
compressor and instrument air dryers for offshore oil – gas production platforms. Removal
of existing packages and Installation of new packages shall be carried out separately.
Interested manufacturers, packagers, suppliers are requested to send their comments or
observations through e – mail / fax or letters at above address.
General Instructions to the prospective Bidders
The following shall be submitted/confirmed/presented by the Vendors in their ‘comments’
against the requirement mentioned above (as per the enclosed Description of work,
technical specifications and Data Sheets at Annexure I.)
1. Documentary proof of the credential in supplying the required packages as per scope
of work and specifications enclosed in Annexure I for Offshore Gas – Oil platforms.
2. Detailed Technical Catalogues/Literatures in respect of the offered comments and
confirmation on the adequacy of the space and other existing facilities at platforms for
installation of the packages.
3. Technical write-ups to support their comments.
4. Specific comments on deputation of OEM commissioning engineers at offshore
during installation and commissioning , which shall be arranged by installation
5. Any specific advice on the Data Sheets and Scope of work & Specifications /
adequacy of available space for installation of skid mounted air screw compressor
and dryer packages for ensuring better performance.
6. Bidders are requested to submit their comments by 24/4/05, after which comments
shall not be considered.
Encl.: Annexure I (28pages)
TECHNICAL SPECIFICATION AND
DESCRIPTION OF WORK
SUPPLY OF PACKAGES OF UTILITY AIR
SCREW COMPRESSOR AND
INSTRUMENT AIR DRYER SKIDS FOR
Oil and Natural Gas Corporation Ltd. requires 4 Nos. skid mounted new packages of
Instrument and Utility air screw compressors along with compatible and matching air dryer
units, associated equipments instrument, piping etc. on FOB basis for replacement of
existing packages on following Oil/Gas production platform/water injection offshore
platforms located in western offshore of India.
1. ICW platform - 2 Nos Air compressors and 1 no. Air drier
2. WIN platform - -do-
3. BPA platform - -do-
4. BPB platform - -do-
These units shall be installed and commissioned in the same space and location of the platform after removal of the
existing equipment. The job of removal of existing equipment, installation and commissioning at offshore platform
shall be carried out through a separate contract to be awarded by ONGC through competitive bidding.
2.SCOPE OF WORK
Bidder shall carry out design, manufacturer, inspection, testing, and supervision during installation & commissioning
and performance testing at platform in compliance with technical specifications, drawings, data sheets and P&IDs of
the package in the bidding document.
The interface engineering between the compressors and dryer shall be responsibility of bidder and he shall guarantee
outlet condition at skid battery limit. The material required for field installation job shall be covered in the scope of
This specification outlines the minimum requirement only for supply of new utility air
screw (oil filled type) compressors (one working + one standby) and instrument air dryer
package mounted on a skid for replacement of existing old package at following offshore
platforms as per attached specifications.
Platform / Equipment Differential Flow rate Dryer Existing skid size
oil field Tag Nos. Pressure Nm³ / Hr Capacity /available deck space
Kg/Cm²(g) Nm³ / Hr LxWxH in mm
ICW / C-5410/ 11.5 800 640 6400x3740x
WIN/ C-5410/ 9.5 800 640 7200x5200x
BPA/ C- 2550A/ 11.5 800 640 4700x3785x3500*
BPB/ C- 1070A/ 11.5 800 640 7000x3500x3500
* After extension of deck on east side, available deck space shall be 7000x4700x3500
2.1 Bidder is advised to make pre bid site survey to make himself fully aware with the scope of work,
adequacy of deck space, site conditions, material handling equipment facilities on board such as deck
crane, mono rails etc. including the availability and access to designated space and shall take care of
these aspects while designing & manufacturing the system. Bidder in case needs some
additional data/information on the skid, the same shall/can be collected by the
bidder from respective platform.
ONGC (company) intends to locate new package within the existing deck space only. Bidder shall
design the package keeping adequate provision for space required for operations and maintenance. No
additional space shall be available.
2.2 Bidders are advised to check the adequacy of deck space for locating new packages of the compressor
and dryer as per the requirement during pre bid survey and confirm the suitability in their bid
.Constraints if any shall be brought to notice of the company during pre bid meeting.
2.3 The package supplied by the bidder shall be skid mounted and some of the accessories may be supplied
loose if necessary to be installed at site as per the specifications and drawings. The installation shall be
carried out by the installation contractor under separate contract. The bidder shall submit installation
drawings of the skid for review of ONGC and the installation contractor which will be finally approved
by ONGC. The Installation contractor shall check and verify all the items for completeness of the
package as per specification before taking delivery from contractor/supplier. Transportation, insurance,
installation & commissioning shall be taken up by the installation contractor. Custom clearance of the
packages shall be carried out by Installation contractor and pay order for assessed custom duty
applicable on packages shall be arranged by ONGC to be given to installation contractor for payment
to the custom department.
2.4 Proper uniformity and standardisation shall be ensured while selection of make and model of various
equipment of the package.
2.5 Bidder shall design and supply a package considering that these skids shall be installed and
commissioned one after another or together at respective platforms if so desired by the Company.
Bidder shall design and supply equipment and material up to skid battery limit to facilitate hook up of
new package with the existing plant system including modification or any other work necessary for
integration with existing piping, electrical, instrumentation and control etc. to make the system
Adequate space and access shall be available within the skid to facilitate repair maintenance, cleaning
on compressors, compressor parts, air filters, coolers, loading and unloading of desiccant from adsorber
vessels and their components, parts and instrument with reasonable convenience.
2.6 Weather protective and sound attenuating painted carbon steel enclosure panels designed and
constructed for quick assembly and removable at site as per the operation and maintenance
requirements shall be provided for the compressor skids only for their protection from rain water and to
ensure sound levels as per specification. Ventilation and lighting shall be provided in side enclosure for
safe operation and convenient maintenance. Top side panel of skid enclosure shall be removable type
for operation of chain pulley block for removal and maintenance of equipments.
2.7 Bidder’s scope of supply shall include all new instruments and control items as per the specification
and selection of instrument as a minimum shall meet the requirements defined in enclosed Appendix 6
and Appendix 5. All instruments shall be suitable for use in humid and tropical offshore climate. All
necessary weather and anti corrosion protection to instruments shall be provided to prevent damage
from saline and corrosive process packages. These instrument shall be enclosed in suitable weather
proof Nema-4 x enclosures as minimum to protect them from site conditions specified in Appendix 1
of the tender specifications. All out door instruments shall as a minimum be suitable and certified for
hazardous area requirements specified elsewhere in the bidding document. For standardisation, make
and model of the instruments shall be approved by ONGC before procurement.
2.8 Bidders shall provide painting of equipment, piping valves, skid base and supports, ladders etc. of the
skid and other surfaces as per specifications included in the bidding documents. Bidders shall supply
and provide insulation required for personal protection and for repair of damage insulation where ever
2.9 Bidder shall provide commissioning spares required during pre-commissioning, commissioning of the
equipment at offshore. Bidder shall provide the list of commissioning spares included in the lump sum
quoted prices in his offer.
2.10 Bidder shall also supply mandatory spares as listed in bid specification and prices for the same shall be
quoted as optional in the price format. The prices for mandatory spares shall not be considered for
evaluation of the bid.
2.11 Bidders shall also furnish in their offer recommended list with itemised unit rates of one year
operational spares (valid for supply up to two years from the date of successful performance testing at
platform) to be ordered separately.
2.12 Bidder as minimum shall supply one set of following special tools & tackles for compressor and dryer
package within the quoted lump sum price
-Set of torque wrenches
-Portable hydraulic operated bearing puller for removal of bearings
-Sockets for removal of filter elements / cartridges
-Any other special tools & tackles required as per manufacturer’s
2.13 Any other work required for supply, commissioning, performance testing of new skid mounted
equipment, operation and smooth function of other associated facilities not specified specifically in this
specification but required for completion of the job shall be done by the bidder.
INSPECTION & PERFORMANCE TESTING
2.14 The bidder shall arrange inspection of the package equipment from reputed third
party inspection agency namely LRS, BV, DNV etc. or any other agency approved by the
company. Bidder shall also arrange the witness of the performance test of compressors by
third party inspection agency in the premises of manufacturer of screw compressor and air dryer.
Bidder shall bear the associated cost and expenses of third party inspection including their fee etc.
for the inspection of the packages.
2.15 Bidder shall furnish letter of commitment with the bid from respective equipment manufacturers
(compressor, dryer etc.) for providing services during installation and commissioning of the package at
each offshore platform. The cost towards this services shall be born by the installation contractor.
2.16 Bidder shall furnish letter of commitment from respective equipment manufacturers for providing after
sales service including supply of spares for a period of minimum fifteen years from the date of
commissioning of the equipment.
2.17 The bidder shall carry out procurement & manufacturing only after approval of design and engineering
by ONGC. Bidder shall submit all design data, design calculations and drawings for approval / review
by ONGC, same shall also be reviewed by installation contractor. Details of all documents to be
submitted shall be finalised during kick off meeting.
2.18 Bidder shall submit his schedule for design, engineering, procurement, fabrication, assembly,
inspection and supply of equipment.
2.19 Bidder shall furnish pre commissioning, commissioning checks and procedure for performance test to
be carried out at offshore platforms. Same shall be reviewed by ONGC and installation contractor. The
pre commissioning, commissioning and performance test shall be carried out in association with bidder
/ representatives of compressor & dryer. The cost towards associations of Bidder, OEM’s of
compressor and dryer shall be born by installation contractor.
2.20 Bidder shall provide their experience record for executing similar contracts for offshore requirement
and proposed organisation chart for the execution of such type of works along with bids for the purpose
2.21 The bidder / manufacturers shall provide the details of their company setup available in India for
providing after sales service of the equipment supplied by them for the packages. Bidder /
manufacturers shall provide the name, address and contact phone nos., e - mail addresses etc. of the
authorised representative / agency for availing after sales services of the manufacturers of the
2.22 Bidder shall furnish make and models of major equipment of the package namely screw compressor
with driver, electric motors, air dryer, coolers, filters, PLC and control system etc. Bidder shall also
furnish letter of commitment or copy of memorandum of understanding signed with respective sub
vendors, of their participation and association with bidder in the execution of this project and to
provide assistance in installation / commissioning of the packages at each platform. Commissioning
engineers from the respective manufacturer shall be present at platform during the entire period of
commissioning and performance run test of compressor and dryer package.
2.23 Maintenance and operating manuals of the equipment to be provided by the bidder / manufacturers
shall be elaborate and descriptive giving full details on equipment operation & maintenance
requirement, including checklist and schedules for the preventive maintenance of equipment,
equipment part no., part drawings, sequence for assembly and dismantling of parts for maintenance
etc, list and quantity of consumables required for the equipments.
2.24 Bidder shall provide 5 sets of GA drawings, P & ID, in hard and soft copies in a CD, Out of 5 sets two
hard copies of drawings should be laminated, licensed copy of Auto Cad software, equipment data
sheets, electrical equipment data sheets, instrument data sheets.
2.25 Bidder shall quote separately for optional scope of work for providing training of operation and
maintenance staff in two groups for a minimum period of four days each by compressor & dryer
manufacturers separately at respective platform. Equipment manufacturer shall provide certificate to
the trainees at offshore. Bidder / manufacturer shall provide brief / copy of typical training module
offered by them for training along with the bids.
2.26 Bidder is required to submit duly filled in data sheets enclosed in the bid document.
2.27 Bidder shall prepare ‘Bill of Materials’ for the purpose of verifying the items & their quantity by
installation contractor and ONGC.
2.28 Bidder shall submit his bid in hard and soft copy.
2.29 The bidder shall supply the units as per specifications on FOB basis and hand over to the installation
contractor on FOB basis.
3.0 DECK SPACE:
3.1 BPA platform
3.1.1 Combined existing skid size of utility air compressor (2 nos) and dryer is
4700(L)x3785(W)x3500(H) mm. Platform deck shall be extended towards east side as per
enclosed structural drawing to accommodate new separate skids of compressor and air dryer
packages. The total deck space available for installing new packages is
3.2 BPB platform
3.2.1 Separate existing skid size of two air compressors and one air dryer is 3500 x 2200 x 3000 and
3500 x 1450 x 3115. Thus the total deck space occupied by the compressor & dryer skid on
the platform is 3500 x7000x3115. Therefore, total deck space available for locating new
package (2 compressor + 1 dryer) is 7000(L)x3500(W)x3500(H) mm.
3.3 ICW & WIN platforms
3.3.1 The existing deck space mentioned in the bid shall be used and no extra space or deck
extension is permissible.
4.0 OVERHAULING & REPAIR SCHEDULE
Vendor recommended overhaul duration / schedule and spare parts requirement for various types of
overhaul may be submitted along with operation and maintenance manual.
5.0 COMPLETION SCHEDULE:
5.1 Delivery of all the packages shall be completed in 8 months from the date of
LOI. Partial shipment shall be allowed.
Warranty for each package shall be 12 months from the date of commissioning of each package on the platform.
This specification out lines the minimum requirement for design, manufacture,
testing, supply, transportation, hookup, installation and association during installation
commissioning and performance testing of the screw type (oil flooded) utility air
compressors and dryer package at ICW, WIN, BPA and BPB offshore platforms.
The installation and commissioning shall be carried out by a separate contract which
will be awarded separately by ONGC.
The compressor shall be used for meeting the instrument and utility air requirements
of the platform equipment.
2. CODES & STANDARDS:
Applicable codes and standards are listed in appendix 11.
3. EQUIPMENT FURNISHED :
3.1. The vendor shall supply all necessary equipment skid mounted as described herein
after to make a complete and operable unit. The packaged equipment shall include
all but not limited to the following :
Air intake filters and silencers for compressors
Utility air screw (oil filled type) compressors with AC driven induction motor for continuous duty. 415
Volts AC 3 Ph 50 Hz.
Inter-coolers, after – coolers and oil coolers. Coolers should be air cooled with electric motor driven
Oil separators with internal oil removing elements.
Set of Coalescer filters
Moisture separators and drain traps
Air dryer pre filter (duplex Type)
Twin tower split flow externally heated No loss No purge type air dryer with required quantity of
Air dryer after filters (duplex type)
Heater, condenser and KO drum
Dew point analyzer
Inter connecting piping, valves, instrumentation and controls safety devices as described in
specification, P&ID and data sheet (s).
Vendor standard local PLC based control panel (separate for each compressor and dryer units) for
monitoring and fail safe operation of the equipment with minimum attended operation.
Weather proof sound attenuating painted carbon steel metal enclosures designed & constructed for
quick removal and assembly at site with normal skill and tools and tackles.
All necessary items not listed here but required for a complete unattended and safe operation of unit
All above equipments, units and components shall be skid mounted on a common structural
skid, fully assembled, piped, with in let and outlet piping terminated at skid edge with
appropriately rated flanges, wired, tested and painted for marine environment.
4.2 Acceptance criteria : -
As a minimum requirement the offered equipment or the equipment of similar design
Manufactured by the supplier:
- Shall have been tested and
- Shall have been in continuous satisfactory service at off shore for a minimum period of one (1) year.
4.3 Equipment Qualification Criteria(EQC)
4.3.1 Unless otherwise specified elsewhere, the Equipment Qualification Criteria (EQC)
mentioned below shall be applied for acceptance of the offered compressor model.
4.3.2 The vendor for the complete unit (compressor & dryer) shall be an established manufacturer of Rotary-Type
Positive Displacement Compressors. The vendor shall also be the manufacturer of the proposed compressors
having adequate engineering, manufacturing & testing facilities for the same.
4.3.3 The compressor model offered shall be from regular manufacturing range of the manufacturer and shall meet the
following minimum service and manufacturing experience requirements.
Compressors shall be identical in frame designation and type i.e. oil flooded and validly similar in terms of
Frame number, Rotational speed, Inlet and discharge pressures. Inlet temperatures. Actual Inlet flow, Process
Gas, Mechanical Design, Type of Rotor, Rotor Dynamics, Materials, Type of shaft seals etc. as compared to at
least TWO UNITS designed, manufactured. Tested and supplied form the proposed manufacturing plant and at
least ONE of these units shall have successfully operated in the field for at least 8000 hours without any major
problems as on the date of issue of inquiry.
4.3.4 Proven Track Record (PTR)
Compressor vendor shall complete the Experience Record Pro forma as enclosed in the inquiry specifications to
amply prove that the Equipments offered meet the EQC for technical acceptance. Compressor vendor may
furnish additional information to justify that the EQC is being met. In addition, manufacturer’s catalogue and
general reference list for all the above equipments shall also be furnished along with the proposal.
5.0 Design criteria :-
5.1 Conditions of service : -
The equipment shall be designed for outdoor location on an off shore platform with site conditions as
detailed on the attached appendix 1.
The equipment shall be located in an area classification defined in the attached data sheet /
5.2.1 Utilities available are indicated in attached data sheet
5.2.2 The Vendor shall specify the utilities required along with their rate of consumption in his
5.3.1 It is the intent of the Company that the operational hazards be reduced to minimum. Vendor shall use sound
engineering judgment to complete the supply and provide assistance in commissioning that will perform the
required process function without compromising this aim.
5.3.2 All electrical & instrument devices shall meet the requirements for the area classification in which they are
5.3.3 All controls shall operate in a fail safe mode.
5.3.4 All couplings, gears and exposed rotating parts shall be provided with adequate guards of non-sparking
construction. Drive belts if used shall be antistatic type.
5.3.5 Piping shall be arranged in a manner so as to avoid tripping or head room problems.
5.3.6 The requirements of equipment vibrations limits as defined in the ISO 2372 and noise limits as defined in data
In event of conflict between this specification and other documents listed herein the following order of
precedence will govern.
- data sheet(s)
- this specification
- General specification attached as appendices 1-22 in Volume III
- Codes & Standards as per appendix 11
6.0 DESIGN & CONSTRUCTION:
6.1 Compressor :
6.1.1 The compressor shall be oil flooded screw compressor heavy duty industrial type, air cooled type with closed
circuit cooling water if required to meet the specification requirement of compressed air out let temperature.
6.1.2 Industrial mineral oil shall be used for lubrication of the machine. Bidder shall quote for supply of two extra fill
of oil as mandatory spares in the attached list of mandatory spares.
6.1.3 Compressor shall be designed to meet the requirement defined in attached data sheet.
6.1.4 Compressor shall preferably be directly coupled with induction motor. Gear unit when used shall be designed in
accordance with AGMA 420 or an equivalent standard and shall have an AGMA service factor of not less than
2, based on the driver nameplate rating when driver is electric motor. For others drives, gearbox manufacturer
shall recommend it. Bearings shall be forced-feed lubricated unless otherwise specified in data sheet. Necessary
oil cooler shall be provided for cooling of frame lubricating oil.
6.1.5 Coupling and coupling spacer of compressor and driver shall be easily accessible for
replacement in case of failure without disturbing the whole unit.
6.1.6 Each compressor unit shall be complete with air cooled, finned tube type oil cooler, inter & after coolers
(including fan and fan guard), design for 14ºC approach to maximum ambient in accordance with the applicable
standards & codes attached in appendix 11. If located in hazardous area, the fans shall have provision to
suppress sparking consistent with AMCA category B.
6.1.7 Bidder shall furnish P&ID and general arrangement drawing of screw compressor
package along with bids for battery limits details and their scope of supply.
6.1.8 Each compressor unit shall be provided with a dry cartridge type air intake filter / silencer with screens.
Compressor with drives and its accessories, instrumentation and controls shall be enclosed in weather proof
sound attenuating painted carbon steel metal enclosures with single intake and discharge opening suitable for
out door location at offshore. The weather protective and sound attenuating enclosures consists of several easily
removable access doors for inspection and removal of compressor parts, components and motors etc. Noise level
outside the skid shall be as mentioned in compressor data sheet. Enclosures shall be designed and constructed
for quick assembly and removal at site with normal skill, tools and tackles.
Removable section of enclosures shall facilitate handling of compressors parts and
components maintenance by chain pulley blocks.
6.1.9 Oil separator tank at the discharge of compressor shall be designed as per ASME code. This shall be separate
and not integral part or built-in with the compressor casing. Separator tank oil removal efficiency shall be 5 ppm
and compressor vendor shall provide details of internals and specify sizing criteria of the oil separator vessel
and the internals along with type and material of construction of internals provided for the separator along with
6.1.10 Moisture separator with trap shall be provided down stream of inter-cooler and after –cooler for moisture
removal. Compressor vendor shall define moisture separation efficiency along with bids.
6.1.11 Drain trap shall be provided with automatic drain valve and piped to skid drain header for draining of moisture.
A high liquid level switch shall stop the unit should the primary drain ever fail to operate. Design of drainer
shall conform to specification and data sheet of continuous drainer included in the bidding document.
6.1.11 Two stage Coalescing filters shall be provided to reduce the oil content in air to 0.5 ppm in first stage and
further to 0.01 ppm in final phase prior to inlet to air receiver. Bidder shall specify size of filter assembly and
shall provide details for filter cartridges / elements including make, size ( diameter x length ) and number of
cartridges provided and mono-graph for the cartridges separation efficiency pressure drop, operating life cycle
of cartridges and sizing criteria along with bid proposal to check the technical adequacy of the filtration system.
Drainage of oil from coalescers(s) shall be by timer controlled solenoid valve.
6.1.12 Magnetic filler shall be provided in lube oil circuit for collection of magnetic particles.
6.1.13 Material of construction for all filter housings shall be as a minimum stainless Steel 316 series
6.1.14 Suitable anti vibration mountings shall be provided for the compressors, Vibration levels of compressor for the
following operating conditions shall be provided in the bids by manufacturer
Vibration levels during normal operating range
Vibration limits for setting alarm
Vibration levels requiring shutdown of the machine
Vibration levels shall be measured at site by hand held vibration meter with accelerometer at site.
6.1.15 Control system shall be full load/ no load type operating on signals from pressure sensors.
Provision shall be provided in control system such that if idling times
become too long w.r.t full load time the compressor should shut down when the
maximum pressure is attained as per data sheet and comes in to operation when the minimum pressure is
fallen short. In both the cases the idling range is operated at
the minimum for the safety of the machine. The switching frequency should not be
more than three or four times an hour so that main and the electrical devices are
6.1.16 Lube oil temperature shall be maintained for trouble free operation of compressor
through a thermostatically controlled system. Compressor shall shut down at low lube oil temperature to ensure
that there is no condensation of water present in oil takes place during operation.
6.1.17 Compressor shall load or un-load according to the demand as per requirements
Specified in attached data sheet.
6.1.18 Selector switch shall be provided to interchange the normal operating compressor
with stand by compressor or vice versa.
6.1.19 Compressor unit shall be provided with weatherproof sound attenuating painted carbon steel panels, designed
& constructed for quick removal and assembly at
site with normal skill and tackles. Noise level out side enclosures shall be as data sheets
of compressor. Adequate space / access inside enclosures shall be provided for operation
and preventive maintenance of equipments installed in side enclosures.
6.1.20 Lighting shall be provided inside the enclosures as per electrical specification.
Temperature inside enclosures shall not increase more than 5º C over the ambient temperature and to maintain
this inside condition ventilation fans shall be provided to remove the heat dissipated by the equipment.
6.1.21 Observation and inspection windows, hinged access doors shall be provided in
Enclosures for visual observation and routine inspection of equipment and taking
Instruments readings without disturbing the enclosures.
6.2.0 Air Dryer unit :-
6.2.1 Air dryer unit shall be twin tower adsorption type with split flow (no loss no purge type) closed circuit
regeneration with external electric heating and air-cooling. Air dryer vessels, regeneration heater, unit piping
hall be heat insulated. Regeneration shall be by means of heated air as shown on attached P&ID.
6.2.2 The unit shall consist of two identical drying vessels, arranged for automatic change
over such that one tower is always under drying and the other under regeneration.
Visual indication on local panel to indicate the state of each vessel i.e. drying /
Regeneration, shall be provided.
6.2.3 Air dryer unit shall deliver air at the specified dew point. Quantity and pressure as specified on data sheet. Dew
point measurement devices with display (on line) shall be provided to check the dew point of instrument air and
for energy management system.
6.2.4 Duplex type pre-filter for protection against contaminated air and after filter shall
be provided to trap the carryover of desiccant to instrument air receiver shall be provided to meet the filtration
requirements defined in specification.
6.2.5 Control system for the dryer shall be PLC based.
6.2.5 Air dryer unit shall be designed and manufactured to meet the requirement as
defined in attached specification and data sheet.
6.3.0 Vessels :-
6.3.1 All vessels shall be designed, fabricated and tested in accordance with attached General Specification at
appendix 12 and ASME Section VIII Division I.
6.3.2 Corrosion allowance of. 3mm shall be applied for carbon steel parts of vessels, exchangers, separator vessels,
knock out pots and filter housings etc.
6.3.4 ASME Code Stamp shall be provided on all pressure vessels exchangers etc. stated as per General specification
at appendix 12.
6.3.5 The material of construction of vessel and exchanger shall meet the following requirement as a minimum:-
Boiler quality plates for shell, heads etc shall be supplied in normalized Condition
Boiler quality plates over 15mm design thickness shall be ultrasonically examined as per ASTM A – 435.
Material specification :-
Shell, heads reinforcement pads SA-516 Gr. 60
Nozzle SA-106 Gr. B
Nozzle flanges SA-105
Vessels shall be designed for spot radiography as a minimum and dish ends to shell circumferential weld joints as
Pneumatic cylinder and linkages provided for the operation of changes over of four way valves shall be stainless
6.4.0 Skid :-
6.4.1 The skid shall be designed and built to ensure that all equipments stated above
along with all accessories, panel, piping, valves, instrumentation are mounted
suitably and offer maximum flexibility for installation, convenient operation and
maintenance of the unit. The skid shall be designed and built in accordance with
the attached General specification at appendix 9.
6.5.0 Piping :-
6.5.1 Selection, fabrication and installation of piping work shall be as per enclosed General specification at appendix
7, 8 and 13.
6.5.2 Piping shall be arranged adequately supported and connected in such a manner that a minimum number of
fittings must be disconnected to remove the compressor.
Stainless steel flexible connection shall be used where applicable. Accessory items
Including drain trap, pressure regulators, check valves, control and safely devices shall be installed and
connected in such a manner that they can be readily removed.
Replaced or maintained.
6.6.0 Electrical :
6.6.1 All out door equipments shall, as minimum is suitable for hazardous area specified else
where in bidding document and shall be BASEEFA, UL or equivalent international
testing agency for the service and area in which it is to be used.
6.6.2 Electrical equipment and material shall be in accordance with enclosed general specifications at Appendix 2 and
design criteria at appendix 3.
6.6.3 Power supply: 415 V , 50 Hz. Three phase AC available shall be used.
6.7.0 Instrumentation & controls:-
6.7.1 The selection and installation of instrumentation work, as a minimum
shall meet the requirements defined in General specification enclosed at appendix 5 & 6.
6.7.2 Instrument / utility air compressor & dryer package shall have separate self-sufficient PLC based vendor
standard control & monitoring system for each compressor unit and the air dryer unit separately. All shut down
logics interlocks and controls shall be located and performed in these dedicated control systems. Bidder /
Contractor shall be responsible for coordination with Engineer-in-charge at site for proper implementation of
controls. The shut down logics and interlocks shall be designed with fail-safe features as a minimum. All details
shall be finalised during detailed engineering after review and approval of ONGC.
The control system shall have the following features as a minimum:-
- The PLC shall be provided with portable programming unit/ terminal for each package capable of
programming, programme storage and programme modification.
- Auto change over of Lead / Lag of compressor after fixed hours of running to effectively manage running
hours with a facility to change over in manual mode also.
- Vendor / make of PLC shall be chosen from GE Fanuc, Rockwell/ Alan Bradley or Siemens
- Two sets of loaded software in CD’s
- CD read and writes facilities
All necessary monitoring, indication and alarm for compressor and air dryer as well as selector switches and
push buttons shall be available in compressor and dryer control Panel.
The controls & indications that are required to be connected to Company’s remote
platform control panel, shall be terminated in a junction box with terminal strip located at
the edge of skid by the manufacturer and shall be interfaced with platform control panel
in control room by the installation Contractor/bidder
6.7.3 Modular, single front, skid mounted control panel shall control the operation of the package. SS-316 Panel
construction shall be weatherproof NEMA-4 & explosion proof to NEMA-7. The control system and other panel
electronics that are required to facilitate control and operation of compressor and dryer units shall be housed in
a suitable enclosure certified for the specified area classification by a statutory authority.
All signal termination shall be in this panel. Control panel(s) shall be provided with covers/ canopy for protection
from rain in case located out side the enclosures.
6.7.4 Vendor standard control system as a minimum shall include the following warning indication and shut downs
for the unit:-
- Automatic start up and shut down of compressor units
- Automatic parallel operation of two compressors
- Automatic loading and unloading of compressor units on demand
- Compressor air high discharge temperature-Alarm and shut down
- Compressor air high discharge pressure – unload operation
- Oil separator differential pressure high – Alarm & shut down
- Oil separator (air side) discharge temperature high – Alarm and shut down
- Oil cooler discharge temperature high – Alarm and shut down
- Oil separator level high – Alarm and shut down
- Oil pressure low – Alarm and shut down
- Oil level low in sum or oil separator – Alarm & shut down
- Coalescer filter(s) differential pressure high – Alarm and shut down
- Coalescer filter(s) level high – Alarm & shut down
- Oil filter differential pressure high – Alarm and shut down
- Main motor over load – Alarm and shut down
- Fain motor over load – Alarm and shut down
- Blow of pressure high – Alarm and shut down
- Emergency stops – Alarm and shut down
- Re-set /Test
Note :- Control and monitoring of the unit to be read in conjunction with enclosed
Compressor data sheet and P&ID.
- All gauges shall be provided in a separate gauge board only.
As a minimum this shall be as per the standard specification included in the bidding document.
Provision shall be made by the bidder for Status signals for Run, trip and common fault
alarm for compressor and dryer skids separately to be interfaced with platform control
6.7.5 Bidder shall describe the proposed instrumentation and control system along with make/
model and configuration diagram in the proposal / bid for the offered control system.
6.7.6 Front of the panel shall be furnished with the following indicator light as a minimum.
Compressor on Red
Compressor off Green
Compressor Trip Amber
6.7.7. Control panel shall have start & stop push buttons, on & off indication lamps for drive motors of equipment
units and components and provisions for interfacing and interlocking with feeders in switchgear room . Front
of the panel shall also be furnished with following :-
Start & stop from local and stop from remote
Start & stop in manual as well as in auto mode
6.7.8 Alarms & shutdown devices shall be wired through first-out fault indicator. Visual indication for all alarms &
shutdowns and common audible alarm shall be provided in control panel. Packager/vendor shall provide extra
terminals to allow Contractor to connect common remote alarm in central control panel. The remote alarm shall
be provide and wired by the installation contractor.
6.7.9 Instrumentation control panel shall be separate from electrical system control panel in the skid.
6.7.10 All electronics instruments shall be designed for immunity from EM & RF interferences as per IEC-801.
6.7.11 Method of protection to be followed in general for electronic instruments shall be as per the requirements given
Switches & solenoid valves Explosion proof & weather proof
Transmitters, transducer & Intrinsically safe & weatherproof
All field mounted electronic instruments (transmitters, switches, solenoid Valves ) & junction boxes shall be
explosion proof and weather ‘or’ intrinsically safe and weather proof certified by recognized authorities like FM
/ BASEEFA / CENELEC /CMRI etc for electrical classification NEC class – 1 Division –1 , Group – D as a
minimum. Intrinsic safety approval shall be based on entity concepts and the Contractor shall carry out
necessary compatibility checks before selecting the instruments, cables and barriers.
6.7.12 Power for Instrumentation & control shall be supplied from platform power system at a single point, all further
distribution shall be in bidder / contractor scope, platform power system is all follows :-
- 24V DC +5% negative earthed for all instruments controls & interlock system.
- 220V AC 50 Hz (Non ups ) for level gauge illumination if required.
Bidder / Contractor shall indicate estimated power consumption for start up & normal operation of instruments
and controls along with bids.
6.7.13 Material of construction of instruments, instrument fittings, valves and other related accessories shall be SS-316.
Non – stainless steel exposed surfaces shall be painted as per General Specifications at appendix -4.
6.7.14 Make / selection of instrument vendor & instruments shall be subject to Company’s approval. Bidder shall
furnish proposed sub vendors list of instruments along with bids. Suggested vendor list for instruments may be
provided by the company.
6.7.15 All instruments shall be suitable for use in a humid and tropical offshore climate. All necessary weather and anti
corrosion protection to instruments shall be provided to prevent damage from saline and corrosive process
atmosphere. All field instruments shall be enclosed in suitable weatherproof NEMA-4X enclosures as minimum
to protect them from site conditions specified in General Specifications at appendix 1. Plastic bags shall be
provided with all field instruments to protect them during handling installation and commissioning.
6.7.16 Bidder / Contractor’s scope of supply shall include all new instruments and control items as per this
specification including all cables, FRP cable / tube trays, trays supports, tubes, junction boxes & cable glands &
other material as required for the implementation of the above work within skid battery limits.
6.7.17 Bidder shall furnish list of drawings & documents to be prepared by him and submitted for Company’s review
and approval. Instrument specification & data sheet shall be prepared by the bidder / contractor as per typical
data sheets attached with specification & submitted for Company’s review and approval. Wherever typical data
sheet(S) not available for any instrument bidder/ contractor to prepare as per ISA S.20
The typical instruments data sheets included in this bid package and pertaining to the scope as per this bid
package requirement and attached P&ID’s are for establishing a minimum level of quality and service
requirements and shall be followed by the bidder/ contractor while making his own data sheet (s). These
specifications do not include any detail for the instrumentation required to be supplied by the bidder/ contractor.
Contractor shall be responsible for the complete design, installation and workability of instruments and control
All electronic transmitters shall be microprocessor based non-retro-fit smart type with an accuracy of 0.075 of
span over a rangability of 110
Only transmitters (no switches) with indicators and separate transmitters for alarm & shut down shall be
provided. Transmitters shall be selected from make like Rose mount, Yokogawa, ITT, Fuji and hand held
terminal to be provided for calibration should be make specific.
7.0 Protective coating:
Carbon steel surfaces, piping, vessel fittings, supports and structural skids shall be coated in accordance with attached
General specification attached at appendix 4
8.0 Inspection & Testing:
8.1.0 Vendor shall carry out various tests as per attached equipment data sheet and applicable codes & standards.
Test certificates shall be submitted for Company’s approval.
8.2.0 Company or it authorized representative or certifying agency shall have access to inspect the equipment at any
stage during manufacture. During inspection, material test certificates, shop test data, certificates for bought out
components and other relevant information shall be furnished as to ascertain that the specifications and quality
are complied with.
8.3.0 Vendor shall furnish for company’s approval detailed description of test procedure(s) at least two (2) months
prior to scheduled shipment. The following tests shall be performed as a minimum.
8.3.1 Equipment shall be performance tested as per enclosed equipment data sheet(s) and
specifications in shop. Tests specified as “Witnessed” in data sheets shall be carried out in presence of third
party inspection agency.
8.3.2 Vessels, piping and the system as a whole shall be hydro statically tested as per the applicable codes in shop.
Test pressures shall be in accordance with the maximum working pressure of individual systems.
8.3.3 Functional test(s) of control system shall be performed in shop. Functional test shall be carried out in presence
of third party inspection agency.
8.4.0 Performance test of the compressor and dryer package(s) shall be carried out individually at offshore locations
by another Bidder/Contractor on completion of installation and commissioning work for establishing
performance/output of the unit as per specification. Bidder shall arrange to co ordinate with offshore installation
contractor for all necessary personnel, tools, tackles equipments, spares chemical lubricants etc. as required by
him for start up, commissioning and 72 hours uninterrupted performance run test of the package. Any assistance
required during performance testing at platforms shall be provided by the installation contractor in terms of
manpower, general tools & tackles only. Special tools, instruments, chemicals etc. shall be arranged by the
8.5.0 Q A Plan approved by the third party inspection agency shall be submitted to ONGC for final approval.
9.0 Warranty :
Vendor shall have the final & total responsibility for the design and performance of all equipments supplied under this
specification. Vendor shall warrant the equipment furnished by him and the performance of the said equipment in
accordance with this specification and attached appendices. The warranty shall be package wise and shall start from the
date of commissioning of each package at offshore platform.
10.1 Vendor shall recommend and provide spare parts needed for start up and commissioning. In addition Vendor shall
also furnish separate itemized priced list of recommended spare for one (1) year’s normal operation and
maintenance, valid for supply for a period of 2 years after successful commissioning. Recommended spares shall
take in to account related factors of equipment reliability, effect of equipment downtime upon production or safety,
costs of parts and availability of equipment service facilities. List shall include the requisite quantity of chemical
required for the package during one year of normal operation.
10.2 Bidder shall supply two years consumable operation spares as mandatory spares for total package as per attached
list at appendix 17.
10.6Spare parts furnished by the vendor shall be wrapped and packaged so that they will be preserved in original as new
condition under the normal conditions of storage as anticipated in India and shall be properly tagged and coded so
that later identification as to intended equipment usage will be facilitated. They shall be packaged separately,
clearly marked as “Spare Parts” and shipped at the same time as the equipment Packing lists shall be furnished so
that the parts can be handled without un crating if desired. Start up spares shall packed and identified separately.
Vendor shall provide two sets of special tools required for erection, operation and maintenance of the furnished
12.0 Packing & Transport:-
The offered equipment along with their accessories shall be shipped packed in wooden crate. They shall be wrapped
with polythene sheets before being placed in crates to prevent damage to finish. Crates shall have skid bottom for
13.0 Vendor Data Requirement:-
13.1 With proposal:-
Equipment specifications, catalogues, data sheets, deviation schedule and other relevant data as per attached “Vendor
Data Requirement” sheet to facilitate the Company in evaluating the equipment selection.
13.2 After order placement:-
Drawings and data to be furnished by the Bidder/Contractor for Company’s review/approval as outlined in the
attached Vendor Data Requirement sheet shall be submitted as a part of Equipment Data Book.
STANDARD SPECIFICATION FOR INSTRUMENT AIR DRYER UNIT
2.0 CODES AND STANDARDS
3.0 TECHNICAL REQUIREMENT
4.0 INSPECTION AND TESTING
5.0 PROTECTION AND TESTING
6.0 PCKAGING AND IDENTIFICATION
7.0 SPARE PARTS
This specification. Outlines the minimum requirements under which the manufacturer shall design,
manufacture, test and supply the Instrument Air Dryer Unit complete with all accessories. This
specification also lays down the requirements for control and instruments, electrical and associated pipe
2.0 CODES AND STANDARDS
2.1 The latest edition of following codes, and standards shall govern:
Pressure Vessels - ASME Sec.VIII Div.I
- ASME Sec.IX
Heat Exchangers - TEMA ‘C’ and
ASME Sec.VIII Div,I
Piping - ANSI-B 31.3
Pressure relieving system - API-RP-520 PART I/II
Material specification - ASME EC.II & ASTM
Pipe Flange & Fittings - ANSI – B 16.5
- ANSI – B 16.11
- ANSI B 36.10
3.0 TECHNICAL REUIREMENTS
3.1 Type of Unit – Air dryer unit
The drying process shall be externally heated No loss purge type only
3.2 Operation and Control
3.2.1 The unit shall be fully automatic in operation, with a provision for manual operation in case of timer failure.
3.2.2 All equipment of the package unit shall be hooked up in close circuit with interconnecting pipe work and
interlocked in proper sequence of operation for safety.
3.2.3 Following interlocks/alarms indication shall be provided on the skid as a minimum, as applicable for the system.
a) Interlock system to ensure that regeneration system is initiated only when the four way valves are switched
on in correct position.
b) Very low flow in the regeneration circuit to trip the heater.
c) Audio-visual indication to indicate excessive regeneration air temperature
d) Audio-visual indication to indicate failure to switch over of four way valves.
e) Audio-visual indication to indicate low flow in regeneration circuit..
f) Indicating lamps for control panel on, absorber under absorption, regeneration or cooling, heater on, timer
g) Audio visual alarm to indicate high air temperature after regeneration cooler
h) Audio visual alarm to indicate blower motor failure (for blower type only)
i) Interlock between heater and blower shall be provided so that the heater will not start till the blower is
3.3.1 Each adsorber shall be equipped with a suitable corrosion resistant austenitic stainless steel screen for desiccant
support. Screen shall be in suitable sections so as to facilitate replacement through manhole. Provision shall be
made for replacing and removing desiccant without dismantling the connected pipe work.
3.4.1 Heating of re-generation air, wherever applicable shall be by means of Electric Heater. Heater shall have at
least 20% excess capacity.
3.4.2 The heater may be of internal type, provided on each adsorber for purge type of dryers. For other type of dryers
the heater shall be external type. The electric heating elements shall be U-Type and made from Ni-chrome steel,
or incolloy material.
3.4.3 The heater shall have 2/3 number of banks depending on the heater capacity.
3.4.4 Safety valve shall be provided, for external type heater.
3.4.5 Suitable arrangement shall be provided to control regeneration air temperature.
3.5 Shell & Tube Heat Exchanger (regeneration cooler)
3.5.1 The heat exchanger shall be horizontal type with carbon steel saddle supports.
3.5.2 Regeneration cooler shall have 20% margin on surface area.
3.5.3 The heat exchanger shall have SA 179 (Carbon steel) cold drawn tubes. The standard type size shall be 20mm
O.D. and tube pitch shall be 25mm. Minimum tube thickness shall be 14 BWG. The tube shall be seamless
Expanded tube to tube sheet joints shall be provided. U tubes, shall not be used/
3.5.4 Heat exchanger shall be designed and located such that they can be removed or services without disturbing pipe
3.5.5 Minimum 20 NB vent shall be provided at the highest point and drain shall be provided at the lowest point on
the shell. Safety valve discharge shall be located at the highest point.
3.5.6 Bolting for channel and girth flanges shall consist of continuously threaded studs conforming to SA 193-B7
with nuts in accordance with SA 194-2H.
3.5.7 The tube side velocity for cooling water shall be in the range of 1.25 to 2.5m/s at mean temperature.
3.5.8 Fouling factor for air side and cooling water side shall be considered as 0.0004 hr m’C/keal (each side) unless
3.6 Pre filter and After filters
3.6.1 A pre filter with isolation and by-pass arrangement shall be provided at the inlet. Pre filter shall be fitted with an
automatic drain trap with by-pass arrangement.
3.6.2 The pre filter shall be able to remove water and oil droplets and dust down to 1 microns particle size with an
efficiency of 99%.
3.6.3 Two numbers after filters-one in operation and one as stand-by shall be provided at the dry air outlet for
arresting the desiccant dust particles. The after filter shall be valved to permit each item to be services during
normal operation. The after filters shall have 99% efficiency for 5 microns particle size.
3.6.4 The cartridges shall be of PECO/PALL/BEA
3.7 Moisture Separator
3.7.1 Moisture separator with automatic drain trap and by pass arrangement shall be provided after the regeneration
cooler. A demister shall be provided in the separator outlet.
3.8 Blower (For Blower Type Only)
3.8.1 Blower shall be complete with drive electric motor, common base frame with foundation bolts, flexible
connection, V-belt or flexible coupling and V-belt/coupling guard, damper at outlet etc. Fan casing should
have drain plug, inspection door and lifting lug. Noise level shall not exceed 85 dBA at I metre from the fan,.
3.8.2 The rotor assembly shall be statically and dynamically balanced.
3.8.3 Drive motor sizing should have 20% margin in case of V-belt driven fan or 10% margin in case of direct driven
fan over max shaft power during operation or under cold start condition.
3.8.4 Blower/fan shall be heavy duty type with ample wearing and bearing surface for continuous operation without
excessive vibration. It shall have at least 10% margin on capacity and head. A minimum service factor of 1.6
shall be used for selection of belts.
3.9 Pressure vessels
(Absorber, Heater, Regeneration cooler, moisture separator and receiver)
3.9.1 All the pressure vessels shall be designed, fabricated, inspected and tested as per
ASME SEC. VIII DIV. I with latest addenda.
3.9.2 The wall thickness of Vessel shell and heads shall be calculated with design pressure and temperature in
accordance with applicable codes. In no case the thickness (in mm) be less than following:
For diameter less than 2400 mm
Wall thickness = D/1000 + 1.5 + corrosion allowance.
For diameters 2400 mm above.
Wall thickness = D/1000 + 2.5 + corrosion allowance.
D = Diameter of vessel in mm.
3.9.3 Minimum corrosion allowance for carbon steel shall be 3.0 mm, unless otherwise
3.9.4 Following guide lines shall be followed for selection of carbon steel material for pressure parts
From 0º C to + 425º C – SA 516
From 0º C to + 425º C – SA 105 tested & inspected.
c) Nozzle pipes
From 0º C to + 425º C – SA 106.
Elbows shall be long radius type.
From 0º C to + 425º C – SA 193 GR B7, SA 194 GR 2 H.
All internal bolting shall be stainless steel type 304.
1.5 mm thick compressed asbestos gasket upto 457 mm diameter, 150 lbs RF rating 3 mm thick for
sizes over 457 mm.
Compressed asbestos 1.5 mm thick gasket shall be used for internal assemblies.
3.9.5 Following guidelines shall be followed for selection of carbon steel material for non pressure parts
From 0º C to + 350º C
SA 53, IS 1239
3.9.6 Specification of carbon steel plates
Carbon steel plates used for this job shall conform to latest issue of specifications SA -20 with additional
requirements mentioned herein.
a) One product analysis of each heat shall be carried out & reported chemical analysis shall be as per
applicable specifications with carbon content not exceeding 0.23%.
b) Normalised plates with workman like finish shall be used. No reconditioning / repair shall be
c) Plates of thickness from15 mm to 50 mm shall be examined ultrasonically as per SA – 435.
3.9.7 Manholes/Hand holes and Nozzles
a) All nozzles, above 3” NB size shall be provided with reinforcement pads. Calculations for reinforcement
pads as per ASME shall be submitted.
b) Small vessels shall be provided with two pad type inspection opening of 150 NB size.
c) For vessels with diameter less than 900 mm and having removable internals, shell flanges shall be provided.
d) For vessel with diameter 900 mm and above, man hole of 450 NB shall be provided. Manhole cover shall
be provided with davit
Dished ends shall be of seamless construction, torispherical or 2:1 ellipsoidal type and shall be heat treated after
forming as per as per ASME SEC –VIII Div.1. However in case hot forming is carried out inside the
normalizing range, no stress relieving is necessary.
a) All flanges shall be as per ANSI B-16.5. Larger flanges not covered by ANSI-B-16.5 shall be to MSS-SP-
b) For nozzles 100 NB and below only weld neck flanges shall be used slip on flanges may be used for nozzles
above 100 NB, 150 lbs rating.
c) All Flanges above 150 Lbs rating shall be weld neck type.
Welding of all components shall be of a high order as a minimum requirement, welding process, heat treatment
details and non destructive quality control testing etc. for piping shall meet the requirements of the welding
specification charts (Sht. 14 of 4). Pressure parts joined by “but” welds shall be full penetration. Where both
side welding is not accessible, root run by tungsten inert gas process or backing strip may be used to ensure full
penetration. Backing strip, if used, is to be removed after welding.
3.9.11 Post Weld Heat Treatment
Vessel shall be heat treated whenever it is required due to service requirement or
due to code requirements. Vessels shall be post weld heat treated as a complete
unit and no welding is permitted once post weld heat treatment is done.
A minimum of 10% of the main seam welds and 100% of all ‘T’ junctions shall be radiographed.
Defective welding disclosed by radiography shall be chipped out, reviewed and re-
radio graphed. Moreover, any other additional radiographs or test required by
applicable design/construction code are to be carried out. All fillet welds should be
a) Vessel weighing more than 5.0 MT shall be provided with lifting lugs.
b) Fabrication tolerances indicated in EIL standard 7-12-001 shall be adhered.
c) Manufacturer shall furnish additional tow sets of gaskets for every manhole and nozzles provided with
blind flanges. The final gaskets shall not be used for conducting tests in shop.
d) Nozzles up to 50 NB size shall be stiffened with 2 Nos. stiffeners of 40 mm wide x 6 mm thick flats welded
e) Vessel diameter 300 NB & below shall be made from seamless pipe only
f) Rolling of plates for making shell shall be lengthwise.
Piping within the battery limit shall be carried out as per ANSI B 31.3 and good engineering practice. Piping
materials shall be as per EIL standards s[e/ Mo. 6-44-05 A3A & J3A class)
The horizontal clearance in front channel or bonnet flange shall be bundle length + 1 meter.
Access platform with ladder for desiccant filling on adsorbers shall be provided as required.
Instrumentation shall be as per General specifications in Appendices 5 & 6
3.12 Electrical Equipment Specifications
3.12.2 Heating Element
188.8.131.52 Electric Heater shall comprise of required numbers of elements of same KW rating spare capacity as per Cl.
No. 3.4.1 shall be provided.
184.108.40.206 The heater’s surface shall be coated with suitable rust resistant point.
220.127.116.11 Skin temperature thermocouple at suitable locations shall be provided if specified elsewhere, to cut off the
power supply to heating elements where the set temperature is exceeded/
18.104.22.168 Terminals of individual heater elements shall be brought out to a IP-55 terminal box mounted on the unit and
with the help of Heat Resistant wires/copper bus, bars the start point/bank formation shall be done in the
22.214.171.124 Two nos. of each studs shall be provided on terminal box for connection to purchaser’s earth grid.
3.12.3 Heater control panel
126.96.36.199 Heater control panel shall be in line with Appendix 14.
188.8.131.52 Heater control panel shall comprise of TPN incoming switch fuse and contactor. All hardware required to
switch the heater in various combination/groups shall be provided. It shall be possible to isolate different
groups individually. DOL starter feeder for blower motor shall also be included in the control panel.
184.108.40.206 Control supply shall be 230 V AC tapped between phase and neutral.
220.127.116.11 If heater control is Thyristor type then its design & supply should be as per Appendix 18.
3.13 Thermal Insulation
The following materials with the corresponding weather protection cladding as specified herein shall be used
for all piping/ equipment/vessels etc.
Material specification Resin Bonded Mineral Wool
Performed pipe insulation as per IS 9842
Metal-mesh covered bonded mineral fibre blanket & blanket type pipe insulation as per IS 8183.
Density Pipe sections density 140 kg/m³ for piping and
Mattress (lightly resin bonded) density min. 120
kg/m³ for others.(Above 14’ including pipes
Aluminium cladding 26 SWG up to 14’ for preformed pipe sections 24
SWG above 14” for lightly resin bonded mineral
wool for pipes, vessels, eqpts. Etc.
Minimum thickness of insulation shall be as follows:
4.0 INSPECTION AND TESTING
4.1 Equipment shall be subjected to stage wise expediting, inspection and testing at vendor’s/sub vendor’s works by
purchaser/its authorized inspection agency. Vendor shall submit Quality Assurance (QA) procedures before
commencement of fabrication.
Approved QA procedures shall form the basis for equipment inspection.
4.2.1 Fittings, valves, instruments, other accessories like filters etc. shall be duly tested and manufacturer’s test
certificate shall be furnished.
4.2.2 All the pressure vessels shall be hydrostatically tested and inspected as per applicable codes and standards. The
total skid shall be hydro tested or pneumatically tested at applicable pressure. Any other tests as per data sheets,
standards, codes shall also be performed.
4.2.3 Any or all the tests, at purchaser’s option, shall be witnessed by purchaser/its authorized inspection agency.
However, such inspection shall be regarded as check up and in no way absolve the vendor of his responsibility.
4.3 Performance Testing and Guarantees:
4.4.1 The unit shall be performance tested at site after commissioning. The guaranteed parameters shall be checked
during the performance test. All instruments necessary for performance testing shall be arranged by the vendor
at side. Calibration of all testing equipments shall be done by vendor.
4.4.2 Vendor shall guarantee the following:
- Capacity of the unit.
- Dew point of air at the outlet through out the cycle including the cycle
Change over period.
- Pressure drop across the unit.
- Utility consumptions
5.0 PROTECTION AND PAINTING
5.1 All exposed carbon steel parts to be painted shall be thoroughly cleaned from
inside and outside to remove scale, rust, dirt and other foreign materials by
wire brushing and said blasting as applicable Minimum acceptable standard in
case of power tool cleaning shall be St.3 and in case of blast cleaning shall be Sa 2
1/12 as per Swedish standard SIS 0055900.
5.2 Non-ferrous materials, austenitic stainless steels, plastic or plastic coated
materials insulated surfaces of equipment and pre painted items shall not be
5.3 Stainless steel surfaces both inside and outside shall be pickled and passivated
5.4 Machines and bearing surfaces shall be protected with varnish or thick coat of grease.
5.5 Depending on the environment, following primer and finish coats shall be applied.
i) Normal industrial Primer : 2 coats of Red oxide zinc chromate
25 microns )min.) thick each
Finish coat : 2 coats of synthetic enamel, each 25
Microns (min) thick.
ii) Corrosive Primer : 2 Coats of Epoxy zinc chromate
industrial each 35 microns (min) thick.
iii) Coastal and Primer : 2 coats of high build Chlorinated
marine Rubber zinc phosphate, each 50
microns (min.) thick
iv) All environments Finish : 2 coats of heat resistant
Aluminium paint suitable for
specified temp. each 20 micron
(All values refer to dry film thickness)
5.6 The colour of finish coat shall be intimated to vendor after placement of order
6.0 PACKAGING AND IDENTIFICATION
6.1 All packaging shall be done in such a manner as to reduce the volume. The
equipment shall be dismantled into major components suitable for shipment and
shall be properly match marked for site erection.
6.2 Attachment, spare parts of the equipment and small items shall be packed separately in wooden cases. Each item
shall be appropriately tagged with identification of main equipment, its denomination and reference number of
the respective assembly drawing.
6.3 Detailed packing list in water proof envelope shall be inserted in the package
together with equipment.
6.4 Each equipment shall have an identification plate giving salient equipment data,
make, year of manufacture, equipment number, name of manufacturer etc.
7.0 SPARE PARTS
7.1 Vendor shall submit his recommended list of spare parts with recommended
quantities and itemized prices for first two years of operation of the equipment.
Proper coding and referencing of spare parts shall be done so that later
identification with appropriate equipment will be facilitated.
7.2 Recommended spares and their quantities should take into account relate
factors of equipment reliability, effect of equipment down time upon production or
safety, cost of parts and availability of vendor’s service facilities around proposed
location of equipment.
7.3 Vendor shall also submit a list of recommended commissioning spares with
quantities and the itemized prices.
SAMPLE DATA SHEETS of COMPRESSOR,
AIR DRYER & ELECTRIC MOTOR
DATA SHEET FOR I/U AIR COMPRESSOR
1. Location : Platform
2. Tag No.s : C- & C-
3. Nos. required : 2 Nos., 1 No. working,1No. standby
4. Service : Utility Air
5. Site : Offshore, outdoor
6. Drive : Direct couple
7. Duty : Continuous
8. Service : ----
9. Type : Flooded screw with separator
10. Gas handled : Air
11. NM3/hr. : 800
(1.033Kg/cm2 A, 0C dry)
12. Pressure (kg/cm2 A) : Normal atmospheric rated – 1.033
13. Temperature (Degree C)
Min./Max. : 15/43
14. Relative humidity (%) @35C : 80
15.Molecular weight(M) : 29
16. Pressure (Kg/CM2 g) : 11.5 min.
17. Temperature(Degree C) : 55.0
18. Signal source type : Electronic
19. Noise specification : Applicable to machine, applicable to
neighbourhood, acoustic housing required
20. Sound level : 88 dBA @ 1.0m
21. Painting : As per General Specifications in Appendix 4
22. Unusual conditions : Saliferrous
23. Bearings Number : Male rotor DE
Female rotor DE
24Rotation viewed from compressor driven end : CW
1. Bidder to submit completely filled in data sheet along with bid to check the technical adequacy of the offer
2. Air fin cooler shall be sized/thermal designed with ambient temperature of 40C
3. Both compressors shall shut down when the system pressure is 11.5 Kg/cm2g.
4. System pressure and set pressure requirement shall be harmonized w.r.t. the discharge pressure/set pressure of
other Compressors of IC complex during post order stage.
5. Fastening of the compressor blocks, covers etc. shall be with stainless steel hexagonal headed bolts and nuts
only. Use of Allen bolts or hex socket head bolts is not permitted.
6. Bidder to specify compressibility, inlet volume (NM3/hr) (wet/dry) at inlet and discharge conditions.
7. Bidder to specify performance parameter – BKW required (all losses included), speed (RPM) pressure ratio ®,
volumetric efficiency (%), silencer differential Pr. kg/cm,
8. Bidder to specify speeds – max. cont. max. (tip speeds, m/s @ max. operating speed, min. allowable speed,
vibration – allowable levels peak to peak.
9. Bidder to specify shaft material, casing material and type, cladding material, the type of shaft seals, bearings,
housing construction, type of material, max. working pressure, max. design pressure, rotor – material no. of
10. Bidder to specify coupling – make, model, lubrication, type.
Vibration detectors – type, couple, number at each shaft bearing, total number manufactured. Base plate shall
have drip rim.
11. Bidder to specify lube oil system, weight of compressor skid and recommended crane capacity.
DATA SHEET FOR MEDIUM VOLTAGE SQUIRREL CAGE INDUCTION MOTOR
ELECTRICAL DESIGN DATA - PLATFORM
Description Specifications Bidder’s offer
Motor tag No.
1. Voltage 415 ± 6 %
2. Frequency (Hz) 50 Hz ± 3 %
3. Fault level (KA) 50 KA for 1 sec. for the
4. Duty Continuous
5. Phase 3
6. Connection Delta
7. No. of terminals 6
8. Design Ambient temperature 40 °C
9. Temp. rise 80 °C
10. Cable size (mm²) Later
11. Type of cable PVC sheathed Cu
12. Enclosure type IP – 55 WP
13. Cooling TEFC
14. Insulation class ‘F’ with temperature rise
limited to that of ‘B’
15. Applicable standard GS in Appendix 3
16. Hazardous area classification/Gas group Zone-2, Gas group-
class – T3
17. Type of explosion protection Ex(n) / Ex(e) / Ex d for motors located within compressor enclosure.
Ex(d) Ex d / Ex e / Ex n for motors located out door
Technical particulars from Driven Equipment manufacturer
18. Suggested Motor rating in KW / Manufacturer *
19. Shaft Kw / Kw at end of curve *
20. Speed / rotation of equipment from coupling end *
21. Starting / max torque required (mKg) *
22. Equipment / coupling type *
23. Starting condition – On no load / Under loaded *
Technical Particulars from Motor manufacturer
24. Manufacturer *
25. KW rating *
26. No. of poles *
27. Frame designation *
28. Mounting *
29. Full load speed (rpm) *
30. Full load torque (mkg) *
31. Starting torque as % of full load torque *
32. Full load current (A) *
33. Starting current at 100 % Voltage (A) *
34. Breakdown or pull out torque % *
35. Rotation viewed from coupling end *
36. Starting time at 80 % V (Sec.) *
37. Starting time at 100 %V (Sec.) *
38. Power factor at 100 % load *
39. Power factor at 75 % load *
40. Efficiency at 100 % load *
41. Efficiency at 75 % load *
42. Space heater watts /volts ( for motors rated 3.7 *
Kw & above /240V, 1 Ph., 50 Hz.)
43. Bearing type /No. DE *
44. Bearing type /No. NDE *
45. Type of lubrication *
46. Weight of motor (Kg) *
47. Canopy required / not required *
1. Data marked with ‘*’ shall be furnished along with the offer for bid evaluation.
2. Separate datasheet shall be submitted for each of the motors of the package.
DATA SHEET - AIR DRYER
Project : Platform
No of units : One
Service : To dry air delivered by Air
Compressor. Suitable for instrument duty
Type : Split flow desiccant type
OPERATING CONDITION AND DATA
Capacity of unit (outlet), Nm3/hr : 640
Source of air supply From air compressor through pre filters.
Pressure, Kg/cm²g As per compressor data sheet
Temperature ºC 30 to 54ºC
Condition Saturated with water
Oil content 0.01 ppm (to) be confirmed by compressor
Pressure, Kg/Cm²g 11. 0
Temperature, ºC 55.0 Max
Condition Dew point (-) 40º C at atmospheric pressure
Type :Desiccant type (Activated Alumina) :
Split Flow, closed circuit system with
electrical Heating and air cooling for heated no purge type
Pressure, Kg.cm²g 12.5
Temperature ºC 250
Operating Cycle 4 hours drying &
4 hours regeneration plus cooling
Max. Pressure drop Kg/cm2 0.5
Inlet /Outlet air connection 80 NB
Turn Down 40%, without adjustment in control logic
Controls Automatic with manual overrides
Dew-Point Analyser Yes, installed with alarm at Local and main
Insulation Air dryer vessels, Regeneration Heaters and
Associated piping shall be heat insulated
Electric Power 415V ±6%, 3 Phase, 50 Hz +3%
220V ± 6%, Phase, 50 Hz + 3%
24 V DC
Direction of Air flow
Adsorption Top to bottom
Heating Bottom to Top
Cooling Bottom to Top
Type Activated alumina
% dynamic adsorption capacity in the (Company to approve )
Design Code ASME SEC.VIII DIV. I (Latest Edition)
Corrosion allowance 3 mm
Material of heating element Chrome Nickel
HEATER CONTROL PANEL
Input power supply 415 v + 5%, 50 Hz + 3 %, TPN AC
Design Code ASME SEC VIII DIV.I (latest Edition )
Corrosion allowance 3mm (minimum)
Continuous drainer Provided
PRE FILTER AND AFTER –FILTER
Filter Cartridge PRE-FILTER AFTER-FILTER
Solids in feed Water & oil droplets Desiccant dust
Housing Design code ASME SEC. VIII, DIV.I (Latest Edition)
Corrosion allowance 3 mm (min) 3 mm (min)
Direction of flow
Elements cleanable Yes/No
Cleaning procedure (Give detailed write up.)
Holding and sealing Arrangement As per cartridge manufacturers standard/