VIEWS: 16 PAGES: 11 POSTED ON: 9/12/2012
June 26, 2009 SUMMARY OF REQUIREMENTS The following is a brief summary of the new and revised paragraphs in the Standard for Flow Control Valves For Anhydrous Ammonia And LP-Gas, UL 125, which have a future Effective Date of June 10, 2011 and the action that may be required to determine compliance. Para/ New or Revised Wording Impact Comment Sections New title is more descriptive of the type of valves covered. New No Edition was issued Title Flow Control Valves for Anhydrous Ammonia and LP-Gas Impact because of major additions to address the many types of valves covered. These requirements cover the following types of anhydrous ammonia and liquefied petroleum gas (LP- Gas) valves that are used to control the flow of liquid Editorial to better reflect and/or vapor into and out of containers, or in piping No 1.1 the application for these systems between containers, or between containers and Impact valves utilization equipment, and are for use at temperatures within the range of minus 40°F (minus 40°C) to 130°F (55°C) a) Shut-off Valves (primary or secondary, and manual or automatic), b) Excess Flow Valves, c) Back Pressure Check Valves, d) Filler Valves, The standard has been e) Vapor Return Valves, and expanded to document No 1.1 a-j f) Actuated Liquid Withdrawal Excess- historical requirements for Impact Flow Valves; LP-Gas and NH3 valves g) Multiple function valves; used for flow control. h) Internal valve; i) Emergency shutoff valve; and j) Lever operated transfer valve. These requirements do not cover shut-off valves of the type commonly referred to as "cylinder valves" used on This standard does not containers constructed under Department of No cover cylinder valves but 1.3 Transportation (DOT) Specifications. Requirements for Impact references UL1769 for these valves are contained in the Standard for Cylinder such requirements. Valves, UL 1769. This standard does not cover relief valves but These requirements do not cover safety relief valves. references UL132 for Requirements for these valves are contained in the No 1.4 such requirements. Standard for Safety Relief Valves for Anhydrous Impact Ammonia and LP Gas, UL 132. Subject: 125 Page 2 of 11 June 26, 2009 Para/ New or Revised Wording Impact Comment Sections These requirements do not cover automatic shutoff valves Excludes electrically that use electricity to actuate the valve member. No 1.5 operated valves. Those Requirements for these valves are contained in the Impact valves covered by UL429. Standard for Electrically Operated Valves, UL 429. 1.8 Except for such observations as are required to ascertain Editorial – clarifies that performance characteristics, the assigning of pressure No excess flow valves do and/or flow capacity ratings, other than for excess flow Impact have a flow capacity valves, is not within the scope of these requirements. rating. A product that contains features, characteristics, components, materials, or systems new or different from those covered by the requirements in this standard, and that involves a risk of fire or of electric shock or injury to persons shall be evaluated using appropriate additional UL requirements are not component and end-product requirements to maintain the intended to address level of safety as originally anticipated by the intent of this No issues specific to the 1.9 standard. A product whose features, characteristics, impact certification of a product, components, materials, or systems conflict with specific therefore this paragraph requirements or provisions of this standard does not is being deleted. comply with this standard. Revision of requirements shall be proposed and adopted in conformance with the methods employed for development, revision, and implementation of this standard. The service pressure rating of a valve intended for use in anhydrous ammonia and/or LP-Gas service shall not be No change in intent. No 2.1 less than 250 pounds per square inch (psi) (1.7 MPa) and Separating out LP-Gas impact shall not exceed 1/5 of its rupture hydrostatic strength test from NH3 valves. pressure. The service pressure rating of a valve intended for use in LP-Gas service shall not exceed 1/5 of its hydrostatic strength test pressure and shall be in accordance with Table 2.1. (NEW) Table 2.1 Three pressure ratings Service pressure rating of LP-Gas valves will now be allowed for valves for LP-Gas as Service Minimum pressure rating No 2.2 LP-Gas vapor at operating indicated by new table impact pressure of 125 psi (0.9 MPa) 125 psi (0.9 MPa) gauge 2.1, but this will not gauge or less impact currently Listed LP-Gas liquid, or vapor at valves. operating pressure over 125 250 psi (1.7 MPa) gauge psi (0.9 MPa) gauge and at or below container pressure Higher than container 350 psi (2.4 MPa) gauge, or the pressure MAWP, whichever is higher Glossary. A new glossary section has been included in 8 th Definitions consistent Section No Edition to define the valves covered by the standard. (The with previous and current 4 impact th entire glossary has not been included. See 8 Edition) requirements. Moved requirement to a An internal type valve, for which the mating flange is No new Section devoted to 5.3 provided as part of the container in which the valve is to impact internal valves – No be installed is not required to comply with 4.2. change in requirements Two or more subassemblies intended to be assembled in the field as a unit shall be capable of being joined together No Clarified historical 5.7 without requiring any of the subassemblies to be cut, impact requirement. drilled, or welded. Subject: 125 Page 3 of 11 June 26, 2009 Para/ New or Revised Wording Impact Comment Sections The construction of a valve shall be such that parts can be No Clarified historical 5.8 reassembled after being dismantled to the extent provided impact requirement. for routine maintenance. Subject: 125 Page 4 of 11 June 26, 2009 An operating or Liquid pressure-confining parts of a valve or operating parts shall have the strength and durability to provide reliable service of the parts and of the assembly, Review See Explanation for 6.2 6.1 when failure of the part allows leakage or hazardous Needed below. operation. To determine compliance comply with 6.1, a material (except a valve disc or soft seat, a seal ring, a diaphragm, or a gasket) is to have a for pressure-confining parts of a valve for direct connection to a container or having a pressure rating of 250 psig or higher shall have a Materials for fluid minimum melting point (solidus temperature) of not less confining parts of valves than 950°F (510°C) 1500°F (816°C) and a tensile strength except for valves of no less than 10,000 psi (68.9 MPa) at 400°F (204°C). identified in exception 1, having a lower melting Exception No. 1: Valves that are part of a meter assembly, point than 1500 F are not lever operated transfer valves and LP-gas hose nozzle to be allowed as noted in valves shall have a melting point (solidus temperature) of Review NFPA 58. Exception 3 6.2 not less than 950°F (510°C) and a tensile strength of not Needed allows handwheels, less than 10,000 psi (68.9 MPa) at 400°F (204°C). handles and levers on valve sizes not greater Exception No. 2: A valve disc or soft seat, a seal ring, a than ½ in pipe size to diaphragm, or a gasket is not required to comply with this have materials with less requirement. than 950 F melting point Exception No. 3: A handle or lever on a shut off service valve having an inlet connection not greater than ½ in. NPT and not directly connected to a container is not required to comply with this requirement. See Section 38. To comply with 6.1, a material for pressure-confining parts of valves having a pressure rating of less than 250 psig and for other than direct connection to a This requirement is not container, and operating parts of all valves shall th changed from the 7 have a melting point (solidus temperature) of not less than No Edition, which appeared 6.3 950°F (510°C) and a tensile strength of not impact as 5.2, but now applies to less than 10,000 psi (68.9 MPa) at 400°F (204°C). valves with a pressure Exception: A valve disc or soft seat, a seal ring, a rating less than 250 psig. diaphragm, or a gasket is not required to comply with this requirement. Changed “liquid” to “fluid” No A part in contact with the liquid fluid to be handled shall be to cover both vapor and 6.4 impact resistant to the action of such liquid fluid. liquid phases of LP-Gas and NH3 Subject: 125 Page 5 of 11 June 26, 2009 A synthetic rubber part intended to be in contact with the liquids indicated in Table 5.1 shall not show excessive volume change or loss of weight, when evaluated on the basis of its intended function, following immersion for 70 hours in the specified test liquid. See the Volume Change Test, Section 23, and the Weight Loss Test, Section 24. With reference to 6.3 elastomeric materials shall be subjected to the following tests: No change of a) Accelerated Aging Test, Section 30; requirements. Making b) Fluid Compatibility Test, Section 32; and reference to the No 6.7 c) Low Temperature Test, Section 33. performance section of impact Polymeric materials shall be subjected to the Accelerated the standard. Table 6.1 Aging Test, Section 30 and the Fluid Compatibility Test, is being moved to a new Section 32. performance section. Exception: Acetal polymers, chlorotrifluorethylene polymers, tetrafluorethylene, fluorinated ethylene propylene polymers and polyamides of composition polyhexamethylene adipamide or polycaproamide polymers (nylon 6, 6/6 or 6/16) shall only be subjected to the Accelerated Aging Test. Table 6.1 is deleted here and moved to New Section 32. No Change of requirements. Moving Paragraph is deleted here, but and moved to performance No 6.8 requirements to the section. See New Section 32 impact performance section of the standard Re-organized standard and made reference to No 6.9 Paragraph deleted and moved to performance section. tests in performance impact Section. No change in requirements Two types of shut-off valve service are contemplated by No change in these requirements: requirements, however, a) Primary Service and the paragraph is being b) Secondary Service. deleted because it is an No 9.2 Primary service valves are those suitable for installation installation requirement. impact where a positive shut-off is required. Secondary service The seat leakage test valves are those suitable for installation only in branch or describes requirements bypass piping where a positive shut-off is not essential. for secondary service valves. A shutoff valve shall not be equipped with a bypass or with a means to prevent it from closing completely. Exception: This requirement does not apply to a feature No Clarified historical 9.3 provided to permit a take-off to re-circulate fluid or to impact requirement. supply a pilot or other individually controlled outlet. Subject: 125 Page 6 of 11 June 26, 2009 For shutoff valves and shutoff valve portion of filler valves Shutoff valves with with handwheels, the handwheel and valve stem shall be handwheels and stems so constructed so that it shall not fracture, break, crack or Review 9.9 shall be subjected to the have stem threads stripped, in the open and closed Needed stem torque Test, Section position when subjected to the Valve Stem Torque Test, 39 Section 39. Documents historical New Section 10 now describes requirements for automatic requirements. Standard Section shutoff valves that use non-electrical energy to open and No th will now cover automatic 10 close valves. See 8 Edition of Standard for actual impact valves, other than wording. electrically operated 13.1 A filler valve shall incorporate one of the following: d) A positive shutoff valve with an internal excess flow No Documents historical 13.1d valve. impact requirements New Section 16 now describes requirements for multiple Documents historical Section th function valves. See 8 Edition of Standard for actual No requirements for multiple 16 wording. impact function valves. Documents historical Section New Section 17 now describes requirements for internal No th requirements for internal 17 valves. See 8 Edition of Standard for actual wording. impact valves. Documents historical New Section 18 now describes requirements for Section th No requirements for emergency shutoff valves. See 8 Edition of Standard for 18 impact emergency shutoff actual wording. valves. Documents historical New Section 19 now describes requirements for multiple Section th No requirements for lever function valves. See 8 Edition of Standard for actual 19 impact operated and LP-Gas wording. hose nozzle valves. Representative samples of each size and type of valve are to be subjected to the tests described in these requirements. When a series of shutoff or backpressure check valves are to be investigated in which the valves Documents historical differ in size only, and all sizes have the same pressure requirements. Testing of No 20.1 rating, three representative samples are to be chosen to representative sizes is impact include the largest, smallest, and one intermediate size. permitted by the Additional samples of parts constructed of nonmetallic standard. materials, such as seal materials and valve seat discs, are required for physical and chemical tests. A valve in the as-receivedcondition shall be free from leakage through stem or body seals or other joints, and shall not show evidence of porosity in castings when Revisions are editorial in tested as described in 22.2 at any aerostatic pressure nature – no change in No 22.1 between 0 and 1-1/2 times the rated service pressure of requirements. This impact the valve. change is consistent with a) 0 and 375 psi (0 and 2,588 kPa) or new 2.2. b) 0 and 1-1/2 times the rated service pressure of the valve, whichever is greater. Subject: 125 Page 7 of 11 June 26, 2009 The seat of a shut-off valve intended for primary service, Revisions to 24.2 are when in the closed position, shall be free from leakage editorial in nature – no at any aerostatic pressure between 0 and 1-1/2 times change in the rated service pressure of the valve. requirements, and are a) 0 and 375 psi (0 and 2,588 kPa) or consistent with new 2.2. No 24.2 b) 0 and 1-1/2 times the rated service pressure of the Exception to 24.2 impact valve, whichever is greater. recognizes that internal Exception: Internal valves shall be free from leakage at valves do not require any aerostatic pressure between 0 and 1.0 times test to be done at 1-1/2 the rated service pressure of the valve. times because of the seat construction. The seat of a shut-off valve intended for secondary service, when in the closed position, shall not show a rate of leakage of more than 2 cubic feet per hour (0.02 Revisions are editorial dm3/s) when subjected to any aerostatic pressure in nature – no change No 24.3 between 0 and 1-1/2 times the rated service pressure of in requirements. This impact the valve. change is consistent a) 0 and 375 psi (0 and 2,588 kPa) or with new 2.2. b) 0 and 1-1/2 times the rated service pressure of the valve, whichever is greater. A back pressure check valve provided with a resilient seat, when in the closed position, shall not leak when Revisions are editorial subjected to any aerostatic pressure between 20 psi in nature – no change (138 kPa) and 1-1/2 times the rated service pressure of No 24.4 in requirements. This the valve. impact change is consistent a) 20 and 375 psi (138 and 2,588 kPa) or with new 2.2. b) 20 psi (138 kPa) and 1-1/2 times the rated service pressure of the valve, whichever is greater. The change in A back pressure check valve provided with a metal-to- requirements is based metal seat, when in the closed position, shall not leak at No upon circumference of 24.5 a rate exceeding 1 cubic foot per minute (0.47 dm 3/s) impact seat area. Essentially 0.6 cfm/inch seat circumference when subjected to an no change in base aerostatic pressure of 20 psi (138 kPa). requirement. Seat leakage tests for shutoff valves are conducted with the inlet of the sample valve connected to a source of aerostatic pressure, with the valve in the closed position, and with the outlet open. For an internal valve, the source of pressure is applied to the container portion of the valve with the valve member in the closed position and the inlet open. For a back pressure check valve, the Clarification in test source of pressure is applied in the reverse flow No method based on type 24.8 direction. A positive shut-off valve and a pressure gauge impact of valve. No change in having a pressure range of no less than 1-1/2 times, nor requirement. more than 2 times, the test pressure are to be installed in the pressure supply piping. The pressure gauge is to be installed between the shut-off valve and the sample under test. While under the applied test pressure, observations for leakage are to be made with the open outlet submerged in water unless otherwise indicated. Subject: 125 Page 8 of 11 June 26, 2009 A manual shut-off valve, and an automatically closing, manual-reset valve, shall be capable of complying with the applicable leakage test requirements of 22.1 and 24.2, or 22.1 and 24.3, after being subjected to 6,000 the number of cycles of opening and closing under the test conditions described in 25.2 – 25.6. There shall be no sticking of the valve, nor shall the valve become inoperative. Required corrosion protection shall not be impaired. All other valves that are opened and closed using other than manual operation or having automatic features shall perform as intended for at least 100,000 cycles of operation. The test shall be performed as indicated in Table 25.1 for the various types of shutoff Clarification in test valves. There shall be no sticking of the valve, nor shall 25.1 with cycles and test method the valve become inoperative. Required corrosion No Exceptions based on type of valve. protection shall not be impaired. Rotating stem type impact 1, 2, 3 and Documents historical valves employing the stuffing box design discussed requirements. under 9.5 shall be permitted to be adjusted following the endurance conditioning and during leakage testing. Following any adjustment, the valve shall be capable of being opened and closed by hand. Exception: Rotating stem type valves employing the stuffing box design discussed under 8.4 are not required to be subjected to this test. Exception No. 1: Internal valves shall be subjected to 6,000 cycles. Exception No. 2: Emergency shutoff valves shall be subjected to 6,000 cycles. Exception No. 3: Excess flow and back pressure check valves are not subjected to this test. Number of cycles for shutoff valve types Number of Valve type cycles Manual Valves, Internal Valves or Emergency Shutoff Valves, with or Clarification in test without Actuators, and automatic 6,000 cycles and test method closing, manual reset valves No Table 25.1 based on type of valve. impact Documents historical Lever Operated Fuel Transfer Valves requirements. 30,000 LP-Gas Hose Nozzle Valves and All Other Shutoff Valves With Actuators, 100,000 and Automatic Shutoff Valves Subject: 125 Page 9 of 11 June 26, 2009 A shut-off valve for use only with LP-Gas that has a Revisions now allow pressure rating of 250 psi (1.7 MPa) gauge or higher, or valves to be rated at one for use with either LP-Gas or anhydrous ammonia, 125 psig. Changes to is to be tested with the valve outlet plugged, the valve No this paragraph clarify 25.3 body filled with n-hexane, and the valve inlet subjected impact testing to the correct to a pressure of 250 psi (1.7 MPa) gauge. If the shutoff pressure rating. This valve for LP-Gas service has a rating of 125 psig, the change is consistent test is conducted with n-hexane and the valve inlet with new 2.2. subjected to a pressure of 125 psi (0.9 MPa) gauge. An endurance test is to be conducted at a rate no faster than 10 times per minute. For a shut-off valve, the closing torque is to be consistent with the size of the No Clarifies historical 25.5 handwheel, wrench, or other means used to operate the impact requirement valve. Shutoff valves with an adjustable packing nut are allowed one adjustment during the endurance test. Revisions now allow valves to be rated at A valve shall be capable of withstanding, without rupture 125 psig. Changes to or permanent distortion, a hydrostatic pressure of 1250 No this paragraph clarify 26.1 psi (8.6 MPa) or 5 times the rated service pressure of impact testing to the correct the valve, whichever is greater. See 2.1 Service pressure rating. This Pressure Rating, Section 2 change is consistent with new 2.2. There were many minor changes to the Operation Test method, which clarified historical methodologies, such as, the flow rating is the average of all trials in all flow Clarifies historical No Section 27 directions, small valves are permitted to have vapor requirements and impact rating only, clarification to instrumentation and flow test methodologies. th equipment and other minor changes. See New 8 edition, Section 27 for actual wording changes. Volume Change Test Method is being deleted because No No change in Section 29 the test method is covered by UL157, which is now impact requirements. referenced in Section 32. No change in Accelerated aging test is now covered in this section, requirements. This No Section 30 under the performance section of the standard. It was section now documents th impact taken from Section 5 of the 7 edition. historical requirements for polymeric parts Weight Loss Test is being deleted because the test No No change in Section 31 method is covered by UL157, which is now referenced impact requirements. in Section 32. No change in th requirements. This New Section 32 was taken from Section 5 of the 7 No Section 32 section now documents edition. impact historical requirements for polymeric parts Subject: 125 Page 10 of 11 June 26, 2009 When the elastomeric part does not comply with the requirements in 33.1, the following alternate test may be conducted. One complete valve assembly is to be placed in a cold chamber maintained at minus 40 2°F Changes to this test (minus 40 1°C) for 24 hours, removed, manually method recognize that operated for 25 cycles consisting of complete opening LP-Gas and NH3 have and closing, and then returned to the cold chamber for 1 No a much lower pressure 33.3 hour. (When the elastomeric part is a static seal, the 25- Impact at –40 F temperature. cycle operation test is not conducted.) Immediately after The test pressure is the 1 hour exposure, the valve assembly is to be consistent with this subjected to the External Leakage Test, Section 22, and temperature. the Seat Leakage Test, Section 24, as appropriate, using a test pressure of 30 psig. The leakage rate shall comply with the requirements specified for these tests. Documents historical Documents Thermal Link Operation Test. See new No Section 35 requirement and test edition for specific wording. Impact method. Documents historical Documents Fire Test. See new edition for specific No Section 36 requirement and test wording. Impact method. Documents historical Documents Drop Test. See new edition for specific No Section 37 requirement and test wording. Impact method. Documents historical Documents Impact Test. See new edition for specific No Section 38 requirement and test wording. Impact method. 39.1 Six production samples shall be tested, three each in the opened and closed position. Each sample shall comply with 9.9. The torque in in-lbs that shall be applied to each sample shall be in accordance with the following equation: New Torque Test for T = 50 X D (handwheel diameter in inches) Review Section 39 shutoff valves with 39.2 A torque wrench shall be applied to each of 3 Needed handwheels. sample valve handwheel and torque be applied in the closed position. A torque wrench shall be applied to each of 3 sample valve handwheel and torque be applied in the opened position. 41.1 c) The rated service pressure when the rating is not in UL Listings have not excess of 250 psi (1.7 MPa), and No previously covered 41.1 c and e d) The direction of flow, when not evident. Impact valves covered by par. e) Valves for secondary service, in accordance with 9.2 41.1 (c) or (e). and 24.3 shall be so marked. Subject: 125 Page 11 of 11 June 26, 2009 Each excess flow valve shall be marked with its rated closing flow capacity in gallons per minute (m 3/s) of liquid anhydrous ammonia or LP-Gas (propane), or both, when appropriate. An excess flow valve having only a vapor rating in accordance with the exception to 27.2 shall have its flow capacity in cubic feet per hour or No Clarifies historical 41.2 liters per minute of gaseous anhydrous ammonia or LP- Impact requirements. Gas (propane), or both, when appropriate marked on the valve. When the rated closing flow used to determine compliance with 27.1 is dependent upon mounting position, the marking shall include reference to the direction of flow mounting position. All markings shall be legible and permanent, such as afforded by metal stamping, by molding in a casting, or by a metal nameplate, or printed on a pressure sensitive label(s) secured by adhesive. To determine when a pressure-sensitive label, or label secured by cement or adhesive is of a permanent nature, representative No Clarifies historical 41.3 samples are to be subjected to exposure conditions for Impact requirements. outdoor use (standard atmospheric, water immersion, oven aging, low temperature, ultraviolet light, and water exposure), in accordance with the Standard for Marking and Labeling Systems, UL 969. For a nonself-closing type valve, the appropriate operating positions or the direction of movement shall No Clarifies historical 41.6 be clearly indicated for a manual operating lever or reset Impact requirements. handle.
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