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Bending The Line

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					The Medellin Project in Colombia


           Philippe Adrien
            Export Director
            Pomagalski SA




                              Page – 13.1
Abstract:


                              The Medellin Project in Colombia
                                            Philippe Adrien 1 )


The municipal council of Medellin has chosen the gondola lift solution to connect the hillside
district of Santo Domingo to the city's overground metro network. The MetroCable project, as it
is called, is jointly funded by the city and the mass transit company, Metro Medellin.

The system is an ARIANA 8-10 gondola lift from the SATELLIT range, equipped with
aluminum DIAMOND gondolas made by SIGMA. The line is scheduled to run 18 hours/day, all
year round. It is 2 km long, with a vertical rise of 400 meters, three sections and four terminals,
including two intermediate stations, the first of which includes a 15° turn. Ground on which the
lift is built calls for extremely deep anchoring for the single-shaft towers, each of which rests on
four piles, with a diameter of 2 m, driven down to a depth of 8 meters.




1
 Export Director, Pomagalski SA, 109 rue Aristide Beregs, BP 47, Voreppe Cedex, F-38341, 33 4 7628 7146, Fax
33 6 7399 5702, philippe.adrien@poma.net


              Page – 13.2
        A New Application of the Aerial Ropeway Transportation Technology
                 METROCABLE in MEDELLIN - COLOMBIA
                                           Philippe ADRIEN1




A. PRESENTATION:

          1. MEDELLIN:

                  a. Located at an altitude of 1,200 m, Medellin is COLOMBIA second largest
                     city and a major economic center of this country of 50 million people.
                  b. MEDELLIN is famous for its coffee its clothes manufacturing along with an
                     important role played in the fashion business. The city also hosts some large
                     foreign companies such as car manufacturer Renault which activities cover the
                     whole Andes Community of
                     Nations (CAN).
                  c. The city is located along a river
                     and stretches for 25 km from
                     North to South surrounded by
                     high crests some 800 meters.
                  d. In order to cope with this
                     specific            mountainous
                     environment of the city some
                     important infrastructures have
                     been realized lately. Most of • The Metro Medellin network after the
                     them are dedicated to traffic         completion of the cable car extension

                     and      urban     infrastructure
                     improvement.

          2. METRO MEDELLIN:

                  a. The mass transportation system is an over-ground metro linking various
                     places and suburbs along 3 main lines.
                  b. The Metro counts 30 km of tracks, some 25 stations.
                  c. It is supported by the City of MEDELLIN and the Government of
                     COLUMBIA since it is considered as a very important tool of social
                     development.
1
    Export Director, POMA, BP 47 F-38341 VOREPPE Cedex, T: 33-0476287146, Fax: 33-0476287191
    E-mail : philippe.adrien@poma.net



                                                                            Page – 13.3
3. HISTORY of the PROJECT:

     a. One of the major problems the Metro has to face is the lack of passenger
        traffic at its northern part of the network. Populations in these areas are poor
        and      leave     in    typical
        “barrios”. They prefer to use
        traditional       means       of
        transportation such as taxis
        and small buses, only
        capable to cope with the
        narrow and tortuous streets.
        In addition, ground profile
        does not allow using any
        traditional      and      viable
        solution to reach potential
        clients.
     b. This is why the Municipal council of MEDELLIN has chosen the gondola lift
        solution to connect the hillside district of Santo Domingo to the City Metro
        Network. The MetroCable
        project, as it is called, is co-
        funded by the City and the
        mass transit company, Metro
        Medellin.
        The contract was signed with
        POMA on March 31st, 2003
        for the supply of an
        ARIANA 6-10 gondola lift
        from the SATELLIT range,
        equipped with aluminum
        DIAMOND gondolas made by SIGMA. With a ceiling height of 2.10 m, each
        of the 93 gondolas has room for 8 seated or 10 standing passengers, and
        includes a radio and battery-solar powered lighting for nighttime operation.
        The line is scheduled to run 18 hours/day, all year round.
        It is 2 km long, with a vertical rise of 400 meters, 3 sections, 4 terminals, and
        2 intermediate stations, the first of which includes a 15° angle.

4. THE SANTO DOMINGO AREA:

        Located in the SANTO
        DOMINGO built-up area,
        construction of the lift
        required the issue of a
        number      of   compulsory
        purchase orders on various
        properties. In addition, the
        ground on which the lift is



    Page – 13.4
                built calls for extremely deep anchoring for the single-shaft towers, each of
                which rests on 4 piles, with a diameter of 2 m, driven down to a depth of 8
                meters.

                Three companies have formed a Joint Venture to complete the project:
                   • POMA to supply
                       the       lift,    the
                       supervision         of
                       erection          and
                       necessary training
                       for maintenance and
                       technical operation.
                   • CONCONCRETO
                       for all civil works.
                   • TERMOTECNICA
                       for the erection and
                       supply of local
                       fabrication (structure, roofing…).


B. LIFT MAIN TECHNICAL CHARACTERISTICS:

  The line is scheduled to operate 18 hours/day, 365 days/year. Even though there is no
  specific requirement by Metro Medellin for POMA to guarantee a minimum availability, the
  lift has been designed so that it is capable to remain operable in case of a problem in the
  drive machinery. 2 electric motors in tandem configuration are ensuring the maximum
  service (base/degraded). The maintenance has also been rescheduled to fit with the large
  number of hours the lift is expected to operate every year. The lift consists in:

     1. Mechanical Equipment:

         o   4 stations, single loop, single drive located at the lower terminal
         o   Tensioning located at upper terminal
         o   Garage for the 93 cabins located at lower terminal
         o   Length:                                     2,000 m            6,000 ft
         o   Vertical rise                               4,000 m            1,320 ft
         o   Number of stations                          4
         o   Capacity (base/degraded):                   3,000 pph / 1,500 pph
         o   Rope diameter:                              51 mm              2”
         o   Angle at the level of station Nr. 1:        15°
         o   Number of cabins:                           93
         o   Type of cabins:                             DIAMOND 8/10, 2.10 m ceiling height
         o   Installed power:                            2 x 455 kW
         o   Volume of concrete in civil works:          17,000 m3
         o   Rope speed (base/degraded)                  5 m/s / 2.5 m/s




                                                                   Page – 13.5
         o Power is taken from the rope for acceleration and deceleration ramps in both
           terminals
         o Transfers in intermediate stations are electrically powered
         o In both terminals, cabins cadencing system is electrical in base and degraded
           operation conditions.
         o Braking is standard:
                  One service brake
                  One emergency brake

     2. Electrical Equipment:

         o The terminals (drive and
           return) are controlled by a
           safety automate (S7 – 400F by
           Siemens) equipped control
           system (SEMER design and
           fabrication).
         o The 2 intermediate stations are
           controlled by a separate safety
           automate (S7 – 400F by
           Siemens) equipped control
           system.
         o Both automate cabinets are
           located in bottom terminal.
         o The lift can be controlled from each station by remote control.
         o Diagnosis and trouble shooting can be performed remotely from POMA in
           France.
         o Fully automated garage is also controlled by its dedicated automate.


C. MAIN ECONOMICAL DATA:

         o Total value of the investment:                25 Millions US Dollars
         o Cost of electro-mechanical equipment:         12.7 Millions US Dollars

         o Pre-project duration:                         3 years
         o Project completion time:                      16 months

         o Price of the metro passenger ticket:          30 cents


D. DESCRIPTION OF THE LIFT:

  The metro system follows the river valley where Medellin City has developed. The purpose
  of the project is to create a “feeder line” connecting the area of Santo Domingo to the metro
  station of ACEVEDO as shown on the following picture.



           Page – 13.6
•   The Metro Station of ACEVEDO where the existing metro network (on the bottom) connects with the Santo Domingo gondola lift
    line. Garage for the 93 gondolas is also visible on this picture.




                                                                                          Page – 13.7
1. Bottom Terminal:

      •   ACEVEDO:
          It is the drive terminal. It is also equipped
          with the fully automatic garage for the 93
          gondolas with retractable platform.




2. Intermediate Station Nr 1:

      •   ANDALUCIA:
          The line makes an angle of
          15°. This deviation is made
          with sheave batteries.
          Embarkation /
          disembarkation of
          passengers are possible in
          both directions.




3. Intermediate Station Nr 2:

      •   POPULAR:
          The line goes straight through this
          station. Embarkation / disembarkation
          of passengers are possible in both
          directions.




     Page – 13.8
4. Top Terminal:

      •   SANTO DOMINGO:
          This is the return and
          tensioning terminal. Stress
          gauges are used to control
          the tension value applied
          by the hydraulic circuit.
          Embarkation /
          disembarkation of
          passengers are possible in
          both directions.


5. The Line:

      •   The line is 2,000 m long
          with a vertical rise of 400
          m and an angle of 15° at
          the level of intermediate
          station Nr. 1. It comprises:
              o 23 towers
              o Rope diameter: 51
                  mm
              o 3 sections
              o Double safety line


6. The Cabins:

      •   There are 93 passengers
          cabins as follows:
             o DiamonD 8/10 type
                 2,100 mm ceiling
                 height
             o 10 passengers
                 standing of 8 seated
             o Interior lighting
                 with batteries and
                 solar panels
             o Full duplex
                 passenger
                 communication
                 devices between the cabins and the drive terminal.




                                                             Page – 13.9
E. SPECIAL FEATURES:

  There are several points, which have been reconsidered taking into account the use of this
  technology to be integrated in an urban transportation system.

     1. Availability:

            a. The drive unit is designed so that the occurrence of a total shut down of the
               lift in case of mechanical or electrical problems is as minimized as possible.
               Base operation is made at 5 m/s rope speed:
                    • There are 2 electric motors M1 and M2 used together to reach the 5
                        m/s rope speed in normal operation, each motor delivering half of the
                        requested power.
                    • These 2 motors are connected with U joint to the POMA/KISSLING
                        main gearbox.




           Page – 13.10
b. In case of electric failure caused by one electric motor or one power supply
   cabinet, the lift is operated in degraded mode at 2.5 m/s:
       • The mechanical integrity of the 2 electric motors M1 and M2 is
          preserved but only one (M1 or M2) is available.
       • An intermediate temporary gearbox (ration ½) is inserted between the
          2 motors and the POMA/KISSLING main gearbox.
       • The operation is possible at 2.5 m/s until the next maintenance
          operation to repair the electric failure or replace the damaged motor.




                                                    Page – 13.11
 c. If electric motor M1 is mechanically damaged:
        • The U joint between M1 and M2 is removed and tachometer is moved
             from M1 to M2.
        • M2 is connected to the POMA/KISSLING main gearbox via the
             intermediate gearbox (ration ½).
        • Operation is possible at 2.5 m/s until the next maintenance operation to
             replace M1.




Page – 13.12
d. If electric motor M2 is mechanically damaged:
       • The U joint between M1 and M2 is removed and M2 is moved to the
            side.
       • M1 is connected to the POMA/KISSLING main gearbox via the
            intermediate gearbox (ration ½) and a long U joint.
       • Operation is possible at 2.5 m/s until the next maintenance operation to
            replace M2.




                                                     Page – 13.13
      e. The lift is also equipped
         with 2 safety lines to
         guarantee the monitoring of
         the line in all conditions.
           Both are activated in
           normal operation. In case
           one is out of order, it is
           possible to operate with
           one line only until the
           next           maintenance
           operation.


2. Maintenance:

   The contract includes a 3 months technical assistance period to train the client’s
   personnel in actual operation and maintenance conditions.

   Further assistance can be provided by POMA after the completion of these first 3
   months upon client’s request.

   POMA has delivered with the lift a complete set of documents including:
       • As built drawings
       • Description of each main assembly
       • Maintenance manuals
   to ensure a perfect knowledge of the lift design. This is also helpful for parts
   identification and ordering by the client.

   Maintenance program has been adapted to the actual operation conditions:
        • There are 4 stations, each with embarkation/disembarkation capabilities in
            both directions. A grip supports 6 opening/closing cycles for each travel.
        • The lift is operated 6,500 hours/year to be compared with an average of 1,500
            hours/year in a ski resort.
   The next table shows some examples of adapted maintenance program for some
   critical components.

   A set of critical and long delivery time components has been sold with the lift:
      • 3 cabins are kept in stand by in the garage.
      • One POMA/KISSLING main gearbox;
      • One electric motor.




    Page – 13.14
•   Example of a page of the maintenance manuals. The up dating of the maintenance manuals and technical
    notices can be done directly by the client downloading the latest issue on www.poma.net.




                                                                            Page – 13.15
                                                                              Standard Periodicity
                  Operation to be
Components                                    Medellin Periodicity            (according to French
                    performed
                                                                                     code)

                Braking test no load                 6 months                            N/A

  Brakes

               Braking test full load                 Yearly                           Yearly


                   Magnetoscopic                                              After 1st, 4th, 7th, 10th,
   Rope                                              6 months
                    inspection                                                15th year, later yearly


  Grips             1st inspection         One year and after yearly                   5 years




   Cabin                                                                    20,000 hours or 15 years
                   Integrity check              Every 18 months
 Structure                                                                   whichever occurs first




   •   Example of some critical components, maintenance program of which has been adapted to the actual
       operation conditions.




           Page – 13.16
3. Safety of Operation:

   a. In case of complete failure such as:
          • No more electrical power
          • Main failure of the main POMA/KISSLING gearbox
          • Both electric motors M1 and M2 are damaged
      emergency procedure is activated:
          • The main POMA/KISSLING gearbox and the bullwheel are uncoupled,
          • 2 hydraulic motors are coupled to the bullwheel through the crown gear.
              High-pressure oil comes from a hydraulic pump activated by a diesel
              engine.
      Passengers reach the next station at a speed of 1 m/s.




                                                         Page – 13.17
b. Cabins are equipped with a full duplex addressing device powered by batteries
   and solar panel so that passengers can send information and receive instruction in
   case of emergency.

c. Since the lift has a limited clearance to the ground, it is always possible to
   vertically evacuate people in extreme situation in less than 3 hours.

   Medellin Fire Brigade and dedicated Metro teams have been trained to this
   purpose.




 Page – 13.18
F. SOME KEY POINTS for SELECTING A CABLE CAR:

  Here are some reasons why clients select this product for urban transportation:

             •   The investment cost is low compared to other mass transportation systems.

             •   It minimizes ground occupancy.
             •   It allows easy crossing of rivers and other natural obstacles at reasonable cost
                 (no big infrastructure required).
             •   It allows easy access to mountainous areas.
             •   It is environment friendly.

             •   Quiet operation is guaranteed in inhabited areas.
             •   It offers a great flexibility of operation.
             •   Maintenance costs are optimized.

             •   It is a proven technology used in thousands of lifts, most of them installed in
                 extreme environmental conditions.


G. OTHER PROJECTS:

  There are other projects at different stages of development in the world.

     1. ESPARAGUERRA:

         This project is under construction by POMA in the suburb of BARCELONA in
         Spain. It is made of a jig back system with 2 cabins of 16 passengers with a capacity
         of 200 pph to
         be increased
         to 400 pph in
         the future by
         adding         2
         cabins.     The
         lift is 1,300 m
         long with a
         vertical rise of
         100 m. It
         connects       a
         train station to
         a new urban
         development
         accessible
         only by a
         difficult road.



                                                                     Page – 13.19
2. KAOSHIUNG:

  The project under development consists in the extension of existing metro lines
  KTRC 01 and LRT G1B into the harbor of Kaoshiung.
  One line (in yellow interrupted line) will use a mono-cable gondola lift while the
  other (red interrupted line) will need the use of multi-cable technology.




   Page – 13.20
H. CONCLUSION:

  The lift has been inaugurated on July 30th, 2004 by the President of the Republic of
  COLOMBIA in the presence of the Mayor of MEDELLIN and the Governor of the Province.
  It has entered commercial exploitation since August 7th, 2004.

  Here is a selection of some very representative pictures of the final installation.




   •   The drive terminal upstairs the ACEVEDO metro connection station.




                                                                           Page – 13.21
•    The gates to MetroCable boarding platform.




•    The drive terminal embarkation/disembarkation platform.




    Page – 13.22
•   The first section of MetroCable line viewed from ACEVEDO terminal.




•   The main reason of shut down, kites.




                                                                         Page – 13.23
•   The whole line view from a cabin in the third section.




         Page – 13.24
                        History of the Detachable Grip


                                           Jon Mauch
                                           Lift Director
                                Breckenridge Resort, Keystone Resort




Jon started at Breckenridge in 1977 and have work through various jobs in the lift department.
Currently he is the Lift Director with responsibilities of Lift Operations, Lift Maintenance, Lift
Construction and Planning, and Ticket Scanning. We have installed many unique and different
types of lifts, including the worlds first detachable quad, a fixed grip lift with a 45% turn, a
double loading six passenger lift, the first conveyor lift for kids ski school, and have
experimented with different types of loading configurations including loading conveyors and
contour loading.

I have participated with the Colorado Passenger Safety Board as a Technical Committee Member
and served as chairman on numerous ad-hock committees. I also served on the Rocky Mountain
Lift Association board.

I have been an ASC B77 Committee Member since 1991. In May 2001, I assume the
Chairmanship of the committee. I have worked the better part of my life in the Tramway
business and am very dedicated to promoting safety and innovation. This is more than just a job
for me, I truly enjoy the interface with tramway people throughout the world.




                                                                        Page – 14.1
Abstract:



                                   History of the Detachable Grip
                                                 John Mauch 1


This is a historical look at the detachable grip. We will look at the development and theories of
Detachable Grips as the progressed from gravity to the grips we use today.

Many of the grips started out in the mining industry and migrated to passenger usage. Through
the use of drawings and photos we will be able to see the progression and changes to grips as
they work in today’s systems.




1
    Lift Director, Breckenridge & Keystone Resorts, PO Box 1068, Breckenridge, CO 80424, (970) 453-3289
    F (970) 453-3202, jon@vailresorts.com


                 Page – 14.2
                       Utility Conduits Suspended Between
                                 Ropeway Towers


                                             Chuck Peterson, P.E.
                                                   President
                                              Tramway Engineering




The author was the design engineer for the Iron Mountain Tramway project including all aspects of the utility lines.
He was also one of the project owners and is the president of Tramway Engineering, a consulting firm specializing
in ropeways.




                                                                                     Page – 15.1
Abstract:



                   Utility Conduits Suspended Between Ropeway Towers
                                            Chuck Peterson, P.E. 1


The presentation will be based on experience gained in the installation of a natural gas, potable
water and wastewater utility lines on the Iron Mountain Tramway in Colorado. We will look at
the design construction, and operation of the utility lines that are suspended between the tower
heads.




1
    President, Tramway Engineering, P.E., P.O. Box 398, Glenwood Springs, Colorado 81601 USA.
    (970) 945-5138 chuck@tramway.net


                 Page – 15.2
                   Utility Conduits Suspended Between Ropeway Towers
                                            Chuck Peterson, P.E. 1


Tourist tramways are often used to provide access to remote locations in mountainous terrain. In
many cases, the upper terminal is a multiuse facility that requires basic utilities such as electrical
power, water, natural gas and sewer. Fortunately, in most cases, these utilities can be
economically provided by direct burial of the utility lines. However, the use of aerially supported
utility lines can be considered in those rare conditions where traditional buried lines are either
environmentally, economically or physically impracticable.

                                                             In 2003 aerial utilities lines were installed
                                                             on the fixed grip pulse gondola
                                                             manufactured and installed by Leitner
                                                             Poma of America. The ropeway has a slope
                                                             length of 4433 ft (1351m) and a vertical rise
                                                             of 1352 ft. (412m). As installed, there are
                                                             four groupings of two 6 passenger gondola
                                                             cabins. Ultimate design capacity is 12
                                                             groupings of 3 carriers.

                                                             The ropeway accesses a multifunctional
                                                             upper terminal at the Glenwood Caverns in
                                                             Glenwood Springs, Colorado. The utility
                                                             lines provide potable water, natural gas and
                                                             gray water disposal for a 13,000 ft2 (1,207
                                                             m2) upper station that includes a 150 seat
                                                             restaurant, a 1200 ft2 (111 m2) gift shop and
                                                             support facilities. The tramway is operated
                                                             year round. A mountain roadway provides
                                                             limited year round access to the upper
                                                             terminal.

                                                             During the first 18 months of operations the
                                                             utility lines have proven to be an acceptable
                                                             alternative to the traditional buried lines
                                                             with certain limitations.




1
    President, Tramway Engineering, P.E., P.O. Box 398, Glenwood Springs, Colorado 81601 USA.
    (970) 945-5138 chuck@tramway.net


                                                                                Page – 15.3
Design and Construction

Support Cable. The three utility lines (natural gas, water and gray water) are supported by a
7/16” (12 mm) IWRC EIP cable suspended directly under the tower crossarms. The selection of
the cable size took into consideration live and dead loads of the utility lines, wind and the sizing
of the available cable hangers. It was decided to use a standard 3 bolt guy clamp to connect the
utility hanger to the support cable. A 7/16” cable was selected because it was the largest size
cable that was compatible with this clamp. The factor of safety was designed for the longest span
of 442 ft (135 m) with a 3% sag ratio. Local climatic conditions did not require that icing be
taken into consideration. The support cable has a factor of safety of 2.5 when the utility lines are
full with a 70 mph (112 km/hr) crosswind.

Clearance between the utility lines and the carriers must be taken into careful consideration. The
assumed 3% sag ratio has resulted in less clearance than was anticipated. Although the ropeway
haul cable was designed for a maximum 3% sag ratio, the sag of the haul rope on individual
spans varies depending on the installed number of cabins within the pulse group and the loading
of the cabins. In retrospect, the sag of the utility lines should have been designed to be less than
the haul rope sag under the lightly loaded conditions of the initially installed capacity. Because
the support cable is secured to each tower crossarm, these conditions may require that the
incoming and outgoing support cable tensions differ. In these cases, the additional torque on the
tower tubes and connections must be considered.

The cable was connected directly under the
crossarm at a point adjacent to the tower tube
for clearance issues and to reduce the amount
of torque on the tower tube. Although
installing the connection point on the lifting
frame would have improved clearance, it was
decided that the additional moment arm above
the crossarm created unacceptable stress. The
support cable was pulled from the upper
terminal to the lower terminal across nylon
rollers on each tower at the connection point.
Once the cable was tensioned to provide a 3%
sag ratio for the longest span, the cable was
secured to each tower with strand vices.




             Page – 15.4
Utility Conduits. The utility conduits are three 1-1/2” (38 mm) inside diameter fiberglass
reinforced plastic tubing that is commonly used in the petroleum industry. The connections are
integral threaded and coupled. The pipe which was manufactured by Star Fiberglass 2 has been
tested to confirm that there was no structural deterioration caused by ultraviolet radiation over
the five year test period. The rated pressure for the pipe that was used on the project was 2000
psi (137 bars) for the lower section of the profile and 1500 psi (103 bars) for the upper half of the
profile. The ultimate burst pressure rating for the lower section was 5000 psi (344 bars)

The pipe had been certified by a European testing agency for use in the transport of potable
water. There was no similar United States certification available. The authorities having
jurisdiction allowed the pipe to be use for this application in spite of no United States
certification with the understanding that the pumped water would be tested monthly to confirm
acceptable water quality.

The pipe was connected to the support cable at 10
ft (3 m) intervals. The connection was made
with three bent plate parts that were bolted
together to form a triangle. The triangle was
bolted to the support cable with a 3 bolt guy
clamp. The bent plates surround and lock into
place a rubber gasket. The gasket was made by
extrusion to match the profile of the three pipes.
The goal was to ensure that the steel triangle
would not contact the pipe and possibly cause
abrasion. A communications line, which was
electronically connected to the lift control system,
was attached to the utility line to monitor the line
integrity.

The pipe was installed in 30 foot (9.1 m) sections. The pipes were assembled into the support
hangers before being placed into a rack that was suspended between two work carriers. The
pipe laying crew started at the upper terminal and worked downhill on the light side. Each pipe
assembly was attached to the support cable and then each pipe was mated with the uphill
assembled pipes. The pipes were screwed together with a fabric pipe wrench to the
recommended torque. Once the pipes were secured, the bolts on each hanger support were
tightened to squeeze the triangular frame around extruded gasket. The entire process took about
three weeks to complete.




2
 Star Fiberglass http://www.onr.com/star/PDF/E5000.pdf . Web site contains technical design criteria for the
fiberglass pipe used in the project.


                                                                                    Page – 15.5
Utility Connections. Steel utility pipes were attached directly to the first and last towers for the
connection to the underground utilities. At the top of the terminus, reinforced rubber hoses were
used to transition to the fiberglass pipes. This flexible connection allowed for movement
between the suspended lines and the fixed steel lines attached to the towers.

A special bracket was fabricated for the crossarm on the first tower for the gray water line. The
bracket was designed to act as a thrust block for the gray water as it transitioned from a high
velocity flow within the fiberglass line to the steel line attached to the tower.

Vacuum breakers were attached to the lines at the upper terminus to allow for air to enter the
lines during water drain back. These vacuum breakers were wrapped with heat tape for winter
operations.

Operations

Waterline. The only source of potable water for the operation of the upper facility is the aerial
waterline. During peak summer operations, approximately 5000 gallons (19,000 l) per day are
used. This demand is reduced to about 2000 gallons (7570 l) per day during the winter.

Water is pumped from the base terminal directly to a 34,000 gallon (128,000 l) holding tank
located vertically 157 ft (47 m) above the upper facility. Water gravity feeds the building with a
static water pressure of 68 psi (4.6 bars). The holding tank provides for a 17 day water supply in
the winter when the waterline may not be operational due to cold temperatures.

When the system was commissioned, the water was pumped by two positive displacement
pumps at a rate of 30 gpm (113 lpm) with a total head of 1000 psi (69 bars). These pumps were
subsequently replace with a single 37 stage centrifugal pump with a flow rate of 42 gpm (159
lpm). Since water is drained from the line during colder temperatures, the piping system was
designed to allow for drainage water to bypass the pumps to prevent pump damage.

Since the waterlines is not insulated, pumping in the winter is problematic and requires careful
monitoring. If the water in the pipe was to freeze, there would be no technique that could thaw
the pipe and prevent the frozen water from splitting the pipe. The upper tramway terminal is
located at an elevation of 7100 ft (2164 m). An analysis of 100 years of daily temperature
records for Glenwood Springs, Colorado with an elevation of 5700 ft (1737 m) shows that the
average January monthly maximum temperature is 36.9 °F (2.7°C). Only the first ten days of
January have an average daily maximum temperature (with a 68% confidence level) below 32 °F
(0°C). Therefore, it is statistically possible to pump water during the coldest month. However,
during colder winters or during extended stretches of cold temperatures, there are periods where
pumping is not possible.




             Page – 15.6
In order to monitor the water temperature, a waterline temperature gauge was installed at the
upper terminal for the upper attendant to monitor conditions when pumping. Pumping was
suspended when the incoming water temperature was 38°F (3.3°C). By suspending pumping
operation at this point, there was sufficient latent heat to allow the water in the line to be drained
back to the lower terminal before it reached the freezing point. With the initial incoming water
temperature of 50°F (10°C) it was possible to continue to pump when the air temperature was
28°F (-2.2°C).

Even with careful monitoring of the pumping parameters, it was a challenge to keep the water
level in the reservoir tanks to an acceptable level during the month of January. Although there
was often a period of time during the day when pumping was possible, the total quantity of water
pumped was dependant on the length of the pumping window. During the first winter of
operation water levels in the tanks remained adequate for normal operation in the facilities even
though there were days when pumping was not possible.

Gray Water. When the system was commissioned, there was no waste water disposal system at
the upper facility. All waste water was conveyed to the lower terminal via the aerial pipelines
for disposal by the local municipal waste water treatment facilities. Due to the small size of the
aerial pipes, waste water was pretreated at the upper terminal to remove the solids. Waste water
at the upper facility was pretreated with two 2500 gallon (9460 l) septic tanks installed in series.
Solids were collected in these tanks and pumped from the tanks twice a year by pumper trucks.

Pretreated sewage was collected in a 5000 gallon (18,900 l) storage tank at the upper facility. A
high water level sensor within the tank would start to pump the sewage to the top of the terminus
tower. Pumping would continue until the low level sensor turned off the pump. The intent was
to provide intermediate pumping of the sewage at higher flow velocities in order to avoid
freezing of the downgoing sewage. It was assumed that water flowing at a high velocity had
sufficient energy to prevent freezing even at low temperatures. This assumption proved to be
incorrect. During the first winter, the automatic pumping during low temperatures resulted in a
freeze up of the gray water in the utility line. Fortunately a warming trend allowed the line to
thaw within a couple of days. Following the event, the sewage was only pumped when the air
temperature was above freezing. In order to avoid a reoccurrence of this event, a 2000 gallon
(7560 l) per day septic system was installed during the 2004 construction season to allow all
sewage to be disposed of on mountain during the winter months when demand is limited.

Because the upper facility includes a 150 seat restaurant, the waste water includes a grease
component. There was great concern that grease could accumulate on the walls of the aerial
lines and eventually totally clog the line. In order to avoid this occurrence, all waste from the
kitchen passed through a grease trap which was periodically pumped and hauled off the
mountain. As an additional precaution, enzymes were added to the grease trap in an attempt to
keep the grease in suspension. During the first summer of operations, there were indications that
even these precautions were inadequate to prevent grease from accumulating on the walls of the
utility line. Since there are limited options available to clean grease from the lines, the build up


                                                                          Page – 15.7
of grease was a major concern. Ironically, the first winter of operations provided an unexpected
solution to the problem. Apparently night time temperatures during the coldest months of the
winter froze the accumulated grease that lined the pipe walls. It appears that the frozen flakes of
grease were flushed down the lines when waste water was periodically pumped down the utility
lines. A change in the type of enzymes used in the grease traps during the second summer of
operations has apparently reduced the buildup of grease in the lines.

Natural Gas The transportation of natural gas on aerial lines attached to a ropeway could be
perceived as a safety issue. The authority having jurisdiction had concerns that if the line
ruptured and the gas was ignited, a blow torch effect may endanger the passing carriers or the
haul rope.

The incoming static pressure of the natural gas was about 50 psi (3.4 bars). The factor of safety
for the 1500 psi (103 bar) fiberglass pipeline therefore was about 30:1 for rupture. The total
volume of natural gas in the line is 54 cubic feet (1.5 cubic meters). Because of these factors it
was decided that the risk to the tramway was minimal.

As a safety feature, a valve was installed on the supply line that would shut off the flow of the
natural gas if there was a sudden drop in downline pressure. In addition, on an annual basis, a
pressure test is conducted on the gas line whereas the line is isolated and the pressure in the line
monitored to determine if there is any loss of pressure during the test. If there was a loss
observed, the line would be inspected to detect the odor that is added to the natural gas.

Conclusion. The use of aerial utilities on a ropeway has proven to be successful. The lines have
been in operation for about 18 months with no major problems. Based upon the experience of
the aerial utility lines at the Iron Mountain Tramway, the following observations can be made.


   1. Aerial utility lines are not as reliable as the traditional buried lines. The aerial lines are
      subject to more operational and atmospheric variables that could effect the functionality
      of the utilities that are critical for the operation of the upper facilities.
   2. Under most conditions, aerial water lines should only be installed in warmer climates
      where freezing temperatures will not become a threat to the lines.
   3. If an aerial water line is used, there must be a reservoir at the upper facility large enough
      to supply water for a reasonable amount of time if the utility line is temporarily not
      available.
   4. The use of aerial utilities is not practical in areas where icing is possible. The cross
      sectional area of the lines could result in an ice load that is not supportable by any
      reasonably sized support cable.




             Page – 15.8
    5. The use of an aerial gray water disposal line must be limited to times when the
       atmospheric temperatures are above freezing. High velocity flow is not adequate to
       prevent freezing of the gray water in extremely low temperature conditions.
    6. If the upper facility includes a kitchen, extreme care must be taken to pre-treat the gray
       water to remove all grease that could accumulate on the walls of the line and eventually
       render it non-functional.


1
 Author, Charles R. Peterson P.E., P.O. Box 398, Glenwood Springs, Colorado 81601 USA. (970) 945-5138
chuck@tramway.net The author was the design engineer for the Iron Mountain Tramway project including all
aspects of the utility lines. He was also one of the project owners and is the president of Tramway Engineering, a
consulting firm specializing in ropeways.




                                                                                     Page – 15.9
Do I Need A Rocket Scientist


        Michael Clotman
      Lift Maintenance Manager
        Angel Fire Resort, NM




                                 Page – 16.1   1
Abstract:



                                    Do I Need A Rocket Scientist
                                              Michael Clotman 1


The level of technology, and with it increased safety categories, has been impressive over the last
few years. However, it seems with every increase in technology comes increased fragility. PLCs
and PCs are very particular about their environment. Combining CPUs with lift systems is like
hooking your computer to a giant antenna.
Thanks to all these electronics, lift problems are becoming more complex. While ten lifts may
function perfectly, though, there are occasionally installations that will experience problems due
to their environment.
Angel Fire ski area in New Mexico has one such lift. It encountered numerous shutdowns and
electrical issues, and we couldn’t seem to eliminate them. We basically had to start over from the
ground up when investigating the sources of our problems.
The problems we were having with this lift came to a head in 2000-2001 ski season. We
discovered this also coincided with one of the worst years in recent history for sunspots and solar
storms. We discovered that two aspects of this lift were contributing to the electronic nightmare:
with its length, nearly two miles long, and its orientation, along a perfect east-west axis, the lift
was acting as a giant catch net for any solar winds that pushed geomagnetic storms down from
magnetic north.
Then we looked at other environmental factors that might effect the lift. There were induced
voltages on the haul rope from a power line that ran parallel to the lift. The towers themselves
were acting as antennae, picking up radio communications from 100 miles away. The power
quality we were getting was not the cleanest.
Ultimately, though, it was the Angel Fire Lift Maintenance and electrical department that had to
sort through all the data and come up with solutions. And these proved to be as complex as the
problems.




1
    Lift Maintenance Manager, Angel Fire Resort, NM


2                Page – 16.2
                                   Do I Need A Rocket Scientist?
                                              Michael Clotman 1


“Do I need to hire a rocket scientist?” I thought to myself while running correlations between lift
faults and sunstorm activity.*

The level of technology, and with it increased safety categories, has been impressive over the last
few years. However, it seems with every increase in technology comes increased fragility. PLCs
and PCs are very particular about their environment. Combining CPUs with lift systems is like
hooking your computer to a giant antenna.

Thanks to all these electronics, lift problems are becoming more complex. While ten lifts may
function perfectly, though, there are occasionally installations that will experience problems due
to their environment.

Angel Fire ski area in New Mexico has one such lift. It encountered numerous shutdowns and
electrical issues, and we couldn’t seem to eliminate them. We basically had to start over from the
ground up when investigating the sources of our problems.

The problems we were having with this lift came to a head in 2000-2001 ski season. We
discovered this also coincided with one of the worst years in recent history for sunspots and solar
storms. We discovered that two aspects of this lift were contributing to the electronic nightmare:
with its length, nearly two miles long, and its orientation, along a perfect east-west axis, the lift
was acting as a giant catch net for any solar winds that pushed geomagnetic storms down from
magnetic north.

Then we looked at other environmental factors that might effect the lift. There were induced
voltages on the haul rope from a power line that ran parallel to the lift. The towers themselves
were acting as antennae, picking up radio communications from 100 miles away. The power
quality we were getting was not the cleanest.

In the summer, lightning was taking a large number of proximity switches along with I/O blocks
and fuses in the filter bank, and it was damaging our computer operating system, which became
corrupted due to the constant noise and power fluctuations.* There is a radio station transmitting
tower on one side of the drive, and the diesel APU would seek the radio frequency instead of the
magnetic pickup frequency, causing the lift to surge and droop.

Discovering the sources of these problems—and their solutions—required much research. We
consulted with people from diverse fields: power quality experts, grounding experts, surge
protection people, consultants who worked with NASA, lift specialists with years of experience
and radio communications professionals.*



1
    Lift Maintenance Manager, Angel Fire Resort, NM


                                                                         Page – 16.3               3
Ultimately, though, it was the Angel Fire Lift Maintenance and electrical department that had to
sort through all the data and come up with solutions. And these proved to be as complex as the
problems.

Exorcising the Demons

Starting from the ground up, we looked at grounding and bonding. We installed a ground loop
around the top and bottom terminals and bonded together through all the towers. This eliminated
any potential differences and gave all the noise we were picking up a place to go. This also
helped with the lightning in the summer.

Surge protectors and filters were put on all incoming power, including the power to the battery
chargers for the control circuits. We also put protection at the end of our power rails on the
towers. The power line was buried, and the top one third diverted away from the lift. We went
through all bonding and tried to equalize all potential differences. A new operating system was
installed that did not require top to bottom I/O links.* We also installed Franklin rods on all the
towers to divert lightning away from the proximity switches.

We discovered that the haul rope needed to be grounded at all times, especially in the summer
when trying to unload the lift with severe weather approaching. This was achieved by putting
grounding studs in the bullwheel at the return and grounding brushes at the drive.

The fix was not perfect, but lift downtime was dramatically reduced in both summer and winter.
We no longer lost proximity switches and other components due to lightning. We were also able
to reduce the weather window. Before we completed our fix, lightning 40 miles out would fault
the lift. Last summer a tower took a direct hit and the lift stopped—but reset immediately, with
no lost components. Our equipment was also protected when the local Power Company decided
to drop the power to both our quads this past winter, without notification. The same occurrence
two years before took out blower motors and other 480 VAC equipment. The faults on the
operating system were reduced to nuisance faults and did not cripple the lift.

Lessons of Experience

Our experience shows just how much lift maintenance has changed. Lift maintenance personnel
are now required to be acquainted with more than just mechanical systems. They must also know
electrical, electronics components, computer operating systems, PLC programs and
troubleshooting, power quality, grounding, bonding, and the effects of environmental factors on
lift systems. These environmental effects can be local, such as poor harmonics due to unfiltered
DC drives, or global, such as sunstorm activity.

And so the answer to the question posed back in the beginning is yes, for at least one resort we
know of. Taos Ski Valley in New Mexico has an electrician so well versed in multiple
disciplines that they did, in fact, hire a rocket scientist to apprentice with him. The resort
management reasoned that only a rocket scientist would be able to replace head electrician Dan
Craybill when he eventually decides to retire. Simply hiring another electrician—even a very
good one—would not cut the mustard.



4            Page – 16.4
The answers to modern lift problems are not cut and dried. They require eliminating as many
detrimental factors as possible and taking a broad overview of the problem. Lift maintenance
personnel can not let themselves get tunnel vision.

Ultimately we cannot put ski lifts into a Faraday cage isolating them from their environment. The
lift industry needs to begin to look at lift-specific environmental technologies. This will be a hard
task, since most lift technology comes off the shelf from technologies that fit a wide range of
applications. But we must find ways to adapt them for our purposes, and our extraordinary
environment.

1. Space Environment Center-http://sec.noaa.gov for real time space weather, alerts and
   forecasts.
2. MTI surge protection, Power QC power quality and grounding, Decker communications
   radio and other telecommunications. Leitner-Poma Mikel Carhart extensive lift professional.
3. Leitner-Poma operating system courtesy Mikel Carhart
4. Conversation with Dan Craybill Rocky Mountain Lift conference 2002




                                                                         Page – 16.5               5
Lightning and Methods of Protection


          Stephanie Woodbury
               President
             Power QC, Inc.




                               Page – 17.1
Abstract:



                        Lightning and Methods of Protection
                                    Stephanie Woodbury


The importance of proper electrical site protection, including grounding theory, testing and
design, different methods for earth grounding.




            Page – 17.2

				
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