In 2006 a new Pump Station was being built on Vail Mountain, to provide domestic water to several facilities on the mountain. Domestic water would be pumped through a short, very complex and very constrained pipeline, to a transition point in a steel pipeline supporting domestic water systems. Vail Resorts (VR) was interested in the VRS®-T Ductile Iron (DI) system, because it was being installed at Buttermilk and Steamboat in 2006. In early September, VR ordered the VRS®-T DI pipe/fittings required to complete this installation. Installation was completed and operating October 23, 2006.
VR was building a new domestic water Pump Station on Vail Mountain during the 2006 construction season. This project required a new domestic water line from the Pump Station to a transition point in an existing steel water line. This new transfer line would be short, but complex for several reasons: physical constraints caused by fixed transition points at both ends of the pipeline; constraints required to minimize the amount of pipe crossing service roads and installed under parking areas; and, short timelines required, because different sections of the new pipe system would have to integrate with other construction by other contractors. The foregoing constraints would require a larger number of fittings, which would increase the need for cutting/clamping ring procedures. In addition to the foregoing challenges, soils throughout this region were wet and moderately corrosive.
For the foregoing reasons, and because of similar problems with steel pipe in other areas, VR preferred not to use steel pipe in this application. VR investigated alternative pipe systems that might provide a better longevity than steel pipe. A major factor affecting this search was the fact that, during the 2006 construction period, DI pipe systems were being installed at Buttermilk Mountain and Steamboat Resort. For this reason, management at VR discussed this new DI system with technical and management personnel at both resorts, and in early September VR made the decision to use this new DI system. VR placed an order for the VRS®-T DI pipe and fittings required to complete this installation. The Installation was completed, and fully operational October 23, 2006.
Find a piping system that: would satisfy the pressures required for the pipe sizes in this system; would improve the longevity of the pipe system compared with steel pipe; could be installed easily and quickly; would provide a broad selection of fittings, and system flexibility, to deal with constraints caused by fixed transition points at both ends of the system, and the need to avoid service roads and parking areas; and, would minimize environmental damage throughout the project region. More specifically:
Operating pressures in this section of the domestic water line are 500 psig, with surge pressures up to 650 psig.
Corrosion of any material is based on the corrosivity of the environment surrounding the material. Steel snowmaking pipe in normal alpine environments has a longevity ranging from 20 to 35 years, depending on the corrosivity of the soil. In this region the soils were wet, and corrosivity levels were higher than normal. These conditions had to be dealt with. Other materials are available that will provide superior longevity than steel.
Initially, because of the late decision to move forward with this project, short timelines would have to be met. In addition, it would be necessary to have sections of this pipe system assembled and ready for installation, to be coordinated with other work by other contractors, making project coordination very critical by all parties. This ability to assemble pipe easily, quickly, and on short notice, would require short timelines.
The new transfer line would have physical constraints caused by fixed transition points at both ends of the pipeline; and, by the need to minimize the amount of pipe installed under service roads and parking areas. Both constraints would require the use of a larger number of fittings, and the need to complete more pipe cutting/clamping ring procedures than normal. Constraints that must be dealt with.
Stray Current Systems:
There will be utility systems close to the new Pump Station. These systems could create stray current conditions in soils in which the new pipe would be installed. These conditions should be dealt with.
A primary goal with all pipe installations in all alpine regions is to select/use materials which protect ecosystems, and maximize the integrity and sustainability of the natural resources. Ductile Iron (DI) materials from TRM have unique characteristics, not available with other pipe systems, including:
- DI pipe is produced using +98% recyclable materials.
- Joint design requires no welding or open flames at any time during assembly/installation.
- Joint design requires much less force to assemble; and, much smaller/lighter construction equipment to complete installation.
- Easier assembly and smaller/lighter construction equipment makes it possible to: complete installation using a much smaller construction footprint, reducing cleanup requirements; and, makes it possible to complete assembly/installation in much shorter timelines, providing much longer periods for terrain clean-up and restoration.
- Joint design requires much less force to assemble; and, smaller/lighter construction equipment for installation.
- Easier assembly and smaller/lighter construction equipment make it possible to: complete assembly/installation in much shorter timelines, providing much longer periods for terrain clean-up and restoration.
Based on previous field experience and problems with steel pipe systems, VR preferred not to use steel pipe in this application. For this reason, VR investigated alternative pipe systems that might provide a better longevity than steel pipe. A major factor affecting this search was the fact that DI pipe systems currently were being installed at Buttermilk Mountain and Steamboat Resort in 2006, and a major reason that this DI pipe was being used by others was the superior longevity of these DI materials. Management at VR discussed this new DI system with technical and management personnel at both resorts, and in early September VR made the decision to use the VRS®-T lock restraint DI system from TRM.
Advantages of the VRS®-T System:
- The joint design is special for this system, to allow the large diameter pipe (DN600) to support the operating and surge (400/550 psig) pressures in this system. In smaller diameters, normal operating pressures are 25 bar to 100 bar.
- The corrosion rate of steel is +3 times faster than the rate for DI; making the
longevity of the VRS®-T pipe +3 times greater than the longevity of steel pipe.
- The DUPLEX coating on all pipe provides active and passive corrosion protection, and a unique sacrificial repair mechanism for any pipe damage exposing bare metal. These characteristics extend the longevity of this pipe even more.
- The VRS®-T joint requires ±38% less force to assemble each joint; and, with the soft flexible gasket used in this joint, alignment of the pipe is not as critical, reducing the assembly time for each joint. Both issues make it easier, faster and less costly to assemble/install this pipe system in shorter timelines.
- The DI system from TRM provides a wide range of fittings in all pipe sizes, and provides easy cutting/clamping ring procedures. Both features were important because it would be necessary to have sections of this pipe system assembled and ready for installation, before other contractors could backfill foundations and complete pouring the concrete floor in the Pump Station. Photos below provide examples of these conditions.
- Because of short timelines needed to coordinate pipeline installation with other construction work, and because of fixed transition points at both ends of the pipeline; this installation would require a larger number of fittings than normally required for this size system. This would increase the need for cutting/clamping ring procedures. Photos below show some examples of these clamping ring joints.
- In addition to the broad range of different fittings in all pipe sizes in the TRM system, each VRS®-T joint has angular deflection, providing more flexibility in the assembly process. Both features make it easier to deal with utility system constraints in regions close to the new Pump Station, and efforts to minimize the amount of pipe installed under service roads and parking areas. To install steel pipes through this region it would have been necessary to cut/mitre/weld extensively. DI joint flexibility eliminated this. The photos below show how the parts availability and greater flexibility of this DI system was valuable.
- The VRS®-T joint requires smaller lighter construction equipment; and, a smaller construction footprint to complete the entire project in a much shorter timeline. This shorter construction timeline provided more time for site cleanup and restoration; considered to be an important environmental benefit.
Project Team Members:
CLIENT: Vail Resorts, Inc.
DESIGN: Vail Mountain Master Plan
DIP DESIGN/SALES/FIELD SERVICES: PNP Supply LLC
CONTRACTOR: In-house Personnel