Innovative Pipe Material Levels Up

Have you heard about the latest advancements in the large diameter pipe world? If not, here are two salient words you should be familiar with:

“QUIKJOINT” and “PUSH PIECE”

Now if these two words cause you to think of anything other than steel reinforced polyethylene pipe, then please take a moment to read on and discover how Contech’s DuroMaxx® SRPE pipe has recently leveled up the installation and air testing game for large diameter pipe applications. The design of large conveyance pipes for systems such as gravity sanitary trunklines, storm sewer mains, low pressure irrigation, raw water transfer, and flood mitigation, have several important aspects to consider*:

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DuroMaxx® SRPE pipe (ASTM F2562) was first introduced to North America by Contech in 2008 as a technology that excels at each of the above pipe criteria:

1. Size Range: SRPE diameters start at 30” and go all the way up to 120”.
2. Hydraulics: Smooth interior surface provides a Manning’s n coefficient of 0.012.
3. Strength: Structural integrity is provided by high-yield 80ksi steel ribs which ensure there is no creep or deformation of the plastic over time.
4. Cost: SRPE is very competitive with other large watertight pipe materials, such as RCP, fiberglass, and unreinforced plastics.
5. Service Life: Hydrostatic Design Basis stress rated resin (345464C per ASTM D3350) will meet a 100-year design service life for most wastewater and storm applications. 
   
   However, the two remaining key design criteria from above, installation and joints, are where Contech has made recent innovative advancements:
   
   
6. Installation: Homing smaller diameters (30” through 48”) is typically accomplished in the field by using a nylon sling or choke-strap to simply bring the gasketed pipe spigot into the bell housing. However, the homing of larger sizes, 54” through 120”, can be quite cumbersome. To provide a more efficient field homing process for these larger diameters of SRPE pipe, Contech has developed a “Push Piece” consisting of a ring of SRPE pipe material with steel cross members and extension arms which can be inserted into the pipe. This allows the installer to apply direct longitudinal force with the excavator to push the joint home quickly and efficiently for a positive seal. It also has a connection for internal cable pulling, if desired.
   
   
   
   
7. Joints: Contech has developed a substantially robust bell & spigot joint called QuikJoint®, which not only provides high strength encapsulated steel reinforcement to maintain compression on both sides of the dual sanitary gaskets but also allows for an innovative and efficient method of confirming joint tightness throughout the diameter range.
   For pipe systems that require post installation testing to verify water tightness, the current industry methods can be expensive, time consuming, and cumbersome – especially for diameters above 30”. Some of these methods are listed below:

1. 1. Low pressure air testing (ex: ASTM F1417) - using pressurized plugs at the pipe ends can be a safety concern, especially with larger sizes.
      
   2. Hydrostatic leakdown test (ex: ASTM C969) – this test requires a considerable source of water, time for the pipe system to acclimate, and then the fun begins with trying to locate the leak.
   3. Joint isolation test (ex: ASTM C1103) – this rare test involves sourcing large mechanical bladders which must be lowered down and assembled in the pipe, pushed into position in order to isolate a single joint and tested.
   4. Visual inspection – this agricultural approach may be acceptable for large sizes where the above methods are either too time consuming, expensive, or just not available.

This is where Contech’s QuikJoint® can help to provide a fast, efficient, and cost-effective way to facilitate post installation joint testing of large diameter DuroMaxx® SRPE pipe. This clever method allows the annulus space between the two gaskets to be subjected to an in-field low pressure air test. A single technician can usually perform this test in less than two minutes using basic equipment including a small air compressor, cordless drill, 1/16” NPT tap, and pressure gauge.

Once the test is completed, the small tap can be removed and plugged. In the event of a non-definitive test, the gasket annulus can be fully sealed with an injectable hydrophilic joint resin.

Below is a quick video of this joint test method being performed inside an installed 78” DuroMaxx® SRPE pipe.

Take your next large diameter pipe design to Boss Level with DuroMaxx® SRPE and the new QuikJoint®.