Yes. In many mining and industrial applications, HDPE pipe has been installed above ground and has provided and continues to provide excellent service after 15 to 25 years (North America), with the potential to remain in service for many more years.

The upper limit temperature for pressure service is 140 degrees F. In structural pipe, gravity flow applications in stable soils; the upper thermal limit is considered to be in the range of 160F for long-term exposure; and up to 180 F for short-term intermittent exposure. The low temperature limit is usually regarded as minus 130 degrees F (see next question). Cold temperatures do not adversely affect HDPE in static applications. Water within the pipe may freeze solid without damaging the pipe.

KWH offers HDPE fittings in standard configurations, including: straight and reducing tees, elbows, crosses, concentric and eccentric reducers, flanges, mechanical-joint adaptors, outlet branch-saddles, etc. These can be fused directly to the HDPE pipe. Custom fittings are also available upon request.

Sclairpipe and WehoGas are available either in coils or straight lengths. Coils are normally available for small diameter pipe (6 inch and smaller). Weholite is manufactured only in straight lengths and it is available in custom lengths up to 60' long.

THE US EPA expects 100-year service life from HDPE landfill liners. Buried solid wall or profile wall HDPE pipe should last at least as long. HDPE pressure pipe was first used in water service over 50 years ago. Current accelerated testing methods predict that today's HDPE pressure pipes will last much longer than 50 years. Everything points to a service life of at least 100 years in a properly designed and installed HDPE pipe system.

Yes, HDPE pipe has a specific gravity of about 0.95 so it will float. For underwater, anchored pipeline installations, it is important to specify the proper weights and spacing of the weights. Screw-anchors are a practical alternative. Whenever possible, an underwater pipeline should be installed in a trench with protective crushed rock cover. (See KWH's 'Marine Installation" brochure and/or the Marine Installation chapter on PPI Handbook).

Yes! It is necessary to know the diameters to be connected and to define whether the pipes to be connected together have a socket or otherwise.

Unfortunately, most plumbing stores don't carry HDPE - often times the store employees have never even heard of it. Usually it can only be found at large industrial plumbing supply places. You can also purchased pre-cut, plugged pieces of HDPE pipe from Pyrogear.net, which specializes in making mortars for fireworks.

Definitive Sealing: by welding the Valsir sealing cover (art. 342). Non-definitive sealing: solution A: by welding the Valsir sealing cap (art. 340). Solution B: by welding the Valsir collar (art. 347) then, using the Valsir free flange (art. .45), the corresponding set of Valsir bolts (art. 341), the Valsir sealing gasket (art. 343) and the Valsir blind flange (art. 346).

If the proper amount of ultraviolet stabilizer has been added to the colored pipe resin, non-black pipe can last several years in outdoor storage. Non-black pipe is not recommended for permanent outdoor use. Black PE pipe has been stabilized with carbon black, which is the most effective ultraviolet stabilizer. PE pipe with carbon black UV stabilization (the normal black PE pipe), may be used indefinitely outdoors.

A No. All objects expand and contract. As with all materials, expansion and contraction must be taken into consideration when designing a HDPE piping system. The resistance to movement provided by friction between the pipe and its' embedment is usually sufficient to prevent thermal expansion and contraction. No. When HDPE pipe is buried, the temperature of the system becomes much more stable than when it was above ground. Therefore it will exhibit far less dimensional change.

Yes, HDPE pipe is suitable for direct burial under railroads with just 4-5 feet of cover. An engineering burial analysis is recommended. Due to the prior poor experience with "brittle" PVC (plastic) pipe, most railway specifications require that all pipe crossings must be encased in steel pipe. Based on a structural evaluation, impact tolerant HDPE pipe does not require a steel casing, but jurisdictional requirements will usually prevail.

HDPE pipe can be cold or hot (under pressure) tapped using saddle fusion tapping tees, electro-fusion tapping tees, Fuse-A-Corps, and branch-saddles which are readily available in the industry.

Most other companies sub-contract out their playset installations, whereas at King of Swings all installers are year-round, full-time employees. To successfully install playsets in-ground, a learning curve or training period is necessary. Companies that sub-contract out their installations are not able to afford such a level of expertise. Furthermore, if redwood or cedar is the only type of wood offered, in-ground installation is simply not possible.

For non-pressure 'drainage' applications, flexible rubber couplings have been used for decades with success. These flexible couplings are made for joining all types of gravity flow drainage pipe, including transitions from one type or size of pipe to another. For pressure applications and low-pressure sewer applications, HDPE transition fittings, HDPE mechanical-joint adapters, Gasket-joint adaptors, HDPE flanges, and standard metal couplings with internal stiffeners are recommended.

The inside surface of HDPE is extremely smooth and has a very low long-term design coefficient of friction. The roughness co-efficient to use with Ductile Iron pipe recognizes the likelihood that the ID roughness will degrade over time. The smooth bore of HDPE pipe is maintained throughout its service life. It is often possible to use a polyethylene pipe with a smaller inside diameter than the comparably sized ductile iron pipe, and still achieve an equal or greater flow.

No. HDPE and PVC pipelines are installed using the same standard backfill procedures. Both are thermoplastic materials, requiring the same considerations for proper embedment and backfill. The popular ASTM standard D2321 applies to both pipe materials.

For Sclairpipe and WehoGas the rule of thumb is to use a minimum bending radius of 50 times the nominal diameter of the pipe. Weholite can be bent to a minimum bending radius of 200 times the nominal diameter.

UNI EN 1519-1 standards indicate 95°C, whereas the softening point, namely the temperature which causes the piece to deform corresponds to 125°C. Therefore, even temperature peaks exceeding 95°C do not create problems.

The CSA standard allows only high-density polyethylene pipe, with the three most common diameters being 0.75", 1.0" and 1.25". Sections of pipe are heat fused and many suppliers offer a warranty of 25 years. The resin in this pipe is the same used in the pipe used to transport natural gas. This plastic does not degrade under sunlight and is warranteed not to fail. Most units include all pumps and controls, but it may be the responsibility of the contract to obtain some individual components.