Heat shrink joints are designed for the reconstruction of the jacket pipe in the joint areas of the preinsulated Pipes. The joints made of radiation crosslinked polyethylene guarantee their high shrink strength and the shape memory. These features are basic for performing reliable, flexible and tight joint which is resistant to temperatures from -55°C to +125°C.

Radiation crosslinked heat shrink joints perfectly reconstruct the jacket of the preinsulated pipe which results in reducing the soil frictional resistance and thus the life length of the joint. They are also highly resistant to stress corrosion. Due to high shrinking strength, ageing resistance and mechanical strength against the soil stress as a result of the thermal elongation in the pipeline, the joints assure reliability and safety of the performed joint.

Random spatial network of hydrocarbon bonds appears in the entire structure of HDPE material exposed to radiation crosslinking process. The crosslinking process restricts the quantity of unbounded molecules in the volume of the material which excludes the fusion of two elements of crosslinked polyethylene. The foaming holes are the only areas in the heat shrink joint protected against the crosslinking during the production. The remaining part of the heat shrink joint is crosslinked. The non-crosslinked area keeps the initial features of HDPE which allows for welding the plugs.

This solution is registered and protected by patent No. PAT. 205918  

Specification and properties of joints

• ground load test certificate (“sand box” test or box test) for 1500 cycles in accordance with PN-EN 489: 2009, joint sealing with hot melt glue and butyl rubber compound,
• equipped with 2 vent plugs and 2 fusion plugs, cleaning wipes,
• factory-made filler holeswhich are adapted to the vent plugs,
• heat shrink joint is made of radiation cross-linked, black high density polyethylene,
• high mechanical strength of crosslinked material ensures resistance to tearing and abrasion,
• use of a suitable seal in the joint protects the joint area in difficult conditions,
• small number of construction elements of the joint reduces the assembly to a minimum time, and thus increases the assembly efficiency,
• heat shrink tapes are not required which reduce the cost of assembly,
• joints are resistant to corrosive chemical factors and UV radiation,
• a homogenous layer of sealant as a hot melt adhesive and / or butyl mass is not susceptible to sticking of foreign bodies and does not tear when the joint is moving on the casing pipe,
• each joint is individually packed in a white foil sleeve.

Long joints with the letter “L” (M_DPW-L) are available for connections with a bare end of 220

Content of the joint set

• Heat shrink joint radiation crosslinked with factory made holes
• 2 venting plugs
• 2 welding plugs
• 2 cleaning tissues
• Mounting instruction