GUIDELINES FOR USE

Trenchless Supplies Towing Heads are specifically designed to remain with the product pipe even under excessive loads. With this in mind, we ask you to adhere to the recommended towing instructions from the pipe manufacturer. 

The maximum recommended towing load for polyethylene pipe is 50% of the ultimate tensile strength of the pipe. The ultimate tensile strength can be defined as the load necessary to yield the polyethylene material. 

The pipe manufacturers’ recommendation assumes that the tensile loads are applied for less than one hour. In these situations it is recommended that a period of at least one hour should pass after full insertion is complete. This then allows for the viscoelastic recovery of the material. 

During techniques such as horizontal directional drilling, loads are applied for substantially longer than an hour, often exceeding 24 hours. It is recommended that for these longer installations maximum towing load should be rated to 40% of the ultimate tensile strength. The rest time to allow for the viscoelastic recovery should be at least equal to the time under load, ideally five times the period under load. 

Please refer to the relevant pipe manufacturer’s website for specific loads.