Long Term Repair of Aged CSPE
Written by Andrew Mills | Product Manager; Special Projects
CSPE, also known as Hypalon has been in use as a floating cover and roofing material for over 40 years. One of the key features of CSPE is the ability to make repairs throughout the life of the material. Following proper procedures, repairs can be made with CSPE liners and floating covers in use for over 30 years.
The polymer used to make CSPE (Chlorosulphonated polyethylene) is a rubber. When manufactured the polymer is a thermoplastic but then cures over time to create what is called a thermoset type of rubber. Most rubbers are cured during manufacture but CSPE is made so that it doesn’t cure immediately. This thermoplastic stage gives us the opportunity to weld the CSPE together during fabrication and installation. Then the polymer cures which makes the material more flexible, stronger, more UV resistant, and more chemically resistant.
The curing of CSPE starts on the surface and works its way into the interior. When repairing CSPE that has been installed for a short period of time (up to 5 years) it may be possible to re-activate the surface so that welding can take place. Wiping the surface with a solvent such as xylene can often re-activate the surface for welding. Your installer can do a test to determine if the surface can be re-activated.
But the key attribute for CSPE repair is its ability to be adhesively bonded. Rubbers are regularly adhesively bonded and the joints produced are reliable and durable. Adhesive bonding of CSPE can be done at any time during its service life and the adhesive repairs will last for the life of the substrate.
A good example of repair of an aged CSPE floating cover is the Hinkle Reservoir in Folsom California. The CSPE (Hypalon) floating cover was installed in 1979 and is still in service 40 years later. In 2002 a section of the cover around an outlet valve was replaced. That repair was done on 23 year old material and has held up perfectly for the past 17 years. Additional minor repairs were completed at the 37 year life of the material with the material continuing to perform well.
Repairs of aged CSPE are easily accomplished using welding or adhesive techniques depending on the state of cure of the material. Detailed repair instructions and adhesive are also available. Your floating cover installation specialist can provide repair assistance for the best results. Contact your nearest Layfield office for further information.
To learn more about CSPE, click here. As well, be sure to check out this Layfield Technical paper on "CSPE Performance & History in Long Term Potable Water Storage Applications" presented at the 2019 Geosynthetics show in Houston, Texas. Click here to Read.