Continuous polyurethane foaming process for production of tubular or tunnel like construction members involves casting foam components into a shell-like frame forming a moving reaction chamber

摘要

A filled polyurethane rigid foam system is injected by a mixing and metering head into the shell-like frame which acts as a reaction chamber and is open at the front end. The foam components react in the chamber and become rigid allowing the chamber to be moved progressively forward to produce a continuous construction.