Abstract: A method and apparatus for making a welded thermoplastic polymer article are provided. The method includes the application of a vacuum combined with sufficient heat to make the polymer flowable. The method and apparatus are especially well-suited for welding thermoplastic polymer sheets to the interior of process vessels. The resulting article has improved qualities over articles which are welded by other methods.

Abstract: Nozzle repair shields and methods for installing them are provided by this invention. The nozzle repair shield includes a cylindrical body portion having an annular flange disposed from the top end and at least one sealing lip disposed at its lower end. The body portion further includes an annular support band located in its lower end for supporting the sealing lip during insertion and use. The preferred shield is constructed from machined PTFE stock, and further includes resilient spacing members between the sealing lips to further reduce damage to the sealing lips and subsequent loss of a fluid-tight seal.