Rotomolded containment fitting and method of use

An fluid inlet/outlet fitting assembly for vessels having leak containment shells with inner and outer vessel walls defining a space there between comprising:

• a) a first pipe flange and a second pipe flange;
• b) an elongated tubular member attached at one end to said first pipe flange, and
• c) a molded flexible boot having both a first and a second external flange portion said boot surrounding said tubular member with said first flange portion secured to said second pipe flange, said second flange portion of said boot is connected to an outer surface of said outer vessel wall;
• with
• said second pipe flange being attached to an end of said tubular member opposite said first pipe flange, said second pipe flange further comprising a threaded pipe connection means located adjacent said tubular member for attaching external pipe.

A method of compensating for expansion and contraction of double wall polyolefin vessels having an inner vessel surrounded by an outer vessel with a space between the vessel walls, relative to an inlet/outlet fitting assembly, a portion of which is connected to said inner vessel and passes through a wall of said outer vessel comprising the steps of:

• providing an inlet/outlet fitting assembly comprising:
• i) a first pipe flange;
• ii) a flexible boot having first and second flange portions and at least one corrugation portion, said first flange portion secured to said first pipe flange;
• iii) an elongated tubular member attached to said first pipe flange and passes axially through said flexible boot;
• and
• iv) a second pipe flange secured to an end of said tubular member opposite said first pipe flange;
• b) attaching said second pipe flange externally to a wall of said inner vessel;
• c) aligning said second pipe flange with an aperture located in the wall of said outer vessel,
• d) passing said elongated tubular member through said aperture and connecting one end of said elongated tubular member to said second pipe flange;
• e) attaching the second flange portion of said flexible boot externally to the wall of said outer vessel in a manner whereby said elongated tubular member is centrally located and extends from said second pipe flange longitudinally through said flexible boot;
• and
• f) attaching said first pipe flange to said first flange portion of said flexible boot in a manner whereby an end of said elongated tubular member opposite said second pipe flange is located within a socket portion of said first pipe flange.