Spray in Place Pipe (SIPP): Materials Composite and Implementation Methodology for Surviving Pressure Pipe Failure

Abstract

Major advancements have been made utilizing spray in place pipe (SIPP) renewal technologies for both pressure and non-pressure pipe applications. For pressure pipe, current systems have been developed for non-structural, and semi-structural linings only. This paper will describe the development of a fully structural SIPP technology for pressure pipe applications including but not limited to potable water systems capable of meeting NSF 61 requirements. SIPP technology has several benefits such as same-day return to service, effortless service reinstatement, reduced environmental footprint, economy, market versatility, and minimized community impact. Conversely, the mechanical and control deficiencies of SIPP lining systems preclude current processes from yielding structurally independent linings in pressure pipe systems: Traditional SIPP lining materials have low creep resistance; adhesion between host pipe and lining can cause fracture of the lining during pipe failure events; both radial and longitudinal shrinkage of thermosetting materials will create an annular space between the lining and pipe. This annulus will result in hydraulic failures when fluid infiltrates behind the liner system at discontinuities. This study will explain in detail how the robotic and concurrent application of a closed cell porous elastomer, helically wound carbon fiber filament, and high-tensile strength rigid polymer will result in a composite system to create structurally independent linings. This paper will explain how this lining system can meet the requirements to be able to span perforations, cracks, and other discontinuities in host pipe to provide hoop strength and resistance to buckling forces.