Inflatable Elastomeric Plug For A Dual Containment Piping System

Abstract

An inflatable annular plug for use in creating a seal between an outer conduit and an inner conduit in a dual containment piping system comprises an annular structure for fitting into the piping system. A first connector is bonded to the plug for enabling the plug to be inflated by an external fluid source. A second connector extends through the plug in an axial direction for enabling fluid to flow through the plug and is bonded to the plug at both entrance and exit points. An outer surface of the plug is formed with a plurality of circumferential ribs and lands to form a plurality of axially spaced seals between the outer conduit and the plug. The plug is used in conjunction with a second plug to form a sealed test space between plugs.

Description

SPECIFIC DATA RELATED TO THE INVENTION [0001] This application claims the benefit of U.S. Provisional Application No. 60 / 692,616, filed Jun. 22, 2005.[0002] The present invention relates to dual containment pipe systems and, more particularly, to a method and apparatus for leak testing of annular spaces between inner and outer conduits in such systems. BACKGROUND OF THE INVENTION [0003] Dual containment pipe systems are utilized in applications in which leakage of a fluid would create undue danger or environmental damage. The systems include an inner pipe or conduit, sometimes referred to as a “carrier” pipe, for carrying a fluid and an outer pipe or conduit, sometimes referred to as a “containment” pipe, through which the inner pipe extends. By way of example, such systems may be used in chemical plants, landfill applications, in sewer systems or in petroleum product conduit systems. The dual containment system isolates and dual contains the effluent or the chemical product from it...

AI Technical Summary

Benefits of technology

[0006] The apparatus is used in pairs so as to isolate a section, i.e., a test space, of a dual containment system. A section may be short, such as measured in inches, if the testing is being conducted on a fitting, or a section may be measured in thousands of feet if the testing is being conducted on an extended length of pipe. In either case, each annular apparatus is inflated to an appropriate pressure such as, for example, between 35 and 80 pounds per square inch (PSI) to form a complete seal at each apparatus that isolates a section of the containment system to be tested. Other pressures may be used depending on the size of the conduit, the material of the conduit, the pressure requirements of the conduits and other characteristics of the inflatable apparatus. Thereafter, the annular test space defined by the apparatus and the inner and outer conduits is pressurized and monitored to detect any leakage. The test space may be pressurized with air or a selected gas or even a liquid depending on the particular conduit undergoing testing. The pressurizing fluid is preferably introduced through piping passing through at least one of the annular app

Problems solved by technology

Any leakage in the inner or outer conduit will result in a pressure drop in the monitored pressure.

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