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Sight Glasses Provide Leak Monitoring in Dual Containment Piping System

Beneficial for Liquid & Gas Pipelines

Cedar Grove, New Jersey & Odessa, Texas — To satisfy a need for visual monitoring of leakage in dual containment systems, a petroleum plant has installed a series of Plast-O-Matic’s “sight glasses” in its diesel fuel piping. The devices, which are simpler and less expensive than other monitoring methods, provide instant visual confirmation of a leak in the primary pipeline.

The Sight Glasses are installed on 1/2″ connections at key points in the bottom of the outer containment pipe. In the event of a leak, the fuel will collect at the lowest point–the sight glass–and raise a day-glo float in the chamber. As the brightly colored float rises above a blackened portion of the sight glass, it creates instantly recognizable visual confirmation of the problem.

Constructed of corrosion-resistant Pyrex® on the inside wall and high-impact acrylic on the outside, the Plast-O-Matic sight glass meets the need for for dual containment throughout the system. O-rings allow the indicators to seal at low pressure as well as high pressure, an attractive feature for dual containment systems. A full 360° viewing area in the sight glass permits inspection from anywhere near the piping.

Useful in Many Applications

Plast-O-Matic’s sight glasses are designed to give instantaneous visual confirmation of pipeline flow. In another application, the sight glass is installed directly in a soil remediation system, where streamers within the chamber flutter when flow is present. It is also frequently used to visually confirm the presence of a process additive; in these cases the sight glass is installed downstream of an injection system. The sight glass is surprisingly rugged, and is available in pipe sizes from 1/2″ to 8″ NPT. Standard O-ring seals are of Viton or Buna-N.

The sight glasses, from Plast-O-Matic’s True-Blue line, are manufactured with PVC, Corzan® CPVC, Polypropylene, Kynar® PVDF or PTFE ends. Please click here for complete details.