Pig Detectors

Pig Detectors are devices with an indicator to detect the passage of a pig in the pipeline during a pig run. They can be classified into two groups: intrusive and non-intrusive.

Intrusive Type

Permanently mounted to pipe via fitting (thread-o-let or flange mounting). Can be used with any type of pig with no special accessories. Usually consists of a probe that protrudes into the pipe and is mechanically triggered when the pig passes.

Non-Intrusive Type

Does not require permanent mounting. Usually attached to the pipe via a fiberglass saddle, strap, or other banding method. The pig must be equipped with a magnet (or other accessory) for sensor detection.

Typical Placement

Pig detectors are usually located near the launcher and receiver to confirm successful launch and receipt of pigs, or at any trouble area of the pipeline such as at a tee, elbow, or wye. They can be equipped with electrical switches and connected to a PLC to operate piping equipment such as pumps, compressors, valves, and mixing tanks.