A water trap is a device that allows gas and air to pass but holds back water.
Pigtail Siphons
Industrial factories utilize steam as a pressurized fuel for energy consumption. This steam needs to be regulated by a gauge, but the gauge must have a way of being safe from the powerful heat and pressure of the steam itself. This is where pigtail siphons (or siphons) come in.
Function
Pigtail siphons are looped pipes filled with water that are placed in piping configurations directly before an instrument gauge, normally to measure steam pressure, in order to shield steam and possible surges from the gauge's sensitive mechanics.
Significance
The trapped water within the loop of the pigtail siphon stops super-heated steam vapor, and allows the heat to disperse through the water, rather than letting it pass and damage or destroy the gauge on the other end.
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The following photograph shows a pigtail siphon connected to a pressure gauge sensing pressure on a steam line:
Mounting Brackets An accessory designed for differential pressure transmitters, but useful for other field – mounted instruments. Such a bracket is manufactured from heavy-gauge sheet metal and equipped with a U-bolt designed to clamp around any 2 inch black iron pipe. Holes stamped in the bracket match mounting bolts on the capsule flanges of most common differential pressure transmitters, providing a mechanically stable means of attaching a differential pressure transmitter to a framework in a process area.
The following photographs show several different instruments mounted to pipe sections using these brackets:
Heated enclosures
In installations where the ambient temperature may become very cold, a protective measure against fluid freezing inside a pressure transmitter is to house the transmitter in an insulated, heated enclosure. The next photograph shows just such an enclosure with the