Line Stopping Explained

Indoor Line Stops are typically performed on steel, copper or stainless lines containing chilled/heated water, domestic cold/hot water, air, gas & cooling water etc. Underground Line Stops are typically performed on Cast Iron, Ductile, C-900 PVC, ACP, HDPE, Prestressed/Pretensioned Concrete, CLMC, PCCP, and steel pipe.

The Line Stop creates a temporary control point that can be removed after modifications or valve replacements have been made. After the hot tap is made, a line stop machine is attached to the temporary valve, and the valve is opened.

The line stop is inserted into the line to seal on the pipe i.d.. After performing the necessary modifications or service repairs, the line stop is retracted, the temporary valve removed, an internal completion plug is installed inside of the flange on the line stop fitting, then a blind flange is installed as a secondary seal.

There are various types of line stop machines. The latest line stop technology is a reduced size folding head which enters the pipe through a reduced branch hot tap. Example: A 16″ folding head line stop is inserted through a 12″ valve and opens up to a full 16″ size in the pipe. Especially great for concerns of size on size taps. A pivot head line stop machine is typically used for steam and for pressures over 250 psi. A pivot head Line Stop requires a full size hot tap in order to be inserted.

Single line stops can be used to stop off a line for repairs. Two or more line stops can be used in tandem or separate to isolate one or several lines at once. Contents in the line can be bypassed around the line stops, leaving an isolated section to alter, repair, or add a valve, while service line stays in service.

Line Stop services can be performed on almost any kind of pipe, from 1/2″ – 84″ and larger sizes in some cases. Alternate to a Line Stop can be a Valve Insertion Serving: California, Nevada, Utah, Idaho, Arizona,Colorado, Montana, Wyoming, Nebraska, New Mexico and South East Texas.