Stopping Machines for Pipeline Hot Tap Applications

Schallert's folding head and pivoting head linestop machines cover an extensive range from 8 inches up to 84 inches in diameter. Individual folding heads are sized for specific pipe-to-valve combinations, such as the FH0806 for 8-inch lines through a 6-inch valve, or the FH7248 for 72-84 inch lines through a 48-inch valve.

Folding head machines insert through a reduced branch fitting and unfold to seal larger pipe diameters, saving on valve and fitting costs. Pivoting head machines are a size-on-size solution rated for higher pressures and temperatures (up to 450 psi at 250°F), making them ideal for hazardous gases and chemicals in mills and refineries.

Pressure ratings vary by model and component. Standard folding heads are rated up to 150-250 psi, while pivoting heads handle up to 450 psi at 250°F. Jackscrew actuators and completion plug setters are rated up to 350-500 psi, allowing the overall system to be matched to the specific pipeline's operating pressure.

Yes, select models such as the FH7248 Folding Head and FH1612 are available for both purchase and rental. Rental is a practical option for one-off or infrequent line stopping jobs, while purchase suits companies performing regular pipeline maintenance and repair work.

A full line stop operation typically requires a folding or pivoting head, a compatible housing, a jackscrew actuator to drive the head into position, a completion plug setter to finish the job, and line stop flanges or fittings for pipe access. Schallert manufactures all of these components to work together as a complete system.

Jackscrew actuators drive the folding or pivoting head into the pipeline through the housing until it fully seals the line. They feature a chrome bar with etched stroke measurements viewable through a porthole, and are available with manual handwheels or remote chain/gear reduction drives for stroke lengths from 48 to 192 inches depending on pipe size.