Westlake Pipe & Fittings' Certa-Lok® self-restraining pipe system provides a restrained joint by utilizing precision-machined grooves on the pipe spigot and inside the pipe bell or coupling. When assembled, a spline is manually inserted or imbedded in the pipe bell, or coupling, engages a grove in the spigot resulting in a continuous circumferential restrained joint that locks the segments of pipe together.  A flexible elastomeric gasket located in a groove in the pipe bell, or coupling, provides a hydraulic pressure seal.

Certa-Lok® is available with a Restrained Joint (RJ) coupling or with a Restrained Joint Integral Bell (RJIB).

The advantages of the Certa-Lok joints are:

• Quick and easy joint installation
• Tensile strength in BOTH directions (PUSH and PULL), excluding CLIC
• Corrosion protection is not required
• Provides an a restraint system within the OD of the pipe system
• Eliminates the need for external restraints and thrust blocks (as applicable)