Why Pipe Warp Is NOT an Issue for SIGMA Restraints

Dennis Wilson, Technical Sales Coordinator, Answers Technical Questions from the Field

My PVC pipe is warping. Does this mean it is going to leak?” This is a relatively common concern for contractors, especially among those less familiar with SIGMA’s ONE-LOK restraints for PVC pipe such as our SLCE, or our newest product, the SLO. And we can see why you might be concerned. However, rest assured that when the products are installed properly, they won’t leak. They will perform as designed, delivering the quality seal and restraint you’ve grown to expect from SIGMA.

Once you’ve completed the “gland portion” of installation and tightened the T-Bolts and nuts to the recommended torque, activate the wedges utilizing our breakaway bolts. While tightening per the instructions and after completion, you might notice some “flattening” of the PVC pipe surface. (The fancy term for this is ovality.) This “flattening” often raises the question “Will it leak?”. The short answer is no; the innovative design prevents leakage. There is enough distance from the gasket to the wedge contact area to accommodate the ovality so that it doesn’t extend to the area where the gasket is sealing.

So, when choosing any of SIGMA’s superior restraints you can rest assured of excellent performance and peace of mind — as long as you install them as per our instructions.

For information about this or other SIGMA Pipe Restraint Products, please contact Dennis Wilson at dwilson@sigmaco.com or Satheesh Chandrasekaran at MCS@sigmaco.com