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SIGMA is the only manufacturer to offer 3″-60″ Gland Replacement Wedge Action Restraints for PVC Pipes in North America

SIGMA Corporation is proud to introduce the One-Lok Model SLCE wedge action restraint for 42″ & 48″ PVC pressure piping. The new One-Lok has a unique design, which allows the product to act as both a pipe restraint and as a gasket compression gland. Additionally, the restraining glands have been designed to minimize the assembly time required to install the joint. This feature differs from competitors’ products, which require the use of an additional mechanical joint follower gland. As a further benefit to customers, the same restraining gland can be used for both mechanical fitting joints and bell harness PVC joint assemblies.

Features of the One-Lok Model SLCE wedge action restraint for 42″ & 48″ PVC pipes include:

  • Fewer wedges and break off bolts are required during installation (when compared to the number of T-Bolt holes). This feature greatly reduces the installation time required for proper joint assembly.
  • Additional extended lugs for the gasket bell OD, which can be used for bell harness PVC pipe joints.
  • Same wedge & break off bolt for 42″ & 48″ sizes, which will provide interchangeability between these sizes.
  • Internally tested, approved and recommended on all classifications of 42″ and 48″ AWWA C900, including thin wall pipes.
  • Restrainer glands are supplied with Sigma CORR-SAFE e-coated for enhanced corrosion protection.
  • Supplied as a pack, which includes the standard T-bolts and nuts, as well as SIGMA’s enhanced sealing capability with the SigmaSeal mechanical joint gasket.
  • Product is available upon request with Stainless Steel or Fluorokote/Teflon T-bolts and nuts.

SIGMA remains the industry leader for North America in pipe joint restraint and with the launch of these restraint sizes, is the only manufacturer to offer a nominal size range of 3″ through 60″ gland replacement wedge action restraints for PVC pressure pipes. This unique design was made possible by Satheesh Chandrasekaran – Restraint Product Engineer comments Steve McDonald – Restraint Product Manager and we pride ourselves on designing, developing, manufacturing and supplying products that meet or exceed end-user expectations.

For any further information about the SIGMA Restraint Product Line contact Satheesh at or Steve McDonald at

Pipe Restraint Products – Canada

Pipe Restraint Products – Canada

SIGMA offers a wide range of both domestic and imported restraint products in PVC and ductile iron pipes. Our extensive product line includes ONE-LOK, PV-LOK, harness restraint. We stock products in 2-64 inch size ranges.


Ductile Iron Pipe Restraint
PVC Pipe Restraint
Additional Restraint Applications


SIGMA offers competitive pricing and added convenience on accessories like flange packs, gaskets, and bolts, and many other items, especially when ordered in conjunction with fittings and waterworks products.


HDPE Products

HDPE Products

SIGMA’s High Density Polyethylene (HDPE) Product Division offers an extensive range of thermo plastic water meter boxes, meter pits, extensions, and lids. Customs options are available. Made in USA.

Fabricated Products

Fabricated Products

SIGMA offers a complete line of products for Fabricator application, including threaded flanges for ductile iron, MJ threaded bells, ductile iron & cast iron filler flanges, anchor flanges and wall collars.

SIGMA’s threaded flanges are manufactured with the high precision CNC machining process, which makes them unmatched for accuracy in today’s market.