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

November 2019 – 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.  Read more …

SIGMA's 54" Wedge Action Restraint is Put to the Test

SIGMA’s Engineering Team Devises a Solution to a Common Waterworks Infrastructure Problem: Aging Pipes 

In August 2019, SIGMA Corporation was invited by a large southeast wholesale Water Authority to put SIGMA’s 54″ Wedge Action Restraint for ductile iron through a stringent technical test. SIGMA hosted five prominent members from the Water Authority at SIGMA’s headquarters to devise a restrained joint solution for their in-ground 54″ ductile iron pipe, which had been manufactured to an outside diameter (OD) that had a different dimension to today’s industry standard OD. SIGMA’s Engineering Department for restrained joint products, headed by Satheesh Chandrasekaran, carefully investigated the situation and came up with a novel solution for the Water Authority using the existing products which included the restraint, gasket & sleeve to join both diameter pipes.  Read more …

SIGMA Focus on Waterworks Accessories

SIGMA Corporation is a major supplier of accessories to the waterworks industry. Today we are pleased to highlight our MJ T-Bolts.

Our T-Bolts are manufactured by the only domestic manufacturer of T-Bolts in the U.S., Birmingham Fasteners, who are a long-standing supplier to SIGMA.  SIGMA carries T-Bolts in a variety of materials and finished coatings. These T-Bolts exceed ANSI/AWWA industry standards and if required can be custom-coated or designed to fit your specific waterworks application.  SIGMA currently provides T-Bolts in the following materials:

- SS304 Stainless

- SS316 Stainless

- Flurocarbon-coated

- Cadmium

- Galvanized

- Cor-Blue (Cor-Blue is a registered trademark of Birmingham Fasteners. Genuine Cor-Blue T-Bolts begin with raw material that is then formed into high-quality T-heads, which are then finished with Fluorokote #1.)

For further information, contact your local SIGMA sales representative, or you can access our Accessories Product Catalog on our website.


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