The concept of joining piping by bolting mechanical couplings onto it was developed nearly 75 years ago. Now, the grooved method is being used extensively as a cost-effective alternative to threaded, flanged, and welded systems for HVAC, plumbing, fire protection, industrial processes, mining, shipboard, and equipment manufacture. Also it is being used for hydraulic lubrication sysstems, water and wastewater treatment plants, oil field operations, power plants, and military applications.