Our Couplers produce a full strength joint yet they are among the smallest in the Kamar range, best suited to large scale projects requiring a high volume of couplers. The end of each bar to be joined is cut square and enlarged by cold forging. This increases the core diameter of the bar to ensure that the joint is stronger than the bar.
The threaded ends of the bars are protected by an external plastic cap (TPC). Couplers, which are usually supplied attached to the bar, have their internal threads protected by an internal plastic end cap (CPC). For certain applications, especially where the couplers system is being used in deep pours, the coupler end caps may not prevent the ingress of concrete fines. For these applications, further protection may be required. Couplers are also available to join bars of different diameters.
Parallel metric threads are cut on to the enlarged ends.
The threaded end can be proof tested to a force equal to the characteristic yield strength of the bar. A nominal allowance of +50mm per threaded bar end should be made for cutting square and cold forging.