During the November 
of 2014 several samples of reinforcement bars with diameter of 36 mm from 35GS steel were welded on the friction welding machine PST-20T which was designed and manufactured in KTIAM LLC. Tests showed that durability of joint exceeds the durability of the basic metal, and disruption of bars occurred on the significant distance from heat-affected zone. (Protocol №1549 from 06.11.14 of laboratory ООО PO«KSMI»).
The resulting joints can be graded according to GOST 14098-91 with 5 points – durability of basic metal and plastic disruption is guaranteed.
It is also important to admit that the joint’s cross-section after the flash removal becomes greater than the effective cross-section of the rebar, given that the metal in the cross-section has fine equiaxed structure with enlarged viscosity and durability.
Results of tests allow to apply friction welding in the upbuilding of the reinforcement bars, moreover, the restriction of 2 joints on the 9 meters of length is proven to be excessive. The number of joints can be increased to one on one meter of rebar without the harm for the rebar’s durability, which allows to avoid the wastes during the production of workpieces from the reinforcement bars, that can sometimes reach up to 35%.
