Rebar Coupler Specifications

Rebar coupler Specification:

Rebar couplers can be used in construction by Roll thread Method Or By Cold Forging system Method.

Roll Thread Method:

In Roll thread system ,Single thread machine Required to make threads on Rebar directly by pressing TMT bars by using Thread Rolllers.

Three Thread Rollers are used in Machine to make roll thread on rebar.

This kind of system Can be used for small buildings like upto 20 storey tower .

COLD Forging Sytem of Rebar coupler:

In cold forging type of system Forging machine is required to forge TMT bar i.e to to increase Outer diameter to Maintain cross section area.

AS per ACI 318 and IS 1786 standard tensile strength of Rebar should of 1.25 times of Capcity.

Suppose we are using FE 500,then tensile strenth in pull up test shoud be 625 MPA or More,then only we can say coupler is passed.i.e Bar break

Normally for small diameter bars like 16 mm,20 mm,25mm,rebar Roll threads system can be used because there is no huge difference in cross section area,but 32 mm and above its recomenede to use COLD Forging system for better strength.


Standard of Rebar couplers:
Standard used as per international for Rebar coupler-ACI 318
India standard of Rebar coupler-IS 1786

Standard Sizes of rebar coupler:

16mm Roll thread Rebar coupler M16 x2 mm Pitch
20 mm Roll thread Rebar coupler M20x2.5 mm Pitch
25 mm Roll thread rebar coupler M25 x 3 mm Pitch
32 mm Roll thread rebar coupler M32x 3 mm Pitch
40 mm Roll threadRebar coupler M40x3.5 mm Pitch

Cold forging rebar coupler specification:

16 mm Cold forged Rebar coupler M18x2mm Pich
20 mm Cold forged Rebar Coupler M23x2.5 mm Pitch
25 mm Cold Forged Rebar coupler M29x3.5 mm Pitch
32 mm Cold forged Rebar coupler M36x4 mm Pitch
40 mm Cold forged Rebar coupler M44x4 mm Pitch