Bautech International

Technical Data

METHOD OF STATEMENT FOR THREADING COUPLER

VIII. Tapping Machine (Threading machine)

The newly-designed tapping machine is the corollary equipment for machining the external screw-thread of end of steel bar. In general, the external screw-thread is machined with stationary tool when the workpiece rotates.

However, since the architecture steel bar has heavy weight and is longer in length. It is impossible for the workpiece to be fixed in power unit for machining. For this reason, it is necessary to research and design a special machine tool to solve the machining problem.

The tapping machine used for machining the straight thread of steel bar end has been successfully designed and manufactured in our factory. It is composed of machine bed, gear reducer. holding device, rotation-cutting-head, on-off regulator, coupling bracket, spline transmission, tool retract device, feeding unit, cooling unit and automatic control device.

IX. Advantages and Characteristics of Tapping Machine

The end of steel bar is clamped in the gripping mechanism of machine. The tool is fixed in the cutter head of power unit. As the power unit rotates and the tool device feeds, the end of steel bar shall be tapped with its feeding.

Having the advantages of simple structure, small volume and light weight, easy operation, high efficiency and low cost as well as reliable quality because of electrical control in whole process, it is suitable for actual condition in the architecture industry and enjoys high prestige among users.

It can tap the 60o UNC screws with M16 ~ 45, pitch 2, 2.5, 3, 3.5,and 4.

It is particularly suitable for machining of large workpiece, extra-long workpiece and the steel bar which can not rotate by itself. With two pairs of meshing gears, it drives the lead-screw in rotation. It can feed automatically, thus reducing the labor intensity.

With the special design and manufacture, a group of rotating tools, by means of the reliable positioning device, is firmly fastened on the saddle, which is placed in square stand with equal edge. Relying on the interconnected slide slot and slide rail, they can open and close freely and control the size of thread end rationally.

X. Prerequisite for Threading in End

The upset end of steel bar must conform to the sizes shown in Table – 1;

The semi-finished product with the concentricity between end and steel bar < 0.3;

The semi-finished product with out-of-roundness of end, circumference <1/3, unfilled corner <3 x 1.5

The semi-finished product with loss of end (middle, root), circumference <1/3, unfilled corner 5 x 1

The semi-finished product with axial crack in end is unallowable.