Radial drilling machine tapping can not be separated from the tap this tool, with the tap processing method called tapping, tap is a special tool for tapping. Tapping is to use a certain torque to screw the tap into the bottom hole to be drilled to process the internal thread. Bottom holes need to be drilled before operation tapping. Due to the tapping of the tap cutting edge in addition to the metal cutting effect, the workpiece material also produce extrusion effect. As a result of extrusion, the tap may be squeezed, resulting in chipping, breaking and disorderly buckling of the workpiece. Therefore, the diameter and depth of the thread bottom hole should be determined according to different materials to avoid damage to the tap.

Tapping skills and key points of radial drilling machine:

1) The orifice of the threaded bottom hole on the workpiece should be chamfered, and both ends of the through hole thread should be chamfered.

2) The position of the workpiece clamp should be correct, and the center line of the threaded hole should be placed in a horizontal or vertical position as far as possible, so that the tapping can easily judge whether the tap axis is perpendicular to the plane of the workpiece.

3) At the beginning of tapping, try to put the tap straight, then add pressure to the tap and turn the hand. When cutting into 1-2 turns, carefully check and correct the position of the tap. Generally, when cutting into 3-4 threads, the tap position should be correct. Later, only need to turn the hand, and should not add pressure to the tap, otherwise the thread shape will be damaged.

4) at the beginning of the tapping, every turn twist 1/2-1 turn, it should be reversed about 1/2 turn, so that the chip is easy to discharge after breaking, and can reduce the cutting edge due to sticky chip and the tap rolling phenomenon.

5) At the beginning of tapping, the radial drilling machine shall be reversed, the tap shall be inserted into the bottom hole of the thread, some vegetable oil or special tapping oil shall be applied to the tap with a brush, and then the main shaft of the rocker drill shall be rotated forward. During the tapping process, several reversals shall be made to break chips and prevent the tap from being cut off.

6) When tapping the screw holes of plastic materials, add lubricating coolant. For steel, the general use of oil or a larger concentration of the emulsion, the higher requirements of the available vegetable oil or molybdenum disulfide. For stainless steel, No. 30 engine oil or vulcanized oil can be used.

7) When switching to the latter tap in the tapping process, first screw it into the tapped thread by hand, and then turn it with the wringer when it can no longer be screwed in. When the end cone is withdrawn after tapping, it is also necessary to avoid turning the hand quickly, and it is best to turn it out by hand to ensure that the quality of the tapped thread is not affected.

8) machine attack, tap and screw hole to maintain coaxial.

9) When tapping, the calibration part of the tap cannot be fully out of the head, otherwise the teeth will be disordered when the tap is withdrawn from the reverse car.

10) If the blind hole is tapped, stick the tap on the surface of the workpiece to be tapped before tapping, set the depth to be tapped, and then tap again. After reaching the predetermined depth, quickly reverse the drilling machine to make the tap withdraw. When setting the depth, a few millimeters of margin should be left to prevent the tap from tapping to the end and to avoid the tap breaking. When tapping, the left hand is placed on the spindle handle, and the right hand holds the forward and reverse rotation handle of the drilling machine. This can better operate the rocker drill to work.

11) The cutting speed of machine tapping is generally 6-15 m/min for steel materials; 5-10 m/min for tempered steel or harder steel materials; 2-7 m/min for stainless steel; 8-10 m/min for cast iron. In the same material, the tap diameter is small to take the higher value, the tap diameter is large to take the lower value.