What are the precautions for the use of twin-screw extruder screw sleeves

The thread sleeves of twin-screw extruders are commonly used in angle thread workpieces. In addition to mechanical processing, the threads can also be obtained by tapping and sleeve threads in the pliers processing method. Twin-screw extruder thread sleeve tapping (also known as tapping) is to use a tap to process the inner thread on the inner cylindrical surface of the workpiece; sleeve thread (or sleeve thread, sleeve button) is to use die to process external thread on cylindrical rod .

Five precautions for the use of twin-screw extruder screw sleeves:

1.Drilling holes for twin-screw threaded sleeves

Use the standard drill bits listed in the table to drill holes to a depth greater than or equal to the installation depth of the wire threaded inserts; be careful not to drill the holes into a tapered shape and to prevent chips from falling into them. After drilling, the hole should not exceed 0.4 pitch depth, because the hole is too large, which is not conducive to the screwing of the wire screw.

2. Double screw thread sleeve tapping

Use the wire screw tap with the specified thread specification for tapping. The tapping length must exceed the length of the wire screw. For through holes, all tapping is required; the accuracy of tapping determines the tolerance zone of the final standard internal screw hole. To properly select the tapping method and lubrication, the blind hole tapping should use appropriate force to prevent the tap from breaking. After tapping, the threaded holes should be cleaned, generally with a compressed air spray gun, and a long spray gun with a diameter-like hole should be used to clean the blind holes from bottom to top, and the threaded holes can also be cleaned by cleaning. When the precision of the threaded hole is high, the wire screw sleeve bottom hole plug gauge should be used for inspection.

3. Double screw thread sleeve installation

In general, the wire screw sleeve should be installed with a manual installer. Put the wire threaded sleeve into the installation tool, make the installation handle embedded in the guide rod groove, and turn the handle of the installation tool to screw the wire threaded sleeve into the screw hole, and leave 0.25---0.75 holes of thread from the surface. When installing a small amount of wire threaded inserts and when installing wire threaded inserts with thick threads above M14*2, you can use "T" slotted or threaded head simple tools to install, and be careful not to exert a large axial force on the installation handle of the wire threaded inserts To prevent "clutter". After the wire screw sleeve is installed, in order to check the accuracy level of the standard internal thread hole formed, the corresponding level plug gauge can be used to check.

4. Double screw thread sleeve to handle

For wire threaded inserts with broken grooves, the mounting handle should be removed after screwing into the screw hole, and a handle removal tool is required. When the through hole is used, the installation handle of the wire screw sleeve should be broken. Generally, a punch is used to align the installation handle, and a hammer of about 200g can be used to remove it. The above fine wire screw sleeves can be broken by bending the mounting handle up and down with needle nose pliers. Then remove the broken mounting handle from the screw hole.

5. If you use an automatic Parallel twin screw barrel breaker, you only need to use the punch of the automatic breaker to press the wire screw sleeve installed in the bottom hole with an appropriate force to break the installation handle.