​WTI Fasteners

잠재적인 문제

Pushing down on the insert during installation i.e. exerting downward pressure.

해결책

Turn the inserting tool at 180 degree intervals so you are winding the insert into the tapped hole rather than pushing it in. Using a threaded mandrel will also help with metric fine pitch inserts.

이유

The insert is installed too deep into the thread run-out of the tapped hole, either too far down or flush with the other side of the tapped hole.

해결책

Using the depth stop on the tool, wind the insert in to a shallower depth.

이유

The tap isn’t cutting full thread to the bottom of the hole (tapered).

해결책

Drill and tap deeper to the correct depth. Use a bottoming tap to produce threads to the bottom of the hole.

이유

1. Using the incorrect size of tang break tool.

2. Insufficient depth of full thread in the tapped hole or the punch isn’t being held squarely.

3.The tang break tool is damaged e.g. it has become rounded.

해결책

1. Use the correct size tool.

2. Drill and tap to the correct depth of the tapped hole. Rest the tool squarely onto the tang in the vertical position, then strike the punch using a sharp blow with a small hammer.

3. Grind the end of the pin punch or replace it with a new item.

이유

1. An incorrect or oversize drill size has been used, resulting in insufficient thread support.

2. The bolt isn’t fully engaging the full length of the insert.

3. Over-tightening of the bolt beyond shear strength of the component material so that the threads rip out.

해결

1.Check the drill size and gauge the tapped hole.

2. Depending upon the required thread assembly strength, either use a longer bolt or a shorter insert. Check the depth of the tapped holes.

3. Calculate the appropriate shear strength.

원인

1. The insert is cross threading on installation.

2. The tang has not broken off or has not been removed correctly.

해결책

1. Review the installation method being used. Ensure the tool is set correctly and keep the tool square to the job during installation. Ensure only a very light axial pressure is employed. Using a threaded mandrel tool will also help with metric fine pitch inserts.

2. Check the tang has been fully and correctly detached.

원인

1. The hole has been drilled and tapped undersize.

2. Poor quality threads.

3. Burr could be causing an obstruction.

4. The insert is not being presented to the hole squarely or is not being supported, meaning the tool is not set correctly.

해결책

1. Gauge the tapped hole and check the drill size required. Replace the worn drill and tap as necessary. Ensure a wire thread insert tap is being used.

2. Replace the worn tap and gauge the tapped hole.

3. Countersink the hole.

4. Check the correct size and type of tool is being used. Set the tool correctly and hold it at a right angle to the work piece i.e. perpendicular to the piece.