1. Choose the right product
Confirm whether the mechanical properties of the product can meet the application requirements before use, such as the tensile strength of the screw and the guaranteed load of the nut. The length of the screw should be selected appropriately, which shall be subject to 1-2 pitches of the revealed nut after tightening.
2. Before using, check whether the thread is rough, whether there is iron filings or dirt between the threads, these things often cause lockup.
3. Be able to smooth the fasteners before use
It is recommended to use butter, molybdenum disulfide, mica, graphite or talc for smoothing. At present, wax dipping is commonly used to prevent lock-up.
4. Pay attention to how to use it
A, the speed and force of screwing in should be appropriate, not too fast or too big. Use a torque wrench or socket wrench as much as possible to prevent the use of adjustable wrenches or electric wrenches. Too fast will cause the temperature to rise rapidly and cause lockup.
B. In the direction of force, the nut must be perpendicular to the axis of the screw to stop screwing.
5. The use of washers can effectively avoid the problem of over-locking.
Locking or seizure often occurs on fasteners made of stainless steel, aluminum alloy and titanium alloy materials. These metal alloys themselves have anti-corrosion properties. When the surface is damaged, a thin oxide layer is formed on the surface of the metal to avoid Further corrosion. When the stainless steel fasteners are locked, the pressure and heat generated between the teeth will destroy the oxide layer, causing blockage or shearing between the metal threads, and then the phenomenon of adhesion. When this phenomenon continues to occur, the stainless steel fasteners will be completely locked and can no longer be removed or continued to be locked. Usually, this series of blocking, shearing, adhering, and locking actions takes only a few seconds, so the correct understanding and use of these types of fasteners can prevent this phenomenon.
How to prevent the locking of stainless steel fasteners
