Fasteners are also called standard parts in the market. They are a general term for a class of mechanical parts used when two or more parts (or components) are fastened and connected into a whole. It is characterized by a wide variety of specifications, different performance and uses, and a high degree of standardization, serialization, and generalization. Fasteners are the most widely used mechanical basic parts and are in great demand.
1. Select the product correctly: Before use, confirm whether the mechanical properties of the product can meet the requirements of 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 exposed nut after tightening.
2. Before use, check whether the thread is rough, whether there is iron filings or dirt between the threads, these things often cause lockup.
3. Lubricate the fasteners before use: it is recommended to use butter, molybdenum disulfide, mica, graphite or talc for lubrication. At present, wax dipping is commonly used for lubrication and anti-locking.
4. Pay attention to the method of use:
a. The speed and force of screwing in should be appropriate, not too fast or too big. Use torque wrench or socket wrench as much as possible, and avoid using adjustable wrench or electric wrench. Too fast will cause the temperature to rise rapidly and cause lockup. Import pump valve
b. In the direction of force, the nut must be screwed in perpendicular to the axis of the screw.
5. The use of washers can effectively prevent the problem of over-locking.
6. 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 and will produce a thin oxide layer on the metal surface when the surface is damaged. To prevent further corrosion. When stainless steel fasteners are locked, the pressure and heat generated between the teeth will destroy this oxide layer, causing blockage or shearing between the metal threads, and then 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 of the use of such fasteners can prevent this phenomenon.