Five ways to prevent locking of stainless steel fasteners

A type of mechanical parts that are used for fastening connections and are widely used. In all kinds of machinery, equipment, vehicles, ships, railways, bridges, buildings, structures, tools, instruments, meters and supplies, etc., you can see a variety of fasteners. It is characterized by a wide variety of specifications, different performance uses, and standardization, serialization, generalization of the species is also very high. Therefore, some people have also referred to a type of standard fasteners as standard fasteners, or referred to as standard parts.

Fasteners include: studs, nuts, washers, and pins. Locking or seizure often occurs on fasteners made of stainless steel, aluminum alloy and titanium alloy. These metal alloys have anti-corrosion properties and will be damaged on the surface., A thin oxide layer is produced on the metal surface to prevent further corrosion. When the stainless steel fasteners are locked, the pressure and heat generated between the teeth will destroy the oxide layer, so that the metal threads between the blocking or shearing, 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 locked. Usually this series of blocking_shear_adhesive_lock a series of actions occur in just a few seconds, so the correct understanding of the use of such fasteners, in order to prevent this phenomenon.

1. Choose the right product

Before use, confirm whether the mechanical properties of the product can meet the use requirements, such as the tensile strength of the screw and the guaranteed load of the nut. The length of the screw should be selected appropriately, with 1-2 pitch 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 lead to lock.

3. Can be used before the fastener lubrication treatment

It is recommended to use butter, molybdenum disulfide, mica, graphite or talcum powder for lubrication. At present, wax immersion is generally used for lubrication and anti-locking.

4. Pay attention to the use method when using

a. The screwing speed and force should be appropriate, not too fast or too large. 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 the lock.

B. the direction of force, the nut must be perpendicular to the axis of the screw to screw in.

5. The use of washers can effectively prevent the problem of over-locking.