Fasteners on the market, also known as standard parts, is two or more parts (or components) saw a kind of mechanical fastening parts overall general term used when the connection becomes. It is characterized by many different specifications, performance of different purposes, and standardization, serialization, high degree of generalization. Fasteners are the most widely used machine parts, in great demand. Steps / methods 11, the correct choice of products: before use to confirm whether the mechanical properties of the product can meet the requirements, such as screws and nuts tensile proof load. To select the appropriate length of the screw to expose the nut tightened after 1-2 Pitch prevail. 2. Check whether the threads before using rough, whether iron or dirt between threads, these things often lead to deadlock. 33, before you can use to do lubricated fasteners: It is recommended to use butter, molybdenum disulfide, mica, graphite or talcum do lubrication, now generally treated with a wax dip lubrication antilock do. 44, note the use of the method: a, screwed the speed and strength to be appropriate and not too big too fast, as the choice of torque wrench or socket wrench, avoid the use of a spanner wrench or electric wrench. Excessive speed causes rapid temperature rise caused by lock. Imported valve gate b, force direction, the nut must be perpendicular to the axis of the screw screwed. 55, using the locking washer can effectively prevent the problem of tight.