The following are production processes bolts, screws the nut: Material is often used to produce the bolts, screw nuts are steel, stainless steel (201 stainless steel, 304 stainless steel, 416 stainless steel)
1. Surface treatment bolts, screws the nut:
It is for the steel rolls into the oven for 30 hours to soft and malleable steel, dipped in a solution of sulfuric acid to prevent corrosion of steel coils will be discharged through the water and covered with a layer of phosphate, steel processing the temperature in normal conditions and in the face with a large compressive forces.
2. Create bolts, screws the nut:
Steel wire straightening and cutting the rope into the straight lines a little longer bolts, rounded body shaping edges and bolt head bolt head bolt breaking into the first round to give the hexagonal bolts, then keep forging machine head cap bolts.
3. Personnel threaded bolts, screws and nuts:
A special machine to easily forged bolt catch nut bolts on grooving along to bolt pierced the steel is also cold, the big rollers squeeze the grooves along the body of the stud bolts each one often take a sample to measure the diameter, and used to the different gauges, gauge to measure the length of the bolt, another machine thickness and width measurements of the head bolts. Unlike screw hot forged, we cut to the roundabout into the small sample included heated to 1200 ° C to them soft and malleable metal forging a hydraulic forging a hexagonal screws , another a punching machine for processing different machine screws drilling facilities grooves inside the screw, then covered up the screws a varnish layer.
4. Heat bolts, screws and nuts:
Both bolts and screws are put into the kiln at 800 degrees C for a period of one hour, this stage helps bolts and fasteners with solid strength steel in the oil cooling will cause organ structure of reinforced steel further heated screw another hour quality control department will measure the force needed to break the bolts, screw bolts and screws if they would cross stitch standardized test, if the bolt fasteners broken when testing will be disqualified.
5. Plating bolts, screws and nuts:
6. Packing bolts, screws the nut:
It is packaged screw with the packaging box always specify the size and quality of the screw nut.