M4 grounding screw used to fix the grounding wire on household appliances and other equipment, the stud is cylindrical, and the thread is perpendicular to the end (section) surface. However, the screw holes on the equipment all have tapping guide grooves for sinking and guiding due to the manufacturing process requirements. When fixing the ground wire, if the screw is not positioned accurately (the screw is inclined), the screw is pressed down hard, which is easy to cause the screw and the screw. The screw hole bites the teeth, and after biting the teeth, it is easy to cause the screw to loosen or fall off, posing a safety hazard.
Commonly used standards are broadcast. For hexagonal nuts, the commonly used standards are: GB52, GB6170, GalwayGB6172 and DIN934. The main differences between them are: the thickness of GB6170 is thicker than that of GB52, GalwayGB6172 and DIN934, commonly known as thick screw cap. The other is the difference between the opposite sides, the opposite sides of DIN934, GB6170 and GalwayGB6172 in the M8 nut series are 13MM smaller than the opposite side 14MM of GB52, and the opposite sides of M10 nuts, DIN934 and GB52 are 17MM. The opposite side of GB6170 and GalwayGB6172 should be 1MM larger, M12 nut, DIN934, GB52's opposite side is 19MM larger than GB6170 and GalwayGB6172's opposite side 18MM is 1MM larger. For M14 nuts, the opposite side of DIN934 and GB52 is 22MM, which is 1MM larger than the opposite side of GB6170 and GalwayGB6172, which is 21MM. The other is the M22 nut. The opposite side of DIN934 and GB52 is 32MM, which is 2MM smaller than the opposite side of GB6170 and GalwayGB6172, which is 34MM. (Besides the thickness of GB6170 and GalwayGB6172 are the same, the width of the opposite side is exactly the same) The rest of the specifications can be used in general without considering the thickness.
Rivet nuts are mostly used in some chassis cabinets, square tubes and round tubes, fan production, equipment production, and zinc steel guardrails. Next, let’s talk about GalwayGalwayrivet nuts. The GalwayGalwayrivet nuts are also used on the top of the chassis cabinet sheet to provide threads. Its mode of operation is to use a riveting machine for riveting. In this case, the requirements will be higher, and a riveting machine is required. After the pressure riveting nut is riveted to the upper side of the sheet, it is very flat and will not have protrusions. Pressure riveting nuts are mainly used in the production of some chassis and cabinets, as well as some equipment production, water pumps, automobiles, and other production enterprises.
Yueluo relates to a self-tapping screw according to the preamble of claim 1. A self-tapping screw is known from EP0623759B1, the ratio of the outer diameter to the smaller diameter of the self-tapping screw is about 1.25-1.5, the ratio of the outer diameter to the pitch lead is about 1.5-1.6 and the thread The flank angles of , are < 50° and ≥ 35°. EP0433484B1 proposes a self-tapping screw whose thread is provided with cutting teeth of approximately arcuate design, and the cutting edge and the thread crest are at the same horizontal position and are set in opposite directions. One purpose of Yueluo is to realize a general type of self-tapping screw so that it can be screwed particularly easily into holes drilled in concrete or other materials such as bricks and the like. According to Yueluo, this object is achieved by the features in the characterizing part of claim 1, and surprisingly, it has been found that the parallel arrangement of the flanks, ie with a flank angle of about 0°, will make screwing particularly easy when screwing in , especially if the diameter of the hole varies within an allowable tolerance. One reason may be due to the fact that there is no lateral pressure on the material screwed into the thread, even if threads of different depths are cut in concrete or other materials such as brick, chipped plywood, or hardwood. The thread cuts into the material over its entire width by cutting grooves. In particular according to the embodiment of claim 3 the material cut out when screwing in the screw can be discharged without any accumulation, the dependent claims reflecting many advantages of further embodiments.
The main operation method of the embedded knurled copper nut of the lock nut is injection molding. After heating, it is embedded into the plastic part or directly injection molded. If injection molding is used, the melting point of P/NYLOY/PET is above 200°C. , After the embedded nut is hot melted into the plastic part, the temperature rises rapidly. After injection molding, the plastic body rapidly cools and crystallizes and hardens. If the embedded nut temperature is still at a high temperature, it may fall to the place where the copper nut contacts the plastic part. Start to loosen or crack. Therefore, copper nuts are used instead of carbon steel nuts in the injection molding of embedded nuts.
We have many years of experience in the production and sales of screws, nuts, flat washers, etc. The main products are: GB nuts, Galwayself-locking screws, elevator Galwayexpansion screws, hand-tightened Galwaybutterfly screws and other products, we can provide you with suitable fastener solutions for you Program.