What is the tolerance range of precision screws?
What is the tolerance range of precision screws?
Basic requirements for the installation of T-bolt sleeve components: only when the T-head and the middle slot of the anchoring plate are in good agreement and the anchoring surfaces are in close contact, can the force be evenly applied. If the T-head and the anchoring plate are in line contact, even only point contact , the bolt is partially stressed, which will seriously affect the life. Therefore, the verticality of the sleeve installation must be less than or equal to 1/1000, that is, the horizontality of the anchoring plate surface must be less than or equal to 1/1000, and the center deviation of the sleeve must be controlled within 5mm (the center deviation of the T-bolt is 2mm). Therefore, improving the embedded accuracy of the T-bolt sleeve is the key to the installation of the T-bolt integral sleeve.
Cylindrical pins are widely used, and they are usually provided with matching pin holes. For the tails of cylindrical pins exposed outside the pin holes, they usually do not have a guiding function, which cannot meet the needs of quick installation of workpieces.
The material of the round head three combination screw is divided into iron and stainless steel. The iron ones are made of different iron screw wires. Generally, the wire of the combination screw is 1010, 1018, 10B21 and so on. 10B21 is used to make 8.8 grade combination screws. Like 8.8-grade socket head cap screws, 10B21 wires are often used to make them. When done, go to heat treatment. After heat treatment, remove hydrogen and electroplating. This is to prevent the spring washer of the socket head cap screw from breaking. Stainless steel combination screws, in the combination screw market, generally refer to stainless steel SUS304 combination screws. 201 combination screws generally do very little. Few manufacturers of round head three combination screws produce 201 combination screws. Because the hardness of the screw wire of stainless steel 201 is not well controlled, it is easy to produce cracks. Introduction to the basic knowledge of electroplating round head combination screw electroplating generally refers to the de-plating of iron combination screws. Electroplating is divided into environmental protection and non-environmental protection. Commonly used combination screw electroplating colors include green color zinc, green blue zinc, green white zinc, green nickel, red color, white zinc, white nickel, etc. Cross recessed combination screws, hexagon combination bolts and self-tapping combination screws are used in the same way as the corresponding cross recessed screws, hexagon head bolts and self-tapping screws. The main feature of these combination screws is that they are equipped with corresponding washers, which are very convenient to use.
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 11 the result is that 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 above content is uploaded by Yueluo or the Internet. If there is any copyright issue, please contact [email protected].
