Circular connecting nut - how to correctly use screw fasteners and maintenance requirements?
Flange hex bolts - screw fasteners are highly used hardware products in daily life, and screws are present on almost every device. Below, we will explain how to use screw fasteners correctly.
The specifications for flange hexagonal bolts and screws include: product name (specification), raw materials, strength grade, standards, and surface treatment.
1. Particle board screws - In terms of product types, outer hexagonal screws accept relatively greater torque, inner hexagonal screws accept smaller torque, and cross groove screws accept smaller torque. Particle board screws - In the application of product matching, we usually advocate using screws with a grade one level higher than nuts, which has economic benefits.
2. Hexagonal socket bolt - commodity raw material grade. Here we mainly talk about the carbon steel we commonly use. According to the unevenness of carbon content, we divide it into C1008 (corresponding to grade 4.8), C1035 (corresponding to grade 8.8), C1045 (corresponding to grade 10.9), SCM435 (corresponding to grade 12.9 and 45H), among which the higher the carbon content, the harder the raw material. Screws of grade 8.8 and above are considered high-strength screws.
3. Hexagonal socket bolt - Regarding standards, for example, M4 × 8, the outer diameter of the 4 fingers is 4mm, and the useful length of the 8 fingers embedded in the loaded object is 8mm. Generally, countersunk screws are loaded with the total length, and semi countersunk screws need to add half the length of the head. And the pan head screw cross does not include the head
4. Hexagonal connecting nut - When the same material is heat-treated, the higher the hardness, the poorer the resistance. Electroplating of grade 8.8 or above requires heat treatment. There are two types of heat treatment we are currently doing: hexagonal connecting nuts - high-strength screws require quenching and tempering heat treatment, which means that the hardness of the screw is uniform from the inside out; Self tapping screws require carburizing heat treatment, which means that the outer surface of the screw is coated with a layer of carbon, which is very hard, but the inside is very soft. If carburizing is applied to the inside, the screw will be burnt.
5. Hexagonal coupling nut - typically, with a hardness greater than 32HRC, there is a risk of hydrogen embrittlement during electroplating. Hydrogen embrittlement refers to the phenomenon where H+ions enter the metal and form bubbles during acid washing (oil stains) of the product. The screw remains in use for 24 hours before cracking. Hexagonal connecting nut - therefore, this product with hydrogen embrittlement risk needs to undergo dehydrogenation treatment after electroplating.
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