Twisted shoulder non-standard screw, outer hexagonal half tooth screw, inner hole circular neck irregular bolt

"The spring washer device is located below the nut to prevent it from loosening.
It is explained in national standards.
Hexagonal slotted nuts are specifically designed for use with bolts with holes at the end of the screw to insert the cotter pin into the hole of the screw from the nut groove, preventing the nut from automatically loosening. They are mainly used in situations with vibration or alternating loads.
The methods to prevent automatic loosening of nuts (or bolts) in mechanical design and production include:
1. Add spring washers; (Simple and easy to do)
2. Use hexagonal slotted nuts and split pins; (Increased processing steps compared to the same period last year)
3. Add locking washers; (Increased processing steps compared to the same period last year)
4. Insert the hexagonal head of the hexagonal bolt into the steel wire. (Increased processing steps compared to the same period last year)
Spring washers are used to prevent loosening. For example, the bolts connecting the motor to the base usually need to be equipped with spring washers, because if the motor vibrates without a spring washer, the nut will loosen. Generally, spring washers are installed on the fasteners of equipment with vibration, and there is no need to add washers on the flange! The addition or absence of spring gaskets on the flange is related to the medium in the pipeline flow. If pulse generation is easy, it is best to add spring gaskets. There is also high-speed fluid, and the diameter changes frequently. Do not generalize. Some valves require spring gaskets on the packing box and gland flange The automatic selection of spring gaskets is included"

"Various stainless steel materials have different characteristics due to their different material contents, so their corrosion resistance also varies. Below is a brief explanation of several commonly used materials: 304 is a versatile stainless steel widely used in the production of equipment and machinery that require good comprehensive performance (corrosion resistance and formability).
301 stainless steel exhibits obvious work hardening phenomenon during deformation and is used in various occasions that require high strength.
302 stainless steel is essentially a variant of 304 stainless steel with higher carbon content, which can achieve higher strength through cold rolling.
302B is a type of stainless steel with high silicon content, which has high resistance to high-temperature oxidation.
303 and 303Se are free cutting stainless steels containing sulfur and selenium, respectively, used in situations where easy cutting and high surface gloss are the main requirements.
303Se stainless steel is also used to make machine parts requiring hot heading, because under such conditions, this stainless steel has good Hot working.
304L is a variant of 304 stainless steel with low carbon content, used in situations where welding is required. The lower carbon content minimizes the precipitation of carbides in the heat affected zone near the weld, which may lead to intergranular corrosion (welding erosion) of stainless steel in certain environments.
304N is a type of stainless steel containing nitrogen, which is added to improve the strength of the steel.
316 (18Cr-12Ni-2.5Mo) material: Due to the addition of Mo, its corrosion resistance, atmospheric corrosion resistance, and high-temperature strength are particularly good, and can be used under harsh conditions; Excellent work hardening (non magnetic)"

Usually, we need to first distinguish between fine-tooth nuts and coarse-tooth nuts, but in fact, regardless of the fine-tooth or coarse-tooth teeth, their specifications are the same, including M3, M4, M5, M6, M8, M10, and so on. But there is another type, which includes hexagonal nuts made in English or American, which is only based on different national standards. We produce in China, called national standard hexagonal nuts

"Copper nuts, also known as embedded nuts and embedded copper nuts or plastic embedded nuts, can be divided into hot-melt copper nuts, hot-pressed copper nuts, embedded copper nuts, and ultrasonic copper nuts according to the different usage methods
This product is widely used in Mobile phone case/pen meter case/injection molded part/plastic insert, which is used as an internal thread. Generally, the external circle is embossed to prevent sliding"

A screw is a tool that utilizes the physical and mathematical principles of the oblique circular rotation and friction of an object to gradually tighten the mechanical components of the object. Drill tail screws are screws with a self tapping drilling head at the front end of the screw. The screw has been a common invention in people's production and life for thousands of years, and according to its application field, it is the first great invention of humanity. Drill tail screws are a new invention in recent years, also known as self drilling screws. Screws are a common term for fasteners, commonly used in everyday language.