The heating bolt pre-stretching method makes the bolt pre-stretch to the required deformation amount by heating, and then tighten the nut. After cooling, the bolt is shortened and the connection is pre-tightened. This is a commonly used fastening method in infrastructure installations. However, it is not suitable for devices that often need to be disassembled and adjusted, because during the disassembly process, the connected parts will be heated and elongated together with the bolts, and the use of open flame heating will be limited in some occasions; the use of electric heating will make the structure of the screw It becomes complicated and increases the investment, and even if it is difficult to disassemble, such as the propeller shaft of the ship, etc., the heating method is not suitable.
The spring washer usually includes a washer body and a raised claw head punched and formed on the washer body. The spring washer is often placed between the bolt head of the bolt and the connected parts, wherein the raised claw head is connected to the part to be connected. The surfaces of the connecting parts are in contact, and the plane on the gasket body, opposite to the lifting direction of the raised claw head, is in contact with the bolt head. After the bolt head is tightened, the elastic reaction force generated by the raised claw head after flattening makes the The screwed threads are pressed tightly, and at the same time, the raised claw head is pressed against the bolt head and the supporting surface of the connected parts, which has the effect of preventing loosening. However, the traditional spring washer is a single-claw type. When tightening, the raised claw head will cause great damage to the surface of the connected parts, so it is not suitable for the anti-loosening treatment of parts with small surface hardness.
The lifting ring screws are generally not surface treated, but according to the requirements, surface treatment such as galvanized passivation and chrome plating can be carried out, and it is specified in GB5267-85. The chemical composition and mechanical properties of the material should be treated immediately after electro-galvanizing. The test methods are specified in GB699. During routine inspection, the grain size test may not be advanced, and the grain size test method shall be in accordance with the provisions of YB27. Thread inspection is performed with thread gauges and smooth limit gauges or universal energy tools.
The beneficial effects of Guangdong Yueluo Hardware Industry Co., Ltd. are: in Guangdong Yueluo Hardware Industry Co., Ltd., the rivet fixing mechanism is used to temporarily fix and position the rivet, and the pressure cylinder is used to drive the movement of the final shaft, so that the insertion nozzle can be Insert the rivet located in the rivet fixing mechanism into the product. Guangdong Yueluo Hardware Industry Co., Ltd. adopts mechanical drive and transmission, which has a high degree of automation and high work efficiency.
Gaskets are primarily used to protect the bearing surfaces of the coupled pieces. Bolts, nuts, etc. are mostly made of medium carbon steel, and alloy steel is also used. When there are requirements for anti-corrosion or electrical conductivity, copper, copper alloy and other non-ferrous metals can also be used. The standards of China and many countries stipulate that threaded joints are graded according to their mechanical properties, and the grade code is marked on the fastener. The rivet is made of steel, aluminum alloy or copper alloy, etc., and the head has various shapes to meet the needs of different rivet seams.
We have many years of experience in the production and sales of screws, nuts, flat washers, etc. The main products are: hexagon socket head nuts, aluminum alloy toothless hand-adjusting nuts, GB869 countersunk rivets, blank nuts and other products, we can provide you with suitable products. Your fastener solution.