Heat treatment technology has a crucial impact on high-strength fasteners, especially its intrinsic quality. Therefore, in order to produce high-quality high-strength fasteners, advanced heat treatment technology and equipment must be available. 1. Status of heat treatment of high-strength fasteners High-strength fasteners have 4 performance levels, namely 8.8, 9.8, 10.9, and 12.9. These four grades of high-strength fasteners must be quenched and tempered. The purpose of heat treatment and tempering is to improve the comprehensive mechanical properties of fasteners to meet the specified tensile strength value and yield ratio of the product. Therefore, the quenching and tempering process has strict requirements on raw materials, furnace temperature control, furnace atmosphere control, quenching medium, heat treatment quality inspection and control, etc.
Spring washers are often called spring washers in the screw industry. Its materials are stainless steel and carbon steel, and carbon steel is also iron. The commonly used spring washers are M3, M4, M5, M6, M8, M10, M12, M14, M16. These specifications are more commonly used. The national standard for spring washers is GB/T 94.1-87, which specifies standard spring washers with a size of 2-48mm. Reference standard GB94.4-85 Elastic Washer Technical Conditions Spring Washer
Moisture-proof measures Iron screws are easy to rust in a humid environment. In order to prevent the screws from rusting, the screws need to be moisture-proof and moisture-proof. The moisture-proof and moisture-proof methods of screws are as follows: (1) Vibration machinery, try to use solvent-free paint. (2) It is best to use impregnating paints that do not contain oxidative components, such as epoxy-urethane (Epoxy-urethane)-based or unmodified epoxy-based (Epoxy-)-based impregnating paints. (3) When using melamine alkyd impregnating paint, the curing temperature and curing time should be adjusted. The curing temperature should be slightly higher than 130 °C (such as 135 °C) and the curing time should be longer than 180min, and the process must be strictly implemented, especially In the hot and humid season, the drying (curing) time of the paint specified in the paint factory's samples is not necessarily sufficient from the perspective of rust prevention, and the motor has a specific inner shape. (4), use paint without volatile acid. (5) Choose paint with good hydrolysis resistance.
The national standard name of the cross recessed small pan head three-combination screw is the cross recessed small pan head screw, the spring washer and the flat washer assembly. The national label is GB/T9074.8-1988. This 1988 refers to the year, that is, this standard is the standard issued by the country in 1988. The specifications of the cross recessed small pan head three-combination screw, our company's minimum is M2.5, the shortest is 5mm, the largest is M10, and the longest is 90mm. Of course, as customers have higher and higher requirements for small pan head combination screws, or require smaller and longer combination screws. If the quantity is large, or with the development of our company. Buy some advanced combination screw machines. Come and go to meet the higher requirements of our customers.
Guangdong Yueluo Hardware Industry Co., Ltd. discloses a telescopic screw. The main point of its technical solution is that it includes an upper screw rod, one end of the upper screw rod is provided with a screw head, and the other side of the upper screw rod opposite to the screw head is provided with a lower screw rod, and the lower screw rod is provided on the other side. A fixing rod is provided, a limiting hole is set on the fixing rod, a sliding rod is set on the upper screw rod, a limiting block matching the limiting hole is set on the sliding rod, and a cover plate is slidably sleeved on the sliding rod. An inner thread is arranged on the plate, a thread matching the inner thread is arranged on the fixing rod, an elastic member is sleeved on the fixing rod, and both ends of the elastic member are respectively in conflict with the upper screw rod and the lower screw rod. Guangdong Yueluo Hardware Industry Co., Ltd. telescopic screw is provided with a telescopic mechanism between the upper screw and the lower screw. Therefore, the screw can be suitable for threaded installation holes with the same diameter and different lengths, avoiding the screw being limited by the length of the threaded hole and unable to be installed.
We have many years of experience in the production and sales of screws, nuts, flat washers, etc. The main products are: expansion screws with rings, hand-locking screws, square female nuts for practical connectors, nut blocks and other products, we can provide you with suitable products. Your fastener solution.