Code name and standard number of inch thread commonly used abroad Mark code name country and standard number Remarks BSW standard Wyeth coarse thread series, general purpose cylindrical thread British standard BS 84 inch thread with a profile angle of 55° BSF standard Wyeth fine thread series, General Purpose Cylindrical Thread Whit.S Additional Whit.S Optional Series, General Purpose Cylindrical Thread Whit Non-standard thread with Whitworth profile UN Uniform thread of constant pitch series American standard ANSI B1.1 inch thread with 60° profile angle, with Internal and external threads with standard profile (flat or rounded at random) UNC Coarse thread unified thread UNF fine thread unified thread UNEF superfine thread unified thread UNS① Special series unified thread UNR round The uniform thread profile angle of the arc root constant pitch series is 60° inch thread, UNR, UNRC, UNRF, UNREF, UNRS with arc root are only used for external thread without internal thread UNRC arc root coarse thread Series Unified Thread UNRF Circular Root Fine Thread Series Unified Thread UNREF Circular Root Ultra Fine Thread Series Unified Thread UNRS Circular Root Special Series Unified Thread NPT② Generally used for pipe thread American standard ANSI B1.20.1 Profile angle is 60° Inch Pipe Thread NPSC Pipe Fitting Straight Pipe NPTR Pilot Connection Tapered Pipe NPSM Mechanical Connection Straight Pipe NPSL Lock Nut Straight Pipe NPSH Hose Connection Straight Pipe NPTF Dry Seal Standard Tapered Pipe Thread American Standard ANSI B1.20.3 Type I PTF-SAE SHORT Dry Seal Short Taper Pipe Thread Type II NPSF Dry Seal Standard Fuel Oil Straight Pipe Internal Thread III Type NPS1 Dry Seal Standard General Straight Pipe Internal Thread IV Type ACME③ General Purpose Trapezoid Thread American standard ANSI B1.5 Inch drive thread with 29° profile angle ① Dimensions and tolerances All diameter and pitch combinations other than the standard series are calculated using the same formula as the standard series. ② my country's 60° conical pipe thread GB/T12716-1991 is equivalent to it. ③ACME thread includes two kinds of matching trapezoidal threads, general purpose and centering, of which the general purpose thread has the same performance as the trapezoidal thread specified in my country's standard GB/T5796-1986.
Electrical contact element is a kind of low-voltage electrical products and household electrical products widely used in switches, relays, thermostats, circuit breakers, contactors, controllers, timers, etc. There are mainly three types of electrical contact elements. 1. Riveting parts , riveting the rivet on the copper piece; 2. Welding piece, welding the sheet contact on the copper piece; 3. Stamping piece, punching the composite tape into components. Existing rivet contacts on the market at present are usually all made of precious metals, such as a simple metal matrix such as gold or silver. Its electrical contact performance is limited by a single metal material, and its electrical contact performance is poor; and due to certain requirements for metal purity in production, production efficiency is low, and production costs are high, resulting in the production of products that cannot be sold on a large scale in the market. and application.
In the installation of the external electrical components of the high-voltage electrical box, generally, the whole aluminum alloy profile with a T-slot is laid on the shell of the high-voltage electrical box, and then the upper nut is placed in the T-slot, and the bottom of the square nut is provided with a spring , When installing the electrical components, align the mounting holes with the screw holes of the square nut, then screw and tighten the screws to achieve the installation of electrical components. The biggest defect in the above installation process is that the alignment of the mounting hole and the screw hole is not very convenient, and the spring at the bottom of the square nut is easy to be missing. Once the spring is missing or damaged, the square nut cannot be effectively positioned in the T-slot. It makes the alignment of the mounting hole and the screw hole more difficult. Third, the above-mentioned connection and fixing method itself is not particularly ideal.
The necked brake pad rivet includes a head and a shaft, the head and the shaft are integrally connected, and it is characterized in that: the head and the shaft are provided with axial through holes formed by cold heading, so The end of the shaft is provided with a tapered portion formed by cold extrusion and chamfering.
Cabinets are one of the must-have furniture in home improvement homes. They are extremely useful. Various cabinets may be used in kitchens, bathrooms, bedrooms, living rooms, and even balconies. The traditional cabinets are assembled in advance and then placed in the appropriate position, which is very inconvenient to transport. Currently, the commonly used cabinets are spliced together with plates and hardware accessories. During production and transportation, the plates and hardware accessories are independent. For production, processing and transportation, after it is sent to the destination, it is assembled with the plates by screws and other hardware accessories to form the entire cabinet structure. The current cabinet installation structure usually exposes some hardware accessories such as screws on the outside or inside of the cabinet, which not only affects the overall aesthetics, but also scratches the items during use, which affects the use effect. Some designs allow a plastic fastener to be fastened on the outside of hardware accessories (mainly screws). Although it can alleviate the above problems to a certain extent, it still does not fundamentally solve the problem, and the integrity is still not good.
We have many years of experience in the production and sales of screws, nuts, flat washers, etc. The main products are: four-corner welding nuts, circular ring welding terminals, code nuts, fully threaded screws and other products, we can provide you with suitable fastening products piece solution.