Service HotlineWith the advancement of technology in various industries, the current structural design of screws has evolved from just simple locking to focusing on work efficiency during the locking process and not destroying the integrity of the objects to be locked. New cases such as No. 556784 screw improvement and No. 289415 screw that integrates locking, stability, labor-saving, fast and multi-function which were previously designed and approved and published in the Central Taiwan Bulletin are the main representatives of screws. It is clear that It is learned that the two cases not only fully improve the shortcomings of the traditional simple locking screws, but also achieve the purpose of substantial improvement of the screws designed in each case in actual use.
Anchor bolts are also known as stiffened anchor plate anchor bolts, welded anchor bolts, anchor claw anchor bolts, rib plate anchor bolts, anchor bolts, anchor screws, anchor wires, etc. It is specially designed to be buried in the concrete foundation and used as the base for fixing various machines and equipment. Figure 7 anchor bolts are the most commonly used anchor bolts. It is generally made of Q235 steel, with high strength using Q345B or 16Mn material, and also using 40Cr material to process 8.8-strength products, and occasionally using secondary or tertiary rebar. Anchor bolts are divided into wool, thick rod and thin rod. The wool material is the raw material steel, which is directly processed from round steel or wire without modification; thick rods or called A-type, thin rods or B-type, are processed from steel modified into the corresponding required rod diameter. Welded anchor bolts are made of single-headed bolts welded with stiffened iron plates. Its anti-pulling ability is strong. According to the different conditions of use, it can reach 3.6, 4.8, 6.8, 8.8 and other grades respectively. The tensile capacity of 3.6 grade 7-shaped anchor bolts is the tensile capacity of the steel itself. The tensile strength of anchor bolts directly processed from Q345B or 16Mn raw materials can reach a tensile strength of 5.8. The tensile strength of grades 4.8, 5.8, 6.8 and 8.8 refer to the provisions on mechanical properties in GB/T3098.1.
The flat key is a key that relies on the two sides as the working surface and transmits the torque by the extrusion of the key and the side of the keyway, and is mostly installed on the shaft. If the flat key is used for a long time or is in a bad working environment for a long time, dust, oil, etc. will inevitably be stuck between the flat key and the keyway. Since the flat key has no ejector threaded hole for disassembly, it is difficult to dismantle, and during the disassembly process A little carelessness will cause damage to the flat key.
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.
Therefore, in order to obtain fasteners that meet the requirements, it is usually necessary to anneal the middle sections of bolts, rivets, etc. to reduce the hardness of the middle sections, while ensuring the hardness of the heads of bolts, rivets, etc. At present, the existing process adopts ultra-high frequency induction heating equipment to instantly heat the middle section and reduce the hardness. However, this process requires a lot of control, and the heating time is slightly longer, which affects the hardness of the head, and the mass production is very unstable, which is easy to cause the rivet to fail. At the same time, the cost of ultra-high frequency equipment is high and the power consumption is large, which is not conducive to mass production and energy saving. Environmental friendly.
We have many years of experience in the production and sales of screws, nuts, flat washers, etc. The main products are: carbon steel grade 8.8 hexagon nuts, high-strength screws, hexagon expansion bolts, countersunk head rivet nuts and other products, we can provide you with suitable products for you Fastener Solutions.
