For achieving the above purpose, Guangdong Yueluo Hardware Industry Co., Ltd. provides the following technical solutions: a pin, comprising a pin cap and a described pin rod, the pin cap and one end of the pin rod are fixedly connected, and the pin rod There is a convex body, the convex body is fixedly connected with the pin rod, the convex body is located on the pin rod rod body, and the other end of the pin rod is provided with a top connecting body, and the top connecting body is fixedly connected with the pin rod , the top contact body includes several top contact units and discs, each top contact unit is coaxially arranged with the pin rod, the top contact units are sequentially fixedly connected along the axis direction of the pin, the top contact unit is The major diameter of the outer contour of the connecting body is larger than the diameter of the pin rod.
The existing screw generally includes a round table-shaped nail body with one large end and one small end, a threaded section is provided on the radial circumference of the nail body, a small end of the nail body is provided with an inclined tip, and the large end of the nail body is provided with a nail cover. , generally used on materials that are softer than the screw, and drill into the object to be nailed through its own rotation. When drilling, the thread plays the role of rotary cutting, so that the screw is drilled forward, but when the thread cuts the object to be nailed When it is shaken for a long time, the tightening force of the screw in the axial direction is not enough, it is easy to loosen, and there is a potential safety hazard.
The existing method of tightening large screws is generally 1. After the nut is screwed to the connected piece by hammering + nut angle method, use a casing to connect the lever arm of the wrench, or use a free hammer to hammer the plate handle, Rotate the nut an additional angle to obtain the required preload. This is not only a primitive and labor-intensive fastening method, but also has great limitations, such as limited space, or the screw itself is a rotating shaft and so on, it is difficult to use this method.
The blind rivet is realized by pulling the core head. With the help of a force from the inside to the outside, under the action of the unidirectional pulling force, the pulling screw is pulled upwards, which causes the outer collar material to expand and deform, resulting in a sexual tightening force. , After the riveting is completed, the tension screw in the middle part breaks and falls out. Since a large pulling force is required to cause the rivet to expand and deform, the tensile screw is longer and accounts for about 60-80% of the total length of the rivet. At the same time, due to the limitation of the deformation mode, it is difficult for the blind rivet to be made into a hexagonal structure like a rivet nut, so the torsion resistance of its connection is low.
flat washer is also called a flat washer. It is mainly stamped out of an iron plate. The shape is generally a flat washer with a hole in the middle. The size of this hole is generally determined according to customer requirements. There are 9 standards for flat washers in my country. From 2000 to 2002, GB/T97.3-2000, GB/T5286-2001, GB/T95-2002, GB/T96.1-2002, GB/T96.2 were approved and released respectively. -2002, GB/T97.1-2002, GB/T97.2-2002, GB/T97.4-2002 and GB/T5287-2002 Standard for flat washers. According to the performance grade of the flat washer, the author recommends the use of materials: ST12, ST13, Q235, Q215, Q195, etc. can be selected for the 100HV grade, and the surface hardness can reach about 110HV; 08F, 08Al, 10, 10F, etc. can be selected for the 140HV grade etc., the surface hardness can reach about 140HV; for 200HV and 300HV grades, 45, 50, 60, 70 or 65Mn steel should be selected, which can be quenched and tempered by heat treatment to meet the technical requirements of 200~300HV and 300~400HV. Because according to the standard, flat washers of 100HV and 140HV grades can be manufactured from mild steel. Most enterprises use Baosteel materials when selecting materials, which is convenient for cold stamping. The following is a brief description of Baosteel's standards. Compared with the BZJ407-1999 standard, there are major changes in Continuous Cold Rolled Low-Carbon Steel Plates and Strips and the enterprise standard: (1) The grades have been revised and integrated, and the grades have been changed from 8 commonly used to 5. St12 is changed to DC01; ST13 is changed to DC03; St14, St15 is changed to DC04; BSC2 is changed to DC05; St16, St14-T, BSC3 is changed to DC06. (2) The surface quality level is changed from two to three: the higher-level finishing surface (FB), the surface is allowed to have a small amount of defects that do not affect the formability and coating and plating adhesion, such as slight scratches, indentations, Pock, roll printing and oxidation color, etc. Premium Finished Surface (FC) products have no visible defects on the better of the two sides and must meet at least FB requirements on the other side. The super-advanced finishing (FD) product must not have any defects on the better side of the two sides, that is, it cannot affect the appearance quality after painting or the appearance quality after electroplating, and the other side must at least meet the requirements of FB. (3) The surface structure is modified from four to two, and the control value of surface roughness is increased. The average roughness Ra when the surface structure is pitted (D) is 0.6 μm. (4) The provisions on Si and residual elements in the chemical composition of the five grades have been cancelled, and the contents of elements such as C, S, and Alt have been revised.
We have many years of experience in the production and sales of screws, nuts, flat washers, etc. The main products are: T-shaped screws, T-block T-block T-slot pressure plate nuts, pan head screws, wholesale galvanized and other products, we can provide you with Provide the right fastener solution for you.