Pre-embedded channels are often used in rail transit. There are usually U-shaped channels and C-shaped channels. There are also various widths of openings on one side. The BristolT-bolts used in their connection are generally non-standard parts, which need to be The actual project needs to be customized, mostly for the overall stamping production, the mold cycle is long, the number of mold openings is large, and the production cost is high. Moreover, when assembling and connecting, it is sometimes found that the size of the originally designed t-bolts does not match, and it is necessary to replace t-bolts of different sizes, then it is necessary to redesign and produce non-standard t-bolts, which slows down the entire equipment. processing cycle. Customized BristolT-bolts are often not wide enough in size range, and only a few can be selected for specific assembly and connection, which is difficult to meet the diverse requirements of the production site for bolts.
The meaning of bolt performance grade is an international standard. Bolts of the same performance grade, regardless of the difference in material and origin, have the same performance, and only the performance grade can be selected in the design. Strength grade The so-called 8.8 and 10.9 grades refer to the shear stress grades of bolts of 0.88GPa and 1.09GPa 8.8 Nominal tensile strength 800N/MM2 Nominal yield strength 640N/MM2 General bolts use XY to indicate the strength, X *100=tensile strength of this bolt, X*100*(Y/10)=yield strength of this bolt (because according to the regulations: yield strength/tensile strength=Y/10, that is, 0.Y is the yield strength ratio ) If the grade is 4.8, the tensile strength of this bolt is: 400MPa; the yield strength is: 400*8/10=320MPa. Another: stainless steel bolts are usually marked as A4-70, A2-70, and the meaning is otherwise explained Measurement: There are two main units of length measurement in the world today, one is the metric system, and the measurement unit is meters (m) and centimeters (cm). ), millimeter (mm), etc., are used more in Europe, my country and Japan and other Southeast Asian regions, the other is the British system, and the unit of measurement is mainly inches (inch), which is used more in the United States, Britain and other European and American countries. 1. Metric measurement: (decimal system) 1m2 =100 cm2=10000 mm2, imperial measurement: (8 decimal system) 1 inch = 8 inches 1 inch = 25.4 mm 3/8¢¢×25.4 =9.523, 1/4 ¢¢ The following products are indicated by their number, such as: 4#, 5#, 6#, 7#, 8#, 10#, 12#
BristolBristolBristolBristolCountersunk head screws are mostly used after installation, and the surface of the parts cannot be raised, and the parts to be fastened have two thicknesses. Thickness, after the screw is tightened, there is still a part of the screw thread that does not enter the threaded hole. In this case, the countersunk head screw can definitely be tightened. There is usually a situation where the thickness of the fastened part is less than the height of the head of the countersunk head screw, which is commonly seen in sheet metal parts in mechanical equipment, such as the connection between the hinge of the chassis and the door and the box; the sheet metal of the equipment The connection of the cover to the equipment, etc. Due to the small thickness of the part, the tightened sheet metal part, the screw through hole completely becomes a conical hole, in this case, when the countersunk head screw is tightened, the screw head is not a tapered surface to press the sheet metal part , but the bottom of the screw head and the top of the threaded hole are squeezed. Although it feels that the screw is tightened, the sheet metal part is stuck instead of being pressed. In this case, although it feels that the screw is tightened, the sheet metal The gold pieces were indeed not tightened. This is a very common situation. Let’s talk about the reasons for the processing: the head cone of the countersunk screw has a 90° conical angle, and the apex angle of the newly bought drill is usually 118°-120°. Some workers who lack training do not know this angle is poor. It is often used to ream the hole with a 120° drill bit, which results in that when the countersunk head screw is tightened, it is not the conical surface of the head, but a line at the bottom of the screw head, which is one of the reasons why the so-called countersunk head screw cannot be tightened. , it's not the screw's fault.
Copper nuts, also known as embedded nuts and embedded copper nuts or plastic embedded nuts, are divided into hot melt copper nuts, hot pressed copper nuts, embedded copper nuts and ultrasonic copper nuts according to different methods of use. This product is widely used in mobile phones. Shell / Pen meter shell / injection molding / insert of plastic parts, used as an internal thread. Generally embossed on the outer circle. To prevent sliding.
In another embodiment of Guangdong Yueluo Hardware Industry Co., Ltd., the slotting device 4 includes a motor 41 and a motor 43, the cutting wheel 42 is fixedly arranged at the output end of the motor 41, and the motor 41 drives the cutting wheel 42 to rotate to open the screw. slot, the motor 43 is fixedly arranged on the workbench 1, the motor 41 is arranged on the motor 43, a track 47 is arranged between the motor 41 and the motor 43, the motor 41 can reciprocate through the track 47, and when the screw is slotted, the motor 41 drives the cutting wheel 42 to move in the direction of the screw. When the slotting is finished, the motor 41 drives the cutting wheel 42 to retract. The fixed wheel 48 is arranged at the output end of the motor 43. The fixed wheel 48 is located directly below the cutting wheel 42. The surface of the middle screw is in contact, and the motor 43 drives the fixed wheel 48 to rotate to grind and polish the surface of the slotted screw to make the surface smooth. Preferably, the direction of rotation of the cutting wheel 42 and the fixed wheel 57 is opposite.
We have many years of experience in the production and sales of screws, nuts, flat washers, etc. The main products are: BristolTorx screws, GB12617.3 rivets, cylindrical connections, copper pads and copper gaskets and other products, we can provide you with suitable fastening products piece solution.