Service HotlineWhen using screws, if you can understand the mechanical properties of screws first, then you can use screws better. Different types of screws have different mechanical properties, and the different mechanical properties lead to different occasions when screws are used. 1. Self-tapping screws: mechanical performance requirements 1. Heart hardness: standard value HRC28-38. When testing, take the section 1-2 times the diameter of the name from the tail. If the length of the name is too short, it can be embedded first, and then the hardness is measured. 2. Surface hardness: standard MIN HV450. 3. Carburized layer: standard 4#-6#: 0.05-0.18mm, 8#-12#: 0.10-0.23 mm, 14#: 0.13-0.28 mm. The main purpose of carburizing is to enhance the surface hardness and ensure the strength of the teeth. If the decarburization is too deep and the carburization is insufficient, the strength of the teeth will not meet the requirements, that is, the teeth will be damaged during the screw-in test. 4. Torque: standard specification 4#5#6#7#8#10#12#14#A tooth 14212835455696145AB tooth 142128354565102165. 5. Screw-in test: screw the self-tapping screw into a steel plate with a reserved test hole. The self-tapping screw should form a matching thread in the test plate, and the thread of the screw itself will not be deformed or damaged until the end. Tapered threads pass completely through the test plate. The screw-in test is only applicable to AB, B, BP and other types of self-tapping screws. It is stipulated in IFI that the test plate shall be prepared from semi-hard low-carbon cold-rolled steel, and the hardness of the steel plate is 70–85HRB in Rockwell. The standard specification of the steel plate, that is, the thickness, is shown in the table below. The test hole should be punched or drilled, and the tolerance is the specified nominal diameter (see the table below) ± 0.025mm. Specifications 6#7#8#10#12#1/4 Test plate thickness (mm) 1.85-1.953.12-3.234.68-4.84 Aperture (mm) ±0.0252.953.263.454.044.765.50.
The front wall sound insulation pad is used to absorb the heat and noise transmitted by the firewall, and also plays the role of heat insulation and vibration isolation, ensuring a relatively quiet and comfortable environment in the car and improving ride comfort. As shown in FIGS. 1 and 2 , the front wall sound insulation and heat insulation pad 101 is generally fixed to the vehicle body by means of screw buckles 102 . The screws 100 are clamped by the clamping feet 103 in the screw The limiting rib 104 clamps the screw 100. After the screw 100 is clamped into the screw buckle 102, the tail end of the screw 100 is exposed, which is easy to scratch the operator when assembling other components, and the exposed screw 100 is easy to cause corrosion, thereby affecting the connection strength of the screw 100, and also The service life of the screw 107 is reduced.
The tail of the drill tail screw is in the shape of a drill tail or a pointed tail, and no auxiliary processing is required. Drilling, tapping and locking can be directly carried out on the setting material and basic material, which greatly saves construction time. Compared with ordinary screws, its toughness and pull-out force and maintenance force are high, and it will not loosen for a long time after combination, so it is safe to use. Especially in the combination of construction, construction, residential and other places, self-tapping and self-drilling screws are the best economical fasteners in terms of workability, cost and reliability. Now the construction of high-rise buildings and high-speed traffic in mainland China requires more high-quality drill screws;
Generally, we have to divide the fine thread nut and the coarse thread nut first, but in fact, no matter what kind of fine thread, coarse thread, their specifications are the same, their specifications are M3, M4, M5, M6, M8, M10, etc. . But there is another kind of hexagonal nut, which is divided into English and American, which is only a different national standard. Made in China, it is called the national standard hexagon nut
Further, it also includes a motor, the motor is provided with a thruster that makes the cutting wheel move towards the conveying device, the other end of the motor is provided with a bearing, the output end of the motor is provided with a special-shaped wheel, the special-shaped wheel is toothed with the bearing, and the motor drives the special-shaped wheel to rotate. , move the cut-off wheel closer to or away from the conveyor.
We have many years of experience in the production and sales of screws, nuts, flat washers, etc. The main products are: solid aluminum rivets, round head nuts, DIN934 stainless steel screws, knurled copper posts and other products, we can provide you with suitable fastening products piece solution.
