Service HotlineThere are two types of bolt detection: manual and machine. Manual is the most primitive and the most commonly used consistent detection method. In order to minimize the outflow of defective products, general production enterprise personnel inspect the packaged or shipped products by visual means to exclude defective products (defects include tooth damage, mixed materials, rust, etc.). [2] Another way is automatic machine inspection, mainly magnetic particle inspection. Magnetic particle inspection is to use the interaction between the leakage magnetic field at the defect of the bolt and the magnetic powder, aiming at the difference between the magnetic permeability of the bolts (such as cracks, slag inclusions, mixed materials, etc.) and the magnetic permeability of steel, these materials are discontinuous after magnetization. The magnetic field at the place will be turbulent, and a leakage magnetic field will be generated on the surface of the workpiece where part of the magnetic flux leaks, thereby attracting the magnetic powder to form the magnetic powder accumulation at the defect—magnetic traces. The accumulation of these magnetic powders is observed and explained, and the purpose of rejecting defective products has been achieved.
The lifting ring screw should be made of 20 or 25 steel (GB699). The lifting ring screw must be forged as a whole. The forgings should be normalized and the oxide scale should be removed. The grain size of the finished product should not be lower than grade 5 (YB27-77). There must be over-burning, crack defects.
In the prior art, spring pads are fixed to the seat pan or to the height adjuster tube. However, in the absence of a seat pan, additional components are required to secure the spring pads to prevent movement of the spring pads in the longitudinal direction of the vehicle. FIG. 1 shows such a seat spring pad 2 , which is fixed to the seat pad 1 by means of additional fixing parts 4 . Additional weight is added due to the use of additional fixing parts and a separate step is required in the assembly process to connect the fixing parts to the spring pads. During use, there may be noise between the spring cushion and the seat cushion
At present, in the field of building curtain wall, factory building support structure, shelf structure and other fields of steel structure connection, if closed profiles (such as rectangular steel pipes) are used as the connection structure, welding connection is generally used, and bolt connection cannot be realized. The reason why a bolted connection is not possible is that the profile is a closed structure and it is not possible to place the bolt at the connection location because the size of the bolt head is larger than the thread hole diameter on the profile. Welded connections affect the structural quality of outdoor projects, with poor corrosion resistance, reduced structural strength, and frequent fire accidents. However, the existing non-welded steel structure and the fastening connection of the bracket have complicated T-bolt structure, troublesome processing technology and high production cost.
The installation of the pressure riveting nut is exquisite. If the installation method is not correct, the riveting will not be firm after the pressure riveting. For example, one of our customers reported that the nut would fall off after riveting. Our technicians found that many customers hit it with a hammer or other impact methods, because the installation method of the riveting nut will cause pressure. The uneven force of the rivet nut seriously affects the riveting effect. It looks like it is pressed in on the surface, but in fact, the flower teeth of the rivet nut are not riveted with the plate at all, so it is definitely not riveted. To install the rivet nut, you must use special installation equipment, or simply install it with a press and stamping equipment (generally factories will have these simple equipment).
We have many years of experience in the production and sales of screws, nuts, flat washers, etc. The main products are: cheap DIN547 stainless steel, nickel-plated female screw rivets, precision locking nuts, ANSI lifting ring screws and other products, we can provide you with suitable products for you Fastener Solutions.
