Service Hotlineleak-proof combined gasket relates to a gasket and solves the problem of short service life of the existing gasket. The combined gasket comprises: an O-shaped sealing ring, which is an annular sealing ring with an outer diameter of D and an inner diameter of E. The section diameter is A; the steel outer ring is a steel flat annular outer ring, which is sleeved on the outer surface of the O-ring, the inner diameter is F, and F=D, the thickness is B, B=0.785A ;The steel inner ring is a steel flat annular inner ring, embedded in the inner surface of the O-ring, the outer diameter is G, and G=E; the thickness is C, and C=B. When the O-ring in the combined washer is pressed by the bolt for sealing, it is positioned between the steel outer ring and the steel inner ring, and is protected by both of them, so that the tightening torque of the bolt can be reduced at least Double the sealing performance without reducing the sealing performance, extending the service life of the thread and reducing the production cost.
However, due to a radial external tension, the external tension is caused by the tightening axial force generated by the tightening torque, and the phenomenon of open ring expansion occurs, and the spring washer often breaks due to hydrogen embrittlement. The nut exerts uneven pressure on the flat washer through the spring washer. And the friction coefficient between the spring washer and the nut and the flat washer is very small, and the phenomenon of vibration, rotation and relaxation occurs.
1. For low strength (below 500 N/mm2 or below 60000 psi) bolts use general soft steel, generally use SAE 1008 or JIS SWRM 8 (or SWRCH 8). 2. Lower strength (600 N/mm2 or 74000 psi) ) bolts use general soft steel, but limited carbon content grade, generally use SAE 1010 - 1015 or JIS SWRM 10 - 15 (or SWRCH 10 - 15). .3. Higher strength ( 800 N/mm2 or 125000 psi ) bolts of medium carbon steel, low carbon boron steel plus quenching and tempering, generally use SAE 1035 - 1040 or SWRCH 35K - 40K. 4. High strength (900 N/mm2 or more or 150000 psi or more) bolts use medium carbon Alloy steel or low carbon boron steel, in terms of application, if the metric Class 10.9 uses low carbon boron steel, the imprint should be added under the series imprint to become 10.9, and the imprint of the inch 8.2 grade is also used with the general Grade 8 bolts The imprint is different for easy identification. High-strength bolts made of low carbon boron steel cannot be used in high temperature conditions. The design strength exceeds Class 12.9 or ASTM A574 ultra-high strength bolts are limited to medium carbon alloy steel plus quenching and tempering. The performance grades of bolts for steel structure connection are divided into more than 10 grades such as 3.6, 4.6, 4.8, 5.6, 6.8, 8.8, 9.8, 10.9, 12.9, etc. Among them, the bolts of grade 8.8 and above are made of low-carbon alloy steel or medium-carbon steel and are heat-treated (quenching, tempering), commonly known as high-strength bolts, the rest are commonly known as ordinary bolts. The bolt performance grade label consists of two parts of numbers, which represent the nominal tensile strength value and yield ratio of the bolt material respectively. For example, a bolt with a performance level of 4.6 means: 1. The nominal tensile strength of the bolt material is 400MPa; 2. The yield ratio of the bolt material is 0.6; 3. The nominal yield strength of the bolt material is 400×0.6=240Mpa . Performance level 10.9 high-strength bolts, after heat treatment, can achieve: 1. The nominal tensile strength of the bolt material is 1000MPa; 2. The yield ratio of the bolt material is 0.9; High-strength bolts, processing and manufacturing problems are compared Small, general fastener manufacturing companies can master the manufacturing process; but problems are prone to occur in material selection and heat treatment. Material selection is the primary link. Various alloying elements have a great influence on the properties of the material, and the material must be subjected to spectral composition analysis; secondly, the fracture problem and the choice of heat treatment process have a great influence and are very important. Dealers and traders must control the inspection and performance testing links; automotive fasteners have high requirements and must carefully control the quality.
Screws are commonly found in machinery, electrical appliances and buildings. They are generally made of metal or plastic, cylindrical in shape, and grooves engraved on the surface are called screw threads. The main function of the screw is to join two objects, or to fix the position of an object. Screws can often be removed or re-tightened at will without compromising their efficiency. Generally, the diameter of the top of the screw is larger, and the common ones are round, square or regular hexagon. If the top is regular hexagon, you can turn the screw with a wrench. If the top is round, there will also be grooves on the front of the top, which is convenient for use screwdriver to turn the screw. *The common grooves are one-shaped, cross-shaped and square, and there are other shapes. The grooves of the existing screws are often easy to wear, which makes the screws inconvenient to use and causes the screws to be scrapped. In addition, because the screws have no chip removal The structure makes it difficult for the screw to penetrate other objects, which affects the efficiency of the screw.
self-locking screw comprises a screw main body, a metal screw head is arranged on the upper part of the screw main body, a thread is arranged in the middle part of the screw main body, an interference groove is arranged on both sides of the upper part of the screw main body, and the line of the interference groove is arranged. The included angle is 280-365° with the horizontal line. The bottom of the screw body is provided with an elastic chuck, and the elastic chuck includes an optical axis and a conical head. Guangdong Yueluo Hardware Industry Co., Ltd. Guangdong Yueluo Hardware Industry Co., Ltd. adopts the design of elastic collet, and the screw is provided with threaded segments and interference grooves, so that during the screwing process, the interference groove of the optical axis between the two threaded segments is formed along the screw. The axial elastic force achieves the effect of reliable self-locking, which is easy to use and has high tuning efficiency.
We have many years of experience in the production and sales of screws, nuts, flat washers, etc. The main products are: street lamp screws, semi-hollow rivets, square nuts, blind hole rivet nuts and other products, we can provide you with suitable fastener solutions for you Program.
