High-strength screw grade and its application areas solutions

High-strength screw grade and its application areas solutions

High-strength bolts are more widely used in the automotive industry; the analysis of the impact of the anti-loosening performance of high-strength bolts can guide the actual use of the situation, for example, as far as possible by increasing the preload or friction coefficient to improve the anti-loosening performance of the bolt to meet the current anti-loosening needs and reduce the cost of using anti-loosening nuts. Use of some fasteners need to pay attention to their use conditions: the use of spring washers need to control the size of their preload, and if the vibration is more powerful, the spring washer does not have the desired anti-loosening effect; ordinary hexagon head bolts preload lower, the clamping force attenuation is severe.

High-strength screw grade and its characteristics

High-strength screw grade refers to the ability to withstand the more excellent tensile and shear force of the screw in mechanical connectors that have a wide range of applications. Common high-strength screw grade 8.8, 10.9, 12.9, etc., where the number indicates the tensile strength of the screw and the shear strength ratio of the percentage， For example, a grade 8.8 screw suggests that it has a tensile strength of 8 times and a shear strength of 0.8 times. The following are the main characteristics of each grade:

1. Grade 8.8 screws: with a tensile strength of 800 N/mm², they are suitable for general mechanical connections, general construction, and equipment.

2. 10.9-grade screws: tensile strength of 1000N/mm², suitable for mechanical equipment requiring high strength and durability, such as automobiles, locomotives, airplanes, and so on.

3. 12.9-grade screws: tensile strength of 1200N/mm², suitable for mechanical connections requiring higher load capacity, such as significant construction machinery, motorcycle engines, etc.

High-Strength Grade 8 Steel Flanged Hex Head Screws: Made from Grade 8 steel, these screws can be used in high-stress applications, such as valves, pumps, motors, and automotive suspension systems. They are at least 25% stronger than medium-strength steel screws. The flange distributes pressure where the screw meets the surface, eliminating the need for a separate washer. The material meets SAE J429 specifications for quality. Dimensions meet IFI 111 specifications. Grade 8 steel hex head screws are marked with six radial lines. Head height includes the flange. Length is measured from under the flange.

Black-phosphate steel screws are mildly corrosion-resistant in dry environments. Zinc yellow-chromate plated steel screws resist corrosion in wet environments.

Match the thread spacing of mating components. Coarse threads are the industry standard; choose these screws if you don’t know the threads per inch. Fine threads are closely spaced to prevent loosening from vibration.

High-Strength Metric Class 10.9 Steel Hex Head Screws: Choose these Class 10.9 steel screws for high-stress applications, such as valves, pumps, motors, and automotive suspension systems. They are at least 25% stronger than medium-strength steel screws. Dimensions meet ISO (formerly DIN) or DIN specifications. Length is measured from under the head.

Steel screws should be used in dry, noncorrosive environments. Zinc yellow-chromate plated and zinc-plated steel screws resist corrosion in wet environments. Blue-dyed screws are easy to distinguish. Black corrosion-resistant coated steel screws resist chemicals and withstand 1,000 hours of salt spray. To maintain corrosion resistance, use these screws with black ultra-corrosion-resistant-coated nuts and washers.

Match the thread spacing of mating components. Coarse threads are the industry standard; choose these screws if you don’t know the pitch. Fine and extra-fine threads are closely spaced to prevent loosening from vibration; the finer the thread, the better the resistance.

Medium-Strength Metric Class 8.8 Steel Hex Head Screws: These Class 8.8 steel screws are suitable for fastening most machinery and equipment. Dimensions meet ISO (formerly DIN) or DIN specifications. Length is measured from under the head.

Zinc-plated steel screws resist corrosion in wet environments. Black corrosion-resistant-coated steel screws resist chemicals and withstand 1,000 hours of salt spray. To maintain corrosion resistance, use these screws with black ultra-corrosion-resistant-coated nuts and washers.

Match the thread spacing of mating components. Coarse threads are the industry standard; choose these screws if you don’t know the pitch. Fine and extra-fine threads are closely spaced to prevent loosening from vibration; the finer the thread, the better the resistance.

Screws that meet SAE J1199 comply with specifications for material standards.

Application areas of high-strength screws

1. Machinery and equipment field: in machinery manufacturing, high-strength screws are widely used, such as for fixing the various parts of the lathe, grinder, and other machine tools, to ensure the stability and durability of the machine tools.

2. Automotive field: high-strength screws can withstand high-speed driving in the generation of severe shock and vibration, used to fix the car parts, such as the engine, transmission, brake system, etc.

3. Aviation field: aircraft components need to use high-temperature, high-strength screws, such as aircraft engine fasteners, oil and gas piping fasteners, etc.

4. Electronic field: electronic equipment with a large number of screws for assembly; high-strength screws can ensure the stability and reliability of the equipment.

Maintenance of High Strength Screws

High-strength screws require regular maintenance and inspection during use to ensure the performance and reliability of the screws. The following are some standard maintenance methods:

1. Regular inspection: check whether the screws are loose or damaged, and replace the damaged screws in time.

2.Anti-rust treatment: the surface of the screw is susceptible to oxidation and corrosion and needs regular anti-rust treatment.

3. lubrication treatment: screws bear a huge force vector, and lubricant can make them work more smoothly and reduce wear and corrosion.

In short, the selection and application of high-strength screw grade should be combined with their own needs, but also consider its load-bearing capacity and reliability as well as environmental factors and other factors. In the process of use, we also need to carry out regular maintenance and inspection to ensure its performance and reliability.

Made to Japanese Industrial Standards, these Class 10.9 steel screws can be used in high-stress applications, such as valves, pumps, motors, and automotive suspension systems. They are at least 25% stronger than medium-strength steel screws. The flange distributes pressure where the screw meets the surface, eliminating the need for a separate washer. The zinc plating provides corrosion resistance in wet environments. Head height includes the flange. Length is measured from under the flange.

Match the thread spacing of mating components. Coarse threads are the industry standard; choose these screws if you don’t know the pitch. Fine and extra-fine threads are closely spaced to prevent loosening from vibration; the finer the thread, the better the resistance.For high-quality JIS High-Strength Steel Flanged Hex Head Screws for Sheet Metal and professional technical support, please get in touch with us at adelajonly@gmail.com or visit our website at https://www.juxinfasteners.com.