Surface treatment process
PRODUCTS
Flange bolt: A flange bolt is an integral bolt composed of a hexagonal head and a flange plate (the gasket below the hexagon and the hexagon are fixed together) and a screw (a cylindrical body with external threads). It needs to be matched with a nut and used to tighten the parts connecting two through holes. Therefore, bolt connection is a detachable connection.
Classification
PRODUCTS1. Hexagonal head type: one is flat headed, and the other is concave headed.
2. Surface color category: According to different needs, the surface is coated with white, military green, colored yellow, and corrosion-resistant Dacromet.
3. Category of flange: Depending on the location of the flange bolts used, the size requirements for the flange vary. There are also flat bottomed and toothed types, with toothed ones providing anti slip function.
4. According to force distribution: According to the force distribution of the connection, there are ordinary and hinged holes. The flange bolts used for hinged holes should match the size of the holes and be used when subjected to lateral forces.
In addition, to meet the need for locking after installation, there are holes in the rod, which can prevent the bolt from loosening when subjected to vibration.
Some flange bolts need to be made on the bare rod part without threads, called thin rod flange bolts. This type of flange bolt is beneficial for connecting under variable forces.
Note: Commonly used national standard numbers in the market, GB5789 (large head) and GB16674 replace GB5787 (small head).
Purpose
ProductsThe flange bolt is composed of a hexagonal head and a flange plate, and its "support area to stress area ratio" is greater than that of ordinary bolts. Therefore, this type of bolt can withstand higher pre tightening force and has good anti loosening performance. Therefore, it is widely used in automotive engines, heavy machinery and other products.
Frequently Asked Questions (FAQ)
Q1 What is a flange bolt and how does it function?
A flange bolt is an integral fastener consisting of a hexagonal head, an integrated flange plate acting as a washer, and a threaded screw shaft. It is designed to be paired with a nut to firmly clamp components together in a detachable connection.
Q2 What surface treatments and colors are available for flange bolts?
Depending on functional requirements, flange bolts can be coated in white, military green, colored yellow, or finished with corrosion-resistant Dacromet surface treatment.
Q3 What is the advantage of using toothed flange bolts?
Toothed flange bolts feature serrations on the underside of the flange plate, which provide an anti-slip function and increase resistance against loosening under vibration.
Q4 Why are flange bolts preferred in high-stress applications like automotive engines?
Because flange bolts have a larger "support area to stress area ratio" than ordinary bolts, they can withstand higher pre-tightening forces and provide superior anti-loosening performance in demanding equipment.
Q5 What national standards replace older flange bolt specifications?
Common national standards in the market include GB5789 (for large head flange bolts) and GB16674, which supersede the older GB5787 small head specification.