What is machine screw
Machine screw is also called mechanical screw or bolt. According to different types of head and drive, people usually classify machine screw into many different types.Different types of screw have different function, but the common function is to fasten and set one obejct to another.
According to the head types, people classfied them in to following:
Round headPan headCountersunk head (flat head)Half oval headEtc.
Accroding to the drive types, people classfied them in to following:
SlotedPhillips ( Cross )Hexagon socketPhillips/Slot CombinationTroxEtc.The Phillips ( cross ) drive type screw contact area is wide than sloted drive, it is more easy to screw in object and less broken the drive. so it is mroe widely usded than the others drive types. Hexagon socket screw and trox drive type screw can be applied with large tightening torque, strong connection strength, and the head can be buried in the object; they are commonly used for the joints requiring compact structure and smooth shape.
Accroding to the standards, people classfied them in to following:
| DIN 912 | DIN 7991 |
| Hexagon socket cap screw | Hexagon socket countersunk head screw |
| DIN 7985 | DIN 965 |
| Phillips (cross) pan head screw | Phillips (cross) countersunk head screw |
| DIN 85 | DIN 963 |
| Slotted pan head screw | Slotted countersunk head screw |
etc.
bolt Material:
| Material List | |||
| Stainless Steel | |||
| China | European | American | Propety Class |
| 667 (Low Nickle Stainless steel) | — | ||
| 304 | A2 (1.4303) | AISI 304 | A2-70 |
| 306 | A4 (1.4401) | AISI 201 | A4-70 |
| Carbon Steel and Alloy steel | |||
| China | European | American | Propety Class |
| Q235A(A3) | C35E(CK35) | AISI 1015 | 4.8 |
| 35# | 37Cr4 | AISI 1035 | 8.8 |
| 40Cr | 41Cr4 | AISI 5140 | 10.9 |
| 35CrMo | 34CrMo4 | AISI 4135 | 12.9 |
| Copper | |||
| China | European | American | Propety Class |
| H62 | CuZn40 | ASTM C28000 | — |
| Important Notice: | |||
| 1, All of the above material code is only for reference, the final product material shoud be confrimed by communicate with ASUDA sales 2, If Chinese material standard is different from buyer’s standard please refer to Chinese standard or supplier’s standard |
Property class ( grade ) :
4.8 grade, this grade is most applied, and the material usuall is carbon steel.
8.8 10.9 12.9 grade, these grade are applied for some object need hight strengh request oppelication
A2-70 grade is for Stainless steel 304 material
A4-80 grade is for Stainless steel 316 materail
etc.
Surface finish
Our screws are widely used on lock, plastic toys , electrict equitment and others place