Address
304 North Cardinal St.
Dorchester Center, MA 02124
Work Hours
Monday to Friday: 7AM - 7PM
Weekend: 10AM - 5PM
Address
304 North Cardinal St.
Dorchester Center, MA 02124
Work Hours
Monday to Friday: 7AM - 7PM
Weekend: 10AM - 5PM

The combination screw is a type of fastening component that integrates the screw and the washer (flat washer, spring washer or combined washer) during the pre-assembly process. It is widely used in automotive manufacturing, electronic equipment, instruments and meters, and precision machinery. The nickel alloy combination screws supplied by us are made from high-quality nickel-based alloy bars and wires. They are processed through multiple precision procedures such as cold heading/heat forging, threading/rolling, washer stamping, pre-assembly, solution heat treatment, and surface treatment, featuring efficient installation, reliable anti-loosening, excellent corrosion resistance, and convenient material management. They are specifically designed for precise connections in demanding conditions such as marine engineering, petrochemical industry, and nuclear energy.
Assembly Types:
Screw + Flat Washer: Increasing bearing area, protecting connection surfaces
Screw + Spring Washer: Providing elastic preload, preventing loosening
Screw + Flat Washer + Spring Washer: Combining surface protection and anti-loosening functions
Screw + Lock Washer: Suitable for vibration conditions, better anti-loosening performance
Common Screw and Washer Assembly Specifications Reference Table (per DIN 6900):
| Nominal Diameter d (mm) | Head Type | Washer Type | Washer OD (mm) | Washer Thickness (mm) |
| M3 | Pan Head/Phillips | Flat+Spring | 7 | 0.5+0.5 |
| M4 | Pan Head/Phillips | Flat+Spring | 9 | 0.8+0.8 |
| M5 | Pan Head/Phillips | Flat+Spring | 10 | 1.0+1.0 |
| M6 | Pan Head/Phillips | Flat+Spring | 12 | 1.6+1.6 |
| M8 | Pan Head/Phillips | Flat+Spring | 16 | 1.6+2.0 |
| M10 | Pan Head/Phillips | Flat+Spring | 20 | 2.0+2.5 |
Common Head Type Dimensions Reference:
| Head Type | Diameter d (mm) | Head Diameter (mm) | Head Height (mm) | Drive Type |
| Pan Head | M6 | 12 | 3.9 | Phillips/Hex Socket |
| Countersunk Head | M6 | 12.6 | 3.3 | Phillips/Hex Socket |
| Cylindrical Head | M6 | 10 | 4 | Hex Socket |
| Hex Head | M6 | 10 (Across Flats) | 4 | External Hex |
Special Specification Notes: