Sems Screws
Phillips Pan Head Sems Machine Screws Double Washer Flat And Spring Metric M3 M4 M5 For PCB Mounting
Sems screws are fasteners that come with a washer already installed on the screw. You do not need to pick up a separate washer and put it on the screw. This saves time on the assembly line and reduces loose parts.
How Sems Screws Work
The washer sits under the screw head and stays there. It cannot fall off. You just grab the screw and drive it in. The washer is right where you need it every time. This design also prevents washer loss during maintenance or reassembly.
Washer Options
Spring washer gives you anti vibration locking. Good for machinery and moving parts.
Flat washer spreads out the clamping pressure. Good for soft materials like plastic and aluminum.
External tooth lock washer has teeth that bite into the surface. Good for high vibration applications.
Internal tooth lock washer has teeth that grip the screw head. Provides a clean outward appearance without snagging.
Double washer combines spring and flat washers. Best of both worlds for demanding applications.
Head Styles
Phillips pan head is the most common. Works with standard cross tip screwdrivers. Provides a wide bearing surface for clamping.
Hex head works with wrenches or sockets. Good for higher torque applications where a screwdriver might not provide enough force.
Materials
Stainless steel 304 sems screws offer good corrosion resistance for outdoor and wet areas. Stainless steel 316 provides enhanced resistance for marine environments.
Carbon steel sems screws with zinc plating provide good strength at a cost effective price point. Zinc coating offers mild corrosion protection for indoor and general purpose use.
Size Range
Metric sizes M3 M4 M5 M6. Standard lengths from 6mm to 30mm. Custom sizes available for OEM orders.
Strength Grades
Class 8.8 for medium to high strength applications. Class 10.9 for higher strength requirements. Class 12.9 for maximum strength in demanding applications.
Applications
Sems screws are widely used for electronics assembly, PCB mounting, control panels, industrial equipment, automotive components, marine enclosures, HVAC units, and general factory assembly where speed and reliability matter.
Quality
All sems screws undergo thread gauging and dimensional inspection. ISO 9001 certified quality management system. Various strength grades available. Custom manufacturing for special head styles and washer combinations. Bulk wholesale pricing with factory direct shipping worldwide.
- Pre assembled washer saves assembly time
- Spring washer for anti vibration locking
- External tooth lock washer for high vibration
- Double washer spring plus flat combination
- Phillips pan head and hex head styles
- Stainless steel and carbon steel options
- Metric M3 to M6 Class 8.8 10.9 12.9
| As a certified fastener manufacturer, we support OEM/ODM orders with full ISO certifications. |
| Feel free to contact us for bulk pricing, samples, or technical support. |