Sems Screws
Hex Head SEMS Screws with Dual Washers
Product Overview
Our hex head SEMS screws adopt factory pre-assembly design, permanently match one flat washer and one spring washer with hex head bolt. Compared with purchasing screws and washers separately, this integrated structure greatly boosts on-site assembly efficiency, stabilizes anti-loosening performance. The external hex head fits socket, pneumatic torque wrench to bear larger tightening torque, widely used for heavy-duty fastening scenarios across multiple industries. We provide complete material, surface treatment and size customization for bulk industrial procurement.
Core Product Features
1. High Torque Hex Head Structure
Outer hexagonal head can be fully clamped by standard socket tools, avoid head slipping during high torque tightening. Suitable for thick metal frame, load-bearing bracket installation that cross recess screws cannot meet torque requirement.
2. Built‑in Dual Washers for Stable Performance
Spring washer supplies continuous elastic preload to resist vibration loosening caused by motor operation, vehicle driving and outdoor equipment swing; flat washer disperses surface pressure to prevent indentation, coating damage on thin metal, galvanized workpieces. Two washers are fixed on screw in advance to avoid missing parts during assembly.
3. Diversified Material Selection
Carbon steel: cost-effective choice for general industrial, indoor equipment fastening, good comprehensive mechanical strength
SUS304 stainless steel: moderate corrosion resistance, fit humid workshop, conventional outdoor equipment
SUS316 stainless steel: superior salt spray & corrosion resistance, applied for coastal, humid, chemical exposure working environment
4. Multiple Surface Treatment Options
Zinc plating, nickel plating, black oxide are optional; we can adjust salt spray testing duration according to customer application requirement to achieve target anti-rust performance.
5. Custom Manufacturing Available
Support custom thread size, screw length, washer thickness, head dimension. OEM order for special non-standard hex head SEMS screws is acceptable with low MOQ negotiation.
Typical Application Industries
Industrial Machinery
Used for motor housing, equipment support frame, control cabinet, transmission bracket fastening on automated production lines.
Automotive Manufacturing
Fit chassis auxiliary brackets, battery pack fixtures, vehicle electronic module mounting needing reliable vibration resistance.
New Energy & Power
Apply to photovoltaic brackets, energy storage cabinet frames, charging pile shells, high‑voltage electrical enclosure installation.
Electrical Infrastructure
Installed on large distribution cabinets, outdoor electrical boxes, industrial terminal equipment for high-torque assembly.
Product Specification & Order Information
Standard Stock Specifications
Common metric thread M3–M12, conventional lengths from 6mm to 50mm are in stock for immediate delivery.
Custom Process
You only need to provide drawings or key parameters including thread, length, material, surface finish; our engineering team will confirm feasibility and offer formal quotation quickly.
Bulk Order Advantage
Pre-assembled hex head SEMS screws reduce your inventory SKU quantity, cut manual washer assembly labor cost, shorten your on-site construction cycle.
FAQ
Q: Can you provide custom size hex head SEMS screws?
A: Yes, we support OEM customized dimensions according to your drawings.
Q: What surface treatment is best for outdoor usage?
A: Zinc plating with high salt spray resistance or SUS316 stainless steel is recommended for outdoor scenarios.
Q: Are the washers permanently fixed on screws?
A: They are pre-assembled and will not fall off under normal transportation and assembly operations.
About Our Company
YH Fastener is a professional fastener manufacturer with decades of production experience, focusing on developing and manufacturing various SEMS screws, standard bolts, customized fastener solutions. Equipped with precision stamping, thread rolling, heat treatment and surface treatment workshops, we can control machining tolerance down to 0.04μm to guarantee stable product quality.
Our hex head SEMS screws and other combination fasteners have been widely supplied to automotive, new energy, industrial machinery, electrical infrastructure industries, and we have built long‑term cooperative relationships with many well‑known hardware buyers worldwide. We support full OEM services including custom dimensions, material selection, surface finish adjustment and packaging. Strict incoming material inspection, production sampling test and finished product salt spray testing are carried out for every batch, to make sure goods can adapt to complicated working conditions of overseas clients. If you have fastener procurement or customized development demands, feel free to send us drawings for quotation.
