Sems Screws
Hex Head SEMS Screws Pre‑Assembled Flat & Spring Washer Industrial Combination Fasteners
Product Overview
Our hex head sems screws are factory pre‑integrated with one flat washer and one spring washer into a single captive fastener assembly. The matched washers stay locked on the screw shank yet rotate freely during installation, eliminating manual sorting and pairing work on automated production lines. This series is produced strictly following DIN industrial standards, with full size coverage for metric specifications to match diverse industrial fastening demands.
Structural Advantages
The hexagonal outer head design delivers larger torque bearing capacity compared with pan head variants, suitable for high‑torque tightening scenarios in heavy‑duty equipment. The spring washer embedded in sems screws provides sustained anti‑loosening elasticity under long‑term mechanical vibration, effectively preventing loose connections caused by equipment operation jitter. The enlarged flat washer evenly dist fastening pressure on contact surfaces, avoiding indentation and deformation of thin metal plates and painted workpieces during locking.
Material Selection & Surface Treatment
Multiple raw material grades are optional for hex head sems screws. Carbon steel offers excellent cost performance for conventional indoor machinery assembly; SUS304 and SUS316 stainless steel grades are supplied for outdoor corrosive environments and marine equipment projects. Available surface finishes include zinc plating, black oxide, passivation and nickel plating, clients can select treatments based on corrosion resistance requirements and appearance matching needs of their end products.
Main Application Fields
Hex head sems screws fit a broad range of industrial scenarios. They are commonly adopted for automotive component assembly, new energy battery cabinet fixing, industrial machinery frame connection, electrical equipment enclosure installation and engineering machinery part fastening. The high torque tolerance makes them a preferred choice for structural fastening jobs that pan head fasteners cannot support steadily.
Customization Support
We support full customization services for hex head sems screws. Customizable items cover thread pitch, screw length, washer quantity combination, head size tolerance and special surface treatment. We accept small batch sample orders for client testing before mass production, and adjust production parameters flexibly according to client drawings and working condition feedback.
Company Introduction
YH Fastener is a professional manufacturer focusing on mass production of various sems screws and custom industrial fasteners. We own complete automated cold forging, thread rolling and surface treatment production lines, implement strict dimension tolerance inspection for every production batch to guarantee stable consistency between bulk orders. Our engineering team provides professional technical consultation for fastener selection and solution matching.
Inquiry Guidance
If you have demands for hex head sems screws, you may send your required specifications, material grade, surface treatment and estimated order quantity to us. Our sales team will reply with detailed quotation and lead time promptly, we also provide targeted fastening suggestions for your specific application scenarios.
FAQ
Q1: Can the washers fall off during transportation?
A1: Our pre‑assembly process fixes washers on the screw sh firmly, they will not drop off under normal logistics transportation and stacking conditions.
Q2: What is the regular tolerance range for thread?
A2: Standard thread tolerance adopts 6G grade to ensure stable matching with corresponding threaded holes.
Q3: Can I get free samples for testing?
A3: We provide sample service with freight collected, sample cost will be deducted when you place formal bulk orders.
Q4: What is the MOQ for customized hex head sems screws?
A4: The minimum order quantity depends on specification and material, we negotiate flexibly for different client project demands.