Energy storage, precision medical instruments and automated equipment have strict requirements on fastener dimensional accuracy, mechanical strength, anti-corrosion and insulation performance. Tiny quality defects may easily lead to equipment breakdown and safety hazards. CHILOK focuses on industrial fastener supply and builds standardized layered quality control procedures to strictly control the quality of every batch of metal and plastic fasteners.
All metal wires, nylon pellets and stainless steel bars are sampled and tested before warehousing. Metal raw materials are analyzed by spectrum analyzer to distinguish SUS304, SUS316 and grade 4.8-12.9 carbon steel, avoiding mixed materials. Nylon materials are tested for melt index, flame retardancy and UV resistance to select modified nylon for outdoor and electrical scenarios. Unqualified raw material batches will be returned directly without entering production to prevent rust, fracture and insulation failure caused by mismatched materials.
Inspection stations are arranged for stamping, thread rolling and injection molding. Samples are taken every hour to measure key dimensions such as thread outer diameter, head thickness and total length in accordance with GB and DIN tolerance standards. Precision tiny torx screws and ultra-thin nylon fasteners are checked by high-precision calipers and optical projectors to block defects like deformed heads and incomplete threads. Equipment parameters will be adjusted immediately once dimensional deviation occurs.
After galvanizing, Dacromet, black oxide and passivation treatment, special performance tests are carried out: 1. Salt spray test: Different test durations for inland and coastal projects, at least 1000 hours for SUS304 and over 2000 hours for SUS316 to record pitting and rust time; 2. Coating thickness test: Confirm anti-corrosion coating thickness to avoid thread assembly failure caused by too thick coating or short-term rust from thin coating; 3. Adhesion test: Ensure coating will not fall off under long-term vibration.
Test standards are classified by application industries: 1. High-strength bolts: Tensile and hardness test to guarantee anti-fracture performance under heavy load; 2. Insulated nylon fasteners: Withstand voltage and insulation test to prevent electric leakage for charging piles and control cabinets; 3. Medical precision screws: Non-magnetic and anti-corrosion test without metal precipitation for clean medical devices; 4. Outdoor PV fasteners: Extra anti-aging and UV resistance test for long-term outdoor exposure.
All products are visually inspected before packaging to remove defective goods with burrs and damaged threads. Each batch is marked with production code, raw material batch and test records. Test reports including material certificates, salt spray and hardness reports can be provided for customer incoming audit and project acceptance. For export fasteners, stricter tests are implemented to meet overseas inspection standards.
CHILOK keeps abundant stock of standard fasteners and accepts custom non-standard parts, including high-strength hex bolts, SUS304/SUS316 screws, security torx screws, insulated nylon hex screws and PCB spacers. We support R&D sampling, small-batch trial production and mass project orders. Supported by stable raw material supply and standardized inspection system, we continuously supply qualified fasteners for automation equipment, new energy vehicles, PV energy storage and medical testing equipment manufacturers.