Bolt Hole Sleeve

Bolt hole sleeves (also known as bushings or spacers) are auxiliary components used with bolts and studs in automotive, motorcycle, and precision hardware assemblies. Installed around the fastener, they provide isolation, alignment, vibration damping, and gap adjustment between the fastener and the main component. These bolt hole sleeves are widely used in chassis, suspension, engine compartments, and frame connections to prevent wear, reduce loosening due to vibration, improve assembly accuracy, and enhance overall structural integrity and service life.

Products are manufactured according to ISO 3547 (bushings), GB/T 1176, and automotive standards, using materials suitable for specific applications: 45# carbon steel, heat-treated for high strength and wear resistance; SUS304 stainless steel, providing corrosion resistance in harsh conditions; H62 brass, offering good thermal conductivity and low friction; and oil-impregnated bearing alloys for self-lubrication. Surface treatments such as galvanizing, copper plating, or anodizing further enhance performance.

Our bolt hole sleeve series includes inner diameters from 5mm to 50mm, outer diameters from 8mm to 60mm, lengths from 10mm to 100mm, and wall thicknesses from 1.0mm to 5.0mm to accommodate various fastener sizes and clearances. Precision drawing or CNC turning ensures H7 grade inner and outer diameter accuracy and surface roughness Ra≤0.8μm for a tight and precise fit. We can customize special sleeves with stepped profiles, flanges, or grooves, as well as non-standard sizes, materials, and surface treatments to meet unique auxiliary fastening needs.

We maintain a stock of standard product products and offer fast delivery for custom orders. A rigorous quality control system includes dimensional accuracy, hardness, surface finish, and wear resistance testing to ensure consistent and reliable performance. With a comprehensive range of sizes, high-quality materials, and competitive wholesale prices, we offer a one-stop solution for tubing and provide expert selection advice and technical support to help customers improve assembly quality and product stability.