Custom Heavy Duty Zipper Pin Box Supplier
A zipper pin box secures a metallic pin within a rectangular housing using interlocking zipper teeth that resist axial pull‑out and lateral shear. The assembly replaces traditional cotter pins or bolts in applications where rapid installation, high repeatability, and resistance to vibration are required.
Typical dimensional ranges accommodate pin diameters from 25 mm to 100 mm, with box heights between 30 mm and 150 mm and wall thicknesses from 6 mm to 20 mm. The zipper tooth pitch is commonly 5 mm, and the assembled unit can sustain axial loads up to 150 kN before permanent deformation, depending on material and heat treatment.
Material selection often starts with quenched and tempered alloy steels such as 4140 or 4340, delivering hardness levels of 38–45 HRC after tempering. For corrosive environments, austenitic stainless steels (e.g., 316L) or surface treatments like zinc‑nickel plating, nitriding, or PVD coatings are available to extend service life.
Customization focuses on pin length, flange diameter, zipper tooth profile (standard vs. reinforced with thicker root), and locking features such as spring‑loaded latches or secondary safety pins. Alignment tolerances are typically held to ±0.2 mm to ensure smooth engagement and prevent premature wear under cyclic loading.
In mining equipment, the zipper pin box retains hydraulic cylinder pins that experience shock loads and frequent reversal, reducing maintenance downtime compared with bolted solutions. Offshore drilling rigs benefit from corrosion‑resistant versions that withstand salt spray while maintaining quick‑release capability for riser connections. Material handling conveyors use the assembly to secure guide pins that must endure continuous vibration without loosening.
Quality control begins with coordinate‑measuring machine verification of critical dimensions, followed by Rockwell hardness checks on the pin and box surfaces. The zipper assembly undergoes tensile testing to validate load capacity, and magnetic particle inspection detects surface‑breaking defects. Each lot receives a unique traceability code linking raw material certificates to final inspection records.
- Pin diameter: 25 mm–100 mm (custom sizes available)
- Pin length: 50 mm–300 mm (according to application)
- Box height: 30 mm–150 mm
- Wall thickness: 6 mm–20 mm
- Zipper tooth material: alloy steel, stainless steel, or coated variants
- Surface finish: plain, zinc‑nickel, nitrided, or PVD
- Locking options: spring latch, safety pin, or integrated set screw
| Parameter | Standard Range | Customizable per Project |
|---|---|---|
| Pin Diameter | 25 mm–100 mm | Outside this range upon special quotation |
| Box Height | 30 mm–150 mm | Adjustable in 5 mm increments |
| Wall Thickness | 6 mm–20 mm | Thicker sections for high‑impact loads |
| Axial Load Capacity | Up to 150 kN (standard) | Higher capacities via material upgrade |
| Zipper Tooth Pitch | 5 mm (standard) | 3 mm or 7 mm available |
Frequently Asked Questions
Can dimensions be fully customized?
Yes. Pin diameter, length, box height, and wall thickness are adjusted according to the load path and installation constraints detailed in your drawing or sketch.
What information is required for a quotation?
Provide the pin size, expected axial and lateral loads, operating temperature range, exposure conditions (e.g., humidity, chemicals), and any required certifications or traceability levels.
Which materials are available for corrosive environments?
Austenitic stainless steels (316L, 304L) are standard. For harsher conditions, duplex grades or specialized coatings such as zinc‑nickel alloy or PVD can be supplied.
How is quality verified before shipment?
Each batch undergoes dimensional CMM inspection, hardness testing, tensile validation of the zipper assembly, and non‑destructive magnetic particle inspection. Documentation includes material certificates and inspection reports.
To discuss your specific heavy‑duty pin retention needs and receive a detailed technical proposal, please reach out using the contact form below. Our engineering team will review your requirements and propose a zipper pin box solution that meets load, environmental, and lifecycle criteria.
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