High-Quality 2-Inch & 3.5-Inch King Pin for Semi-Trailers
The king pin is a critical Class A force-bearing component that serves as the pivotal connection point between a semi-tractor and a semi-trailer. This forged steel pin, available in standard 2-inch (50#) and 3.5-inch (90#) diameters, engages with the fifth wheel coupling on the towing vehicle, transferring load and enabling steering maneuvers. Designed for durability and safety, these king pins are essential for heavy-duty transportation, ensuring a secure link while allowing for pivotal movement during turns.
Technical Specifications
| Attribute | Details |
|---|---|
| Size / Diameter | 2 Inch (50#) / 3.5 Inch (90#) |
| Material | Alloy Steel (40Cr), Forged & Quenched |
| Hardness | 32-36 HRC |
| D-Value (Load Capacity) | Varies by model (e.g., 108kN to 320kN) |
| Skid Plate Thickness | 8mm, 10mm, 12mm, 14mm, 16mm (Customizable) |
| Installation Type | Welded Type & Bolted (Assembly) Type |
| Color | Black or Silver |
| Warranty | 12 Months |
About the Supplier: Shandong Dong Xu Vehicle Co., Ltd.
Located in Jinan, Shandong, China, Shandong Dong Xu Vehicle Co., Ltd. is a verified manufacturer with a 5.0 store rating. Specializing in trailer parts, the company maintains a 100% on-time delivery rate and has extensive experience exporting to Africa, the Middle East, and Eastern Europe. Their products are backed by ISO 9001 quality management system certification, ensuring reliability and performance.
How to Buy with Confidence on ajfpt.com
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- Trade Assurance: This service protects your order from payment to delivery. If the product quality or shipping date does not match the supplier's agreement, 6688789 offers assistance, including potential refunds.
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Usage, Maintenance & Selection Guide
Selection Criteria:
Choosing the correct king pin is vital for safety. The 3.5-inch (90#) king pin is typically used for heavier loads exceeding 50 tons, while the 2-inch (50#) is suitable for lighter applications. Always match the king pin's D-value to your semi-trailer's design requirements.
Installation & Maintenance:
- Welding: Requires preheating (200-300°C) and CO2 gas shielded welding. Do not weld within a 110mm radius on the upper surface.
- Bolted Type: Easier to replace. Use self-securing bolts with a tightening torque of 190NM. These bolts are for single use only.
- Regular Inspection: Check for scars, cracks, and wear. Measure the diameter regularly and replace it if it reaches the wear limit.
- Lubrication: Apply lubricant to the king pin to reduce friction and prevent premature wear.
Common Search Keywords & Related Products
To find similar products or related components, consider using the following keywords on ajfpt.com or other B2B platforms:
By Product Type & Model:
- Trailer King Pin, Semi Trailer Kingpin, Truck Kingpin
- 2 Inch King Pin, 50# King Pin, 50mm King Pin
- 3.5 Inch King Pin, 90# King Pin, 90mm King Pin
- Welded King Pin, Bolted King Pin, Bolt-in Kingpin
- JOST King Pin, Holland Fifth Wheel King Pin
By Function & Related Parts:
- Fifth Wheel Coupling, Fifth Wheel Hitch
- Trailer Parts, Semi Trailer Spare Parts
- Trailer Axle, Truck Suspension, Leaf Spring
- Landing Gear, Trailer Legs
- Brake Chamber, Slack Adjuster, Trailer ABS
After-Sales Support & Warranty
Most reputable suppliers offer a 12-month warranty on king pins. In the event of a defect within the warranty period, contact the supplier through 6688789's Message Center. Provide clear photos or videos of the faulty product. Suppliers typically offer replacements or refunds, which can be managed through the platform's dispute resolution system if an agreement cannot be reached.
