Introduction to the King Pin 90.27.04 from Industrias Onyarbi
In the heavy transport and semi-trailer industry, the excellence of the coupling subassembly between the tractor and trailer is essential. A critical point in this system is the King Pin 90.27.04, manufactured by Industrias Onyarbi, whose function is essential for the operational and dynamic safety of the industrial vehicle. This part – often referred to simply as the ‘King Pin’ – must comply not only with demanding mechanical requirements but also with European approval standards. In this article, we will describe the King Pin 90.27.04 in detail: its use, quality, technical characteristics, approval in accordance with Regulation R55, and why it is a reliable choice for fleets, bodywork manufacturers and maintenance workshops.
What is the King Pin 90.27.04 and what is its function in commercial vehicles?
The King Pin 90.27.04 is a fifth wheel coupling pin for industrial vehicles – tractor units and semi-trailers – that require a secure and sturdy connection between the trailer and the tractor unit.
This King Pin is mounted on the top plate and is the axial point on which the fifth wheel rotates, transmitting traction, braking and turning forces. Its correct installation is critical for dynamic stability, road safety, the longevity of the assembly and the maintenance of the commercial vehicle.
When we refer to King Pin 90.27.04, we are referring to a specific product manufactured by us, Industrias Onyarbi, designed for a single hole (bolt-on) with 8 holes, according to our technical catalogue.
In practice, this king pin absorbs considerable forces: vertical forces, shear forces, torsional moments during turning, and traction/braking loads. Selecting the right king pin is key to ensuring optimal performance of commercial vehicles and preventing premature wear, vibrations, play, or even potentially critical failures.
Quality and design of the King Pin 90.27.04 from Industrias Onyarbi
The quality of a king pin such as our reference 90.27.04 must be evaluated in several aspects: material, heat treatment, tolerances, surface finish, assembly fit, dimensional control, and compliance with standards. Industrias Onyarbi guarantees that this component has been manufactured under strict quality procedures, with traceability of materials and appropriate testing.
– Materials and treatment: high-strength steels are used, specifically 42CrMo4, with heat treatments of hardening and tempering, ensuring adequate hardness and wear resistance.
– Finish and tolerances: the King Pin 90.27.04 has precise tolerances to ensure correct coupling to the plate, preventing slack that increases play or vibration fatigue.
– Assembly and fixing: reference 90.27.04 is designed for bolt-on assembly with 8 holes (bolt-on hole pattern), which facilitates installation and maintenance.
– Inspection and verification: At Industrias Onyarbi, the king pins have been approved in accordance with regulation R55.
Therefore, the King Pin 90.27.04 is not a low-cost component, but rather a part designed for demanding environments, in industrial vehicles that travel long distances, carry heavy loads and are subject to intensive use. This reliability results in less maintenance, a longer service life for the coupling, and greater safety for the carrier.
King Pin approval in accordance with Regulation (EU) R55
One of the key points is the approval of the King Pin 90.27.04 in accordance with Regulation (EU) R55, a European standard that regulates coupling devices between tractors and trailers (in particular fifth wheels, king pins and hitches) and compliance with which is mandatory to ensure lawful circulation and use in the European Union. Industrias Onyarbi’s King Pins ‘have been approved in accordance with Regulation 55’ with the approval codes: e955R01.6096, e955R01.6095, e955R01.6097 with loads d=180 kN / 200 kN.
This approval means that the King Pin 90.27.04 complies with load, fatigue, durability and safety tests according to the criteria defined in R55. This offers two major advantages:
1. European legal compliance for industrialists, trailer manufacturers, and fleet managers.
2. Guarantee that the component has passed tests verifying its performance under actual service conditions, which reinforces its technical acceptance.
Therefore, when installing a King Pin 90.27.04 approved according to R55, customers can rest assured that they are using a part that meets the highest technical requirements and is backed by recognised certification.
Applications in commercial vehicles and operational advantages
El King Pin 90.27.04 se emplea principalmente en la conexión entre tractora y remolque, en el sistema de quinta rueda. Las principales aplicaciones y ventajas operativas incluyen:
• Use in tractor units, semi-trailers and articulated units that require a robust coupling.
• Suitable for heavy loads and intensive use, thanks to its ‘8-hole bolt-on’ design that facilitates replacement during maintenance without the need for complex interventions.
• Improved operational safety: using an approved King Pin 90.27.04 minimises the risk of coupling failure, uneven wear or excessive play, which can lead to trailer instability, vibrations, chassis fatigue or even accidents.
• Longer service life for adjacent components: with a high-quality king pin, the fifth wheel, fifth wheel plate and other coupling elements suffer less irreversible stress, which extends the maintenance cycle and reduces operating costs.
• Ease of maintenance and replacement: reference 90.27.04 is clearly documented in the Industrias Onyarbi catalogue, making it easy to identify, order and replace.
Furthermore, as it is a component approved in accordance with Regulation R55, its use complies with European commercial vehicle industry standards, which benefits transport companies and manufacturers operating within the EU regulatory framework.
Conclusion: reliability and regulatory compliance
En resumen, el uso del King Pin 90.27.04 de Industrias Onyarbi es una solución técnica de alta calidad para vehículos industriales que requieren fiabilidad, seguridad y cumplimiento regulatorio. Este King Pin se distingue por su diseño robusto, sus materiales seleccionados, su acabado preciso, su montaje optimizado y, muy especialmente, por su homologación conforme al Reglamento (UE) R55, lo cual garantiza que cumple con los estrictos requisitos de la Unión Europea en materia de acoplamiento tractor-remolque.
For fleets operating in demanding environments, for semi-trailer manufacturers and for workshops wishing to offer certified components, the King Pin 90.27.04 is a safe bet.
