ISO 5692-2:2002

Overview

ISO 5692-2:2002 defines requirements for the coupling ring 40 with socket used on agricultural towed vehicles. The standard specifies the 40 mm ring inside diameter for coupling with the drawbar coupling described in ISO 6489-2 and sets limits for vertical static and dynamic horizontal loads to ensure safe towing performance and the necessary horizontal and vertical rotation angles.

Key Topics

• Dimensions and shapes: The coupling ring is produced in two shapes (A - welding end, B - flange end). Detailed dimensional requirements and tolerances are to be selected in accordance with ISO 2768-1 and ISO 286-1 where not explicitly specified.
• Ring and socket materials: Sockets are specified as CT ISO 683-1 42CrMo4 steel. The ring material for weldable versions is chosen by the manufacturer, with welding procedures provided.
• Load limits: Applicable to couplings with vertical static load not exceeding 2 000 kg and a dynamic horizontal load not exceeding a D value of 120 kN (see ISO 6489-2 for D definition).
• Welding and hardness control: Welding procedures must limit hardness increase at weld contact surfaces to no more than 300 HV30; preheating to approximately 250 °C is indicated as an example measure.
• Socket integrity: Sockets shall not be welded or slotted and must be fastened so they cannot move during travel.
• Testing and marking: Ring shapes A and B must be inspected for cracks using a test procedure chosen by the manufacturer. The ring must bear the ISO 5692-2 identification and the manufacturer's mark in a durable, legible form.
• Designation examples: e.g., Coupling ring [ISO 5692-2](/search?q=ISO%205692-2)-A-40 and Socket [ISO 5692-2](/search?q=ISO%205692-2)-40.

Applications

ISO 5692-2:2002 is intended for manufacturers, specifiers and maintenance teams working with agricultural tractors and towed implements. Practical benefits include:

• Interoperability: Ensures compatibility with drawbar couplings per ISO 6489-2 for predictable fit and rotation.
• Safety and reliability: Defined load limits and material specifications reduce risk of coupling failure under typical agricultural operating conditions.
• Traceability and compliance: Durable marking and standardized designation help fleet owners and service personnel identify approved components quickly.
• Design guidance: Provides manufacturers with welding and hardness control guidance to avoid brittle zones and ensure joint integrity.

Related Standards

• ISO 6489-2 - Drawbar coupling 40 dimensions and D value definition
• ISO 683-1 - Heat-treatable and alloy steels (reference for 42CrMo4)
• ISO 2768-1 - General tolerances for linear and angular dimensions
• ISO 286-1 - Limits and fits

Note: ISO 5692 covers mechanical connections on towed vehicles; hitch-rings are identified as the subject of a future Part 1 to ISO 5692. For specific design or testing procedures beyond this summary, consult the full ISO 5692-2:2002 text and the referenced standards.