Short answer
Code 61 and Code 62 are different series designations for hydraulic flange connections; the same nominal hose size does not show that they are interchangeable. The flange head, hole pattern, bolts, seal and the product's permissible operating conditions are checked together.
Technical explanation
In Parker's HPF description, ISO 6162-1 is associated with SAE J518 Code 61, and ISO 6162-2 with SAE J518 Code 62. These connection families should not be considered the same geometry even if the same nominal size is written. The standard name or trade code does not give a single working pressure for every diameter; the manufacturer's information for the relevant part and size is required. Flanges, seals and connection elements verified for one system should not be randomly mixed with another system.
Topic-specific checkpoints
| Item | Description |
|---|---|
| Series code | Code 61 / Code 62 distinction |
| Geometry | Flange head and hole centers |
| Hardware | Clamp, seal and bolts suited to the series |
| Limit | Actual product and size table |
How is it assessed in practice?
First check the series marking on the port or part and the machine drawing. If there is no marking, separately measure the outside diameter and thickness of the flange head, the center-to-center distance of opposite bolt holes and the seal groove. Compare the measurements only against the current drawing from the same manufacturer for the same series and nominal size; do not scale a dimension taken from another size or brand. An example decision sequence is: first the candidate series, then the four measurements, then the seal/clamp/bolt part codes and finally the pressure-temperature table of the actual product. Stop the assembly at a single discrepancy; this method does not replace the dimensional table.
Original editorial recommendation; not a clause of a standard.
Frequently asked questions
Can I fit a Code 62 part to a Code 61 port to make it stronger?
Interchanging between series cannot be done on that basis. The mating geometry and the approved assembly system must match.
Source coverage
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S095
ISO 6162-1:2012 ISO · accessed 2026-10-19 Public abstract: four-bolt flange connections, metric/inch fasteners; no pressure or torque tables imported
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S099
ISO 6162-2:2018 ISO · accessed 2026-10-19 Official bibliographic record and scope; not the full normative text
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S104
HPF - High Performance Flange Parker · accessed 2026-10-19 PDF page 2: The system; mapping of ISO 6162-1/Code 61 and ISO 6162-2/Code 62