# SAE J518 4-Bolt Flange — Hydraulic and pipe connection type identification

For SAE J518 4-Bolt Flange, governing standard is SAE J518; region of origin is American Connections; thread type (tapered or parallel) is flange bolts; seat or flare angle is flat surface; seal method is The male is a flanged head with a groove for an O-ring and either split or captive flange halves and bolt holes which match the port. The seal is made where the O-ring is compressed between the flanged head and the flat surface of the port. The connection is held by threaded bolts, recorded from its source on 2026-08-13.

- **Connection type:** SAE J518 4-Bolt Flange _(verified: appears in the quote below)_
- **Governing standard:** SAE J518 _(verified: appears in the quote below)_
- **Region of origin:** American Connections _(our reading, not quoted from the source)_
- **Thread type (tapered or parallel):** flange bolts
- **Seat or flare angle:** flat surface _(verified: appears in the quote below)_
- **Seal method:** The male is a flanged head with a groove for an O-ring and either split or captive flange halves and bolt holes which match the port. The seal is made where the O-ring is compressed between the flanged head and the flat surface of the port. The connection is held by threaded bolts. _(verified: appears in the quote below)_
- **Interchangeability notes:** Excluding bolt sizes, SAE J518, JIS B 8363, ISO/DIS 6162 and DIN 20066 are interchangeable.

## What the source says

> SAE J518 4-Bolt Flange* There are two pressure ratings for these connections: Code 61 which is considered the standard series and Code 62 which is the 6000 PSI series. The design is the same for each series, yet the flange head diameters and bolt hole spacing are larger for the 6000 PSI high pressure Code 62 connection. The female port of the fitting is a smooth, un-threaded port with four bolt holes set in a rectangular pattern around the port. The male is a flanged head with a groove for an O-ring and either split or captive flange halves and bolt holes which match the port. The seal is made where the O-ring is compressed between the flanged head and the flat surface of the port. The connection is held by threaded bolts.

## Source

- https://brennaninc.com/connection-types/

Last verified: 2026-08-13. Review by: 2028-08-12.
Part of [Hydraulic and pipe connection type identification](https://referencesource.org/hydraulic-pipe-connection-types/).