ISO 6162-2:2018

ISO 6162-2:2018 gives general and dimensional specifications for flanged heads, split flange clamps (FCS and FCSM), one-piece flange clamps (FC and FCM), ports and mounting surfaces applicable to four-screw, split and one-piece flange clamp type tube connectors and hose fittings for use at a pressure of 42 MPa (420 bar[1]). It also specifies the dimensions of the seals to be used, as well as the grooves that house the seals.
ISO 6162-2:2018 also recognizes the need to accommodate metric screw fasteners (type 1) (for DN 13 to DN 76), as well as to provide a means to use existing inch screw fasteners (type 2) (for DN 13 to DN 51).
These connections are intended for application in hydraulic systems on industrial and commercial products where it is desired to avoid the use of threaded connectors.
[1] 1 bar = 0,1 MPa = 105 Pa; 1 Pa = 1 N/m2.