ISO 16028 standard Flush-face type, quick-action couplings for use at pressures of 20 MPa (200 bar) to 31,5 MPa (315 bar)

ISO 16028 specifies the interface dimensions for interchangeability and specifies the performance requirements for the hydraulic, flush-face type, quick-action couplings for use at pressures of 20 MPa (200 bar) to 31,5 MPa (315 bar), depending upon the coupling size.

Couplings in accordance with this International Standard are not designed to connect or disconnect under pressure.

Couplings in accordance with this International Standard provide for automatic sealing of the fluid pressure on the upstream side and on the downstream side when the coupling is disconnected.

In hydraulic fluid power systems, power is transmitted and controlled through a liquid under pressure within an enclosed circuit. Quick-action couplings are used to join or separate quickly fluid conductor lines, without the use of tools or special devices.

ISO 16028 standard – Dimensional requirements

ISO 16028 Standard Flat Face Quick Coupling Dimensional Requirements
Body Size
mm
Body Size
inch
A B C D F H J L
min. max. min. max. min. max. max. min. max. min. ±0.0025
6.3 1/4" 20.50 16.10 16.20 13.85 14.05 9,70 9,75 0,6 5,70 5,80 11,56 3,175
10 3/8" 24.10 19.66 19.79 17.53 17.73 12,65 12,70 0,6 4,68 4,86 16,25 3,175
12.5 1/2" 30.15 24.45 24.58 21,90 22. 10 15,62 15,70 0,7 9,75 9,95 17,35 3,969
16 5/8" 32.65 26.95 27.08 24,40 24,60 17,62 17,70 0,7 9,75 9,95 17,35 3,969
19 3/4" 36.68 29.87 30.00 26,80 27,00 20,67 20,75 0,9 11,30 11,50 23,20 4,7625
25 1" 44.85 35.94 36.07 31,90 32,10 23,67 23,75 1, 1 10,80 11,00 23,20 6,350
Body Size
mm
Body Size
inch
M N R T U K Q
min. min. max. max. min. max. min. max. min. max. min. max.
6.3 1/4" 10.80 0,18 0,33 7,65 20,70 20,80 0,25 0,75 9,55 9,60 13,85 13,95
10 3/8" 15.60 0,25 0,41 9,65 23 ,24 23,34 0,25 1,15 12,50 12,57 18, 11 18,21
12.5 1/2" 16,90 0,25 0,41 10,40 30,40 30,50 0,5 1 15,51 15,58 20,30 20,40
16 5/8" 17,50 0,30 0,46 10,50 32,90 33,00 0,5 1 17,48 17,55 20,30 20,40
19 3/4" 21,50 0,30 0,46 11,25 38,00 38,10 0,5 1 20,48 20,55 27,30 27,40
25 1" 22,60 0,43 0,58 13,05 45,25 45,35 0,75 1,25 23,48 23 ,55 29,85 29,95

ISO 16028 standard – Performance Requirements

Characteristic 1/4" 3/8" 1/2" 5/8" 3/4" 1"
Rated operating pressure,
in accordance with
ISO 4399
31,5 MPa25MPa 25MPa25MPa 25MPa20MPa
Minimum burst pressure 126 MPa 100 MPa 100 MPa 100 MPa 100 MPa 8OMPa
Rated flow 12 1/min 23 1/min 45 1/min 74 1/min 100 1/min 189 1/min
Maximum pressure drop
at rated flow
1 bar 1 bar 1 bar 1 bar 1 bar 1 bar
Rated surge flow 36 1/min 69 1/min 135 1/min 222 1/min 300 1/min 567 1/min
Maximum fluid loss per
disconnect
0,02 ml0,035 ml 0,07 ml0,1 ml 0,15 ml0,25 ml