700R Cupla
High-Pressure up to 700 Bar
The Nitto Kohki 700R Cupla is a high-pressure quick coupling in steel with NBR seals, rated for operating pressures up to 700 bar. The range covers plugs (700R-3P, 700R-4P) and sockets (700R-3S, 700R-4S) in nominal sizes 3 and 4. Steel housings and hardened sealing elements ensure long-term operation under the extreme pressures found in hydraulic test benches and high-pressure water-jet systems.
| Type | Design | Nominal size | Material | Seal |
|---|---|---|---|---|
| 700R-3P | Plug | 3 | Steel | NBR |
| 700R-4P | Plug | 4 | Steel | NBR |
| 700R-3S | Socket | 3 | Steel | NBR |
| 700R-4S | Socket | 4 | Steel | NBR |
Typical applications: Hydraulic test benches and pressure-testing systems, high-pressure water-jet installations, high-pressure cleaning systems, hydraulic press connections, and laboratory rigs where lines must be changed frequently under high pressure.
Technical data from the manufacturer catalogue
| Series | 700R CUPLA |
|---|---|
| Body material | Special steel (Nickel plated) |
| Seal material | Nitrile rubber (NBR), Fluoro rubber (FKM) |
| Max working pressure | 68.6 MPa {700 kgf/cm2, 686 bar, 9950 PSI} |
| Working temperature | Nitrile rubber (NBR): -20 °C to +80 °C | Fluoro rubber (FKM): -20 °C to +180 °C |
| Valve structure | Two-way shut-off |
| Applicable fluids | Hydraulic oil |
| Vacuum service | 1.3 Pa {1x10-2 mmHg}: socket only not applicable, plug only not applicable, operational when connected. |
| Size range | Thread 3/8 inch, 1/2 inch |
| Catalogue page | C01en-b, 112 |
Operating principle
- Metal-touch valves use no rubber seal, and thus ensure excellent durability.
- Both socket and plug have metal touch automatic shut-off valves that prevent fluid spill out on disconnection.
- High pressure CUPLA for working pressures up to 68.6 MPa.
- For hydraulic pressure up to 68.6 MPa {700 kgf/cm2}.
All models of the series
P - Female thread
| Model | Coupling part | Application | Steel (g) | L | C | T | øH(WAF) | øøD |
|---|---|---|---|---|---|---|---|---|
| 700R-3P | Plug | R 3/8 | 210 | 54 | 18 | Rc 3/8 | 24 | (39.5) |
| 700R-4P | Plug | R 1/2 | 418 | 70 | 22 | Rc 1/2 | 27 | (50) |
S - Female thread
| Model | Coupling part | Application | Steel (g) | L | T | øH(WAF) | øøD |
|---|---|---|---|---|---|---|---|
| 700R-3S | Socket | R 3/8 | 270 | (73) | Rc 3/8 | 22 | (39.5) |
| 700R-4S | Socket | R 1/2 | 562 | (91) | Rc 1/2 | 27 | (50) |
Dimensions in millimetres. Values in brackets apply in the connected condition.
Legend: L = overall length; H = width across flats or outside dimension; D = socket outside diameter; A = hose barb length; C = sleeve dimension; T = thread or barb size; B = bore
Series comparison
| Series | Max working pressure | Size range | Valve structure | Applicable fluids |
|---|---|---|---|---|
| 210 CUPLA | 206 bar | 1/4 inch to 1 inch | Two-way shut-off | Hydraulic oil |
| HSP CUPLA | 206 bar | 1/4 inch, 3/8 inch, 1/2 inch, 3/4 inch, 1 inch, 1 1/4 inch, 1 1/2 inch, 2 inch | Two-way shut-off | Hydraulic oil |
| HYPER HSP CUPLA | 206 bar | 1/4 inch, 3/8 inch, 1/2 inch, 3/4 inch, 1 inch | Two-way shut-off | Hydraulic oil |
| HSU CUPLA | 210 bar | Thread 1/4 inch, 3/8 inch, 1/2 inch, 3/4 inch, 1 inch | Two-way shut-off | Water, Hydraulic oil, Gas |
| 280 CUPLA | 315 bar | Thread 1/4 inch, 3/8 inch, 1/2 inch, 3/4 inch, 1 inch | Two-way shut-off | Hydraulic oil |
| 350 CUPLA | 345 bar | Thread 1/4 inch, 3/8 inch, 1/2 inch, 3/4 inch, 1 inch, 1 1/4 inch, 1 1/2 inch | Two-way shut-off (Spill Reduction) | Hydraulic oil |
| 450B CUPLA | 441 bar | 3/8 inch | Two-way shut-off | Hydraulic oil |
| 700R CUPLA | 686 bar | Thread 3/8 inch, 1/2 inch | Two-way shut-off | Hydraulic oil |
Choose 700R CUPLA when the hydraulic line works above the pressure range of the sibling series: the highest rated peer here, 450B CUPLA, stops at 44.1 MPa {450 kgf/cm2}, while 700R CUPLA is rated up to 68.6 MPa {700 kgf/cm2}. All series in this group are two-way shut-off, so the pressure class and the available sizes 3/8 inch and 1/2 inch decide the choice. Where impulse pressure occurs in the line, 700R CUPLA must not be used.
Body and seal materials
| Body material |
|---|
| Special steel (Nickel plated) |
| Seal material | Mark | Working temperature | Remarks |
|---|---|---|---|
| Nitrile rubber | NBR | -20 °C to +80 °C | Standard material |
| Fluoro rubber | FKM | -20 °C to +180 °C | Made-to-order item |
Further catalogue data
| Note | Value |
|---|---|
| Pressure unit conversion | Working pressure 68.6 MPa, 700 kgf/cm2, 686 bar, 9950 PSI |
| Stand-alone leakage rate on either socket or plug | For 700R-3SP, 0.05 mL/min at 0.2 MPa {2 kgf/cm2}. For 700R-4SP, 0.5 mL/min at 0.3 MPa {3 kgf/cm2} |
| Maximum tightening torque | 3/8 inch 40 {408} Nm {kgf - cm}, 1/2 inch 85 {867} Nm {kgf - cm} |
| Flow direction | Fluid flow can be bi-directional when socket and plug are connected. |
| Minimum cross-sectional area | 700R-3SP 34 mm2, 700R-4SP 55 mm2 |
| Admixture of air on connection | 700R-3SP 1.0 mL, 700R-4SP 2.2 mL. May vary depending upon the usage conditions. |
| Working temperature range | The working temperature values are not legible in the supplied page text and are therefore not recorded. |
| Flow rate | Flow rate - pressure loss characteristics are given as a graph for 700R-3SP and 700R-4SP. Test conditions: fluid hydraulic oil, fluid viscosity 32x10-6 m2/s, density 0.87x103 kg/m3. Graph range 1 to 100 L/min against 0.01 to 1.0 MPa {0.1 to 10 kgf/cm2} pressure loss. |
Interchangeability and size groups
Socket and plug of different sizes cannot be connected.
Safety and application notes
- Do not use in an environment where there is impulse pressure.
- Before use, please be sure to read "Safety Guide" described at the end of this book and "Instruction Sheet" that comes with the products.
All technical data on this page is taken from the Nitto Kohki general catalogue Quick Connect Couplings C01en-b, page 112. The complete catalogue is available for download on this page.
