Low pressure up to 19 bar
Nitto Kohki Pneumatic Solutions
Nitto Kohki low-pressure quick couplings up to 19 bar cover the most common operating pressure range of industrial compressed air systems. The series in this group range from micro couplings for small tube diameters through compact and cube-shaped designs to high-flow types (HI Cupla) and full-bore blow-off versions (Full Blow Cupla). All types connect plug and socket by simple push-in action and release by retracting the sleeve.
Micro CuplaMiniature quick coupling for small tube diameters
Small CuplaCompact coupling for restricted installation spaces
Compact CuplaShort-body coupling, space-saving design
Cube CuplaCube-shaped body for easy hose attachment
Super CuplaHigh-flow coupling, large nominal sizes
HI CuplaStandard quick coupling, wide nominal size range
HI Cupla 200Extended HI Cupla range, size 200
HI Cupla ACEImproved sleeve design for easier uncoupling
Full Blow CuplaFull-flow blow-off, aluminium/NBR, no internal stop
Line CuplaInline coupling for hose runs
Lever Lock CuplaLever locking to prevent accidental disconnection
For confined installation spaces, Micro Cupla, Small Cupla and Compact Cupla offer small dimensions. High-flow applications call for HI Cupla, Super Cupla or Full Blow Cupla. Lever Lock Cupla prevents accidental disconnection under vibration. Cube Cupla simplifies hose attachment through its cuboid body. For inline connections along a hose run without a side branch, Line Cupla is the appropriate choice.
Typical applications: Compressed air supply for pneumatic tools and machines in the up-to-19-bar range, flexible hose distribution systems in manufacturing, frequently changed compressed air connections at assembly stations and service points, and blow-off tool supplies where low coupling pressure drop maintains system efficiency.
Series in this category compared
Maximum working pressure is the first selection criterion. It decides the series, not the size: a low pressure coupling does not become high pressure capable by choosing a larger bore.
| Series | Max working pressure | Sizes | Shut-off type | Fluids | Body material | Catalogue page |
|---|---|---|---|---|---|---|
| LEVER LOCK CUPLA | 18 bar | Metal body: 3/4 inch to 4 inch. Plastic body: 3/4 inch, 1 inch, 1 1/2 inch, 2 inch, 3 inch. | Straight through | Water, Hydraulic oil, Air, Powder, Steam | Aluminum alloy (AL), Copper alloy (BR), Stainless steel (SUS), Polypropylene (PP) | 77 |
| FULL BLOW CUPLA | 15 bar | Thread and hose barb 1/4 inch, 3/8 inch, 1/2 inch. SN type for urethane hose: for dia. 6.5 mm x dia. 10 mm, dia. 8 mm x dia. 12 mm, dia. 8.5 mm x dia. 12.5 mm and dia. 11 mm x dia. 16 mm polyurethane hose. | One-way shut-off | Air | Aluminum alloy | 49 |
| HI CUPLA | 15 bar | Thread and hose barb 1/8 inch to 1 inch, 1/4 inch to 1 inch hose | One-way shut-off | Air, Water | Steel (Chrome plated), Brass, Stainless steel (SUS304) | 39 |
| HI CUPLA 200 | 15 bar | Thread and hose barb 1/4 inch, 3/8 inch, 1/2 inch. Tube barb (Tube fitter): Polyurethane tube outer dia. 6 +/-0.1, 8 +/-0.15, 10 +/-0.15; Polyamide tube outer dia. 6 +0.05/-0.08, 8 +0.05/-0.1, 10 +0.05/-0.1; Fluorine contained resin tube outer dia. 6 +/-0.07, 8 +/-0.07, 10 +/-0.07. | One-way shut-off | Air | Steel (Chrome plated) | 43 |
| HI CUPLA ACE | 15 bar | Thread and hose barb 1/4 inch, 3/8 inch; PN, SN, PNG and SNG types for ø5 mm x ø8 mm, ø6 mm x ø9 mm, ø6.5 mm x ø10 mm, ø8 mm x ø12 mm and ø8.5 mm x ø12.5 mm polyurethane hose | One-way shut-off | Air, Water | Engineering plastics (PBT, POM) | 61 |
| LINE CUPLA 200 | 15 bar | - | One-way shut-off | Air | Body: Aluminum alloy, CUPLA: Steel (chrome plated) | 57 |
| COMPACT CUPLA | 10 bar | Thread 1/8 inch; tube barb for ø4 x ø6 and ø6 x ø8 tube | Two-way shut-off | Air, Water | Brass, Stainless steel (SUS304) | 31 |
| CUBE CUPLA | 10 bar | 4 mm and 6 mm ID tube, 1/8 inch | Two-way shut-off, one-way shut-off or straight through, depending on the combination of valved and valveless socket and plug. | Air, Water | Polyacetal resin (POM) | 33 |
| MICRO CUPLA | 10 bar | Thread 1/8 inch, M5x0.8. Tube barb tube ID o3, o4. Tube barb (Tube fitter): polyurethane tube outside dia. o4 +/-0.1, o6 +/-0.1; polyamide tube outside dia. o4 +0.05/-0.08, o6 +0.05/-0.08; fluorine contained resin tube outside dia. o4 +/-0.05, o6 +/-0.07 | One-way shut-off | Air, Water (Tube Fitter type is unsuitable for water.) | CUPLA : Brass (Plated), CUPLA : Stainless steel (SUS304), Tube Fitter Part : Brass (Plated), Tube Fitter Part : Plastic, MICRO LINE CUPLA branch body : aluminum alloy | 23 |
| SMALL CUPLA | 10 bar | Thread 1/8 inch, 1/4 inch; Hose barb polyamide hose o4xo6, o4.5xo6, urethane hose o4xo6; Tube barb (Tube fitter) polyurethane tube OD o6 +/-0.1, o8 +/-0.15, polyamide tube OD o6 +0.05/-0.08, o8 +0.05/-0.1, fluorine contained resin tube OD o6 +/-0.07, o8 +/-0.07 | One-way shut-off | Air, Water (Tube Fitter type is unsuitable for water.) | CUPLA : Brass (Chrome plated), Tube Fitter Part : Brass (Nickel plated) , Plastic | 27 |
| SUPER CUPLA | 10 bar | Thread: 1/8 inch, 1/4 inch. Hose barb: 1/4 inch, urethane hose ø5 x ø8, ø6.5 x ø10. Tube barb (Tube fitter): outside dia. ø6 and ø8 | One-way shut-off | Air | CUPLA : Steel (Chrome plated), CUPLA : Aluminum alloy, Tube Fitter Part : Brass (Nickel plated), Tube Fitter Part : Plastic | 37 |
The four shut-off types
The shut-off type decides what happens on disconnection. It is the second criterion and depends on whether the line is under pressure when it is parted and how much fluid may escape.
Choosing a coupling in five steps
- Fix the fluid and the operating temperature, which gives the seal material.
- Determine the maximum working pressure, which gives the pressure class and the series.
- Choose the shut-off type: one-way, two-way, valveless or flat face.
- Fix the end connection and size: hose barb, male thread, female thread or tube fitter.
- Choose the body material for the fluid and the environment, then order plug and socket as a pair.
This page is based on the Nitto Kohki general catalogue Quick Connect Couplings C01en-b, 190 pages. The complete catalogue is available for download on this page.
