Mold Making
Nitto Kohki Pneumatic Solutions
Nitto Kohki provides two quick coupling series for mould-making and temperature-control circuit connections on injection moulding tools: the HW Cupla (hot-water couplings, brass, FKM) for cooling and temperature-control circuits with hot water, and the Mold Cupla (brass) covering cooling water, air and other media connections at injection mould parting lines. The 58-item range includes adapters for braided hoses (BH series) and high-temperature variants (K-01PM-HH, K-02PM-HH).
The Mold Cupla K series is available as plugs (PH, PM, PF, PML) and sockets (SH) in nominal sizes 01, 02 and 03. The brass body offers adequate corrosion resistance for cooling water service. The BH adapters (BH-90, BH-120, BH-150, BH-190) connect Mold Cupla ports to braided hydraulic hoses in hose sizes 3M, 4M and 6M.
| Series | Medium | Body material | Seal | Nominal sizes |
|---|---|---|---|---|
| HW Cupla (plug) | Hot water, temperature-control fluid | Brass | FKM | 2, 3, 4 (HW-xP-M) |
| HW Cupla (socket) | Hot water, temperature-control fluid | Brass | FKM | 2, 3, 4 (HW-xS-F) |
| Mold Cupla K (PH/PM/PF/PML) | Cooling water, compressed air | Brass | - | 01, 02, 03 |
| Mold Cupla K (SH) | Cooling water, compressed air | Brass | NBR | 02, 03 |
| BH adapter | Hose transition | Brass | - | 3M, 4M, 6M |
Typical applications: Temperature-control line connections on plastic injection mould tools, hot-water temperature-control circuits at elevated temperatures (HW Cupla, FKM), cooling water and compressed-air connections at mould parting planes (Mold Cupla K series), tool changers in injection moulding, and hose transitions to braided lines via BH adapters.
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 |
|---|---|---|---|---|---|---|
| HOT WATER CUPLA HW Type | 20 bar | Plug : R 1/4, R 3/8, R 1/2 / Socket : Rc 1/4, Rc 3/8, Rc 1/2 | Two-way shut-off | Water, Steam | Brass (Nickel plated) | 87 |
| MOLD CUPLA Series | 10 bar | Thread 1/8 inch, 1/4 inch, 3/8 inch; Hose barb for 1/4 inch and 3/8 inch hose / Braided hose o9 mm x o15 mm | One-way shut-off, Straight through | Water, Heated oil | Brass | 73 |
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.
