You're upgrading a machine. You install a powerful pump with a capacity of 100 liters per minute and huge cylinders to increase working force and speed. You start the system and... you're disappointed. The cylinders extend sluggishly, and after 15 minutes of operation, the oil is so hot you can't touch the reservoir. What went wrong?
Most likely, you've created a "bottleneck" in the system by forcing a powerful stream of oil through a too-small directional control valve (e.g., a standard monoblock or CETOP 03 manifold).
When large flows and heavy equipment are involved, you need heavy-duty solutions. BRhydraulic experts have taken a close look at manifold-mounted directional control valves in size CETOP 05 (NG10). Find out when you should say goodbye to smaller valves and why this standard is king in heavy industry.
1. CETOP 05 (NG10) – What kind of monster is this?
In our previous article, we discussed the popular CETOP 03 (NG6) standard, where flow channels are about 6 mm in diameter. It's great for medium-sized machines and flows around 40-80 l/min.
However, for heavy presses, large injection molding machines, or powerful construction machinery, that's definitely not enough. This is where CETOP 05 (according to ISO standard: NG10) comes in. The diameter of its main flow channels is about 10 mm. This seemingly small difference in millimeters makes a colossal difference in fluid physics!
NG10 directional control valves easily handle flows of around 120, or even 160 liters per minute, operating at powerful working pressures up to 315-350 bar.
2. The "bottleneck" syndrome: When NG6 is not enough?
What happens if you insist on pushing 120 liters of oil through a small CETOP 03 valve? The oil will flow, of course, but at the cost of huge energy losses. This phenomenon is called flow throttling.
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Drastic pressure drop (Delta P): Pushing a large amount of oil through a small opening means that before the valve, you have 200 bar of pressure, and after it, only, for example, 160 bar. You lose working force at the cylinder!
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Hydraulic furnace: Where does this lost energy go? It turns into heat. A too-small valve acts like a heater, rapidly "boiling" the oil, which leads to the destruction of seals and the pump itself.
If the pump in your system delivers more than 80 l/min, switching to a CETOP 05 (NG10) manifold and valves is an absolute technical necessity.
3. Heavy-duty, but the same "Lego" rules apply
The biggest advantage of CETOP 05 valves is that they share all the brilliant properties of their smaller sibling. They are manifold-mounted, have no screwed-in hoses, and are 100% standardized and interchangeable. An NG10 valve from BRhydraulic will fit perfectly in place of an old, burnt-out NG10 valve from Rexroth, Vickers, or Atos.
You unscrew four (this time much thicker) hex bolts, remove the powerful valve, install a new one, and you're done. A machine worth hundreds of thousands of zlotys is back in operation in 10 minutes.
Here, you can also use modular stacking. Under the main directional control valve, you can stack dedicated hydraulic locks, restrictors, or relief valves in NG10 size, building integrated, steel control blocks without a single gram of external piping.
Summary
Trying to save a few hundred zlotys by using too small valves for efficient pumps is a sure way to destroy the system through overheating. If you design agricultural, forestry, or industrial machinery with large flows, you must provide the oil with a sufficiently wide "highway."
At BRhydraulic, you will find professional CETOP 05 (NG10) manifold-mounted directional control valves, as well as matching subplates and modular valves. Contact us – we'll help you select the right flow to ensure your machine has maximum power without unnecessary oil heating!
