I recognize, there are Boiler feed pumps Suppliers. But if either of these items are a problem, then a butterfly valve is a only choice left. If you know of the hydraulic machine OEM who has this kind of empirical data, I would love to hear about it. And the way bad can that be? Well as mysterious, I can think of a good deal of applications where butterfly valves are widely-used as pump intake isolation valves. I don’t think I’ve ever seen a pump taken at a large hydraulic excavator that didn’t have a minimum of some cavitation erosion damage. Whenever I've come across this problem before, arranging the outlet plumbing that will effect a head of petrol above the pump (even a few inches) has solved the challenge. Probably, always purge the intake distinct air. If appropriate, consider turning the pump personally (gear-type only) with the outlet vented to ensure it isn't air bound. In case safe to do so, bleed the outlet on start-up to be sure the pump is displacing essential oil (and not spinning in an air-lock) Of course , if safe to do so, bleed the outlet on start-up to be sure the pump is displacing acrylic (and not spinning in a great air-lock). While it's unlikely the brain of oil has much influence for the vanes contacting the cam wedding band, it is plausible that arranging the plumbing like this ensures the pump fills itself with oil and is particularly then able to displace (or possibly compress) any air in it's outlet line. Spinning the gears without a strong uninterrupted oil supply will cause metal-to-metal contact between critical parts from the pump, which are designed running on a hydrodynamic film with oil
