hi guys, im currently running an old tecnocut waterjet machine from italy, our pump is getting old and requires alot of maintenance these days and i think its time for me to evaluate the market to see whats out there! Last week a customer told me at the fabtech trade show there is this new pump coming out which does not use hydraulic cylinders instead uses servo linear actuators, he reakons its gona be the way to go for a long time, im not sure on the company name, does anyone have any idea about the company or their product? I appreciate your help.

I think most waterjets use linear servo actuators to move the head, but I've never heard of a servo powered pump before. Please post the info if you find out.

The servo-driven pump is not a new one, a company in Japan (Sugino) has offered them for quite a number of years.  This same Japanese company still uses traditional Hydraulic Intensifiers for their continous, heavy-duty applications.  With that said though, the pump has some advantages....mainly it is quiet, compact, and runs about 20% more efficiently (only while stroking) than a traditional intensifier.  The down side is maintenance, cost, and some of the difficulties in handling variable pressure outputs.  At 55ksi, a 3/4" diameter plunger sees a force of appoximately 24,300 lbs.  Running a traditional servo motor at those loads on a continuous duty will likely present some issues.  We built two different prototypes of these pumps several years ago and it was novel while running.  In the end though, it was the intiial investment, the cost to replace the seals more often (greater wear due to larger shift spikes), as well as the short duty cycle of the servo components that eventually deemed it too unreliable for most purposes.

I seen the new Quantum at the recent Fabtech show and it looked totally different to the Sugino pump, which still looks quite large. In fact it looked more like an intensifier but without any hydraulics. Just being a layman it's hard to understand how a servo motor would have higher shift spikes than a simple hydraulic cylinder. Surely with the control you have over a servo motor you could do what ever you want, no?

thanks tim for your overview. Frank i found some good information on the servo pump through www.techniwaterjet.com.

A servo-driven system requires a high rotary inertia to create the high loads and cannot respond nearly as rapidly as a hydraulic system. It may be milliseconds, but that makes all the difference in the world. When you turn the On/off valve off there will be a larger spike in pressure and when you turn it on, there will be a greater dip, reducing the life of your fittings and tubing. There will be some increased fatigue in the pump also, but the brunt of the issues will be seen in other places.

-- Edited by waterjetgroup on Monday 7th of December 2009 08:14:53 AM