HP – PUMPS FOR WATER – JET - CUTTING

SOME SPECIAL FEATURES

HP – Pumps for water jet cutting have a long tradition. The basis was the manufacturing of catalyst injection pumps for ldPE – plants in the 60ths. When launching high pressure water jet cutting in the 70ths several new HP – pumps have been developed, based on different philosophies. Based on our long term experience with all kinds of high pressure pumps and high pressure applications, we have created in the beginning of the 90ths our water jet pumps, which have the following features:

• Easy maintenance
• User orientated design
• Easy integration in existing systems
• Simple controls
• Compact design

Easy Maintenance.
Only screwed connections are used in all HP – connections. Therefore all items much more easily can be removed and mounted as it is possible when using studs or other kinds of bolts. The inlet and outlet check valves are ready assembled with a connecting fitting. They can be removed as a complete set after the HP – pressure tube at the barrel outlet or the hoses at the inlet are removed. No valves are inside of the barrel. The valve sets are arranged in a valve body which directly is linked to the barrel with a left hand / right hand threaded nut. So the front seal ring, which is of a self sealing design, easily can be replaced, if this is necessary. The plunger sealing can be changed after the barrel has been screwed out of the end of the hydraulic cylinder.
HDS prefers to use commercial seal rings which easily can be bought around the corner if this is wanted. Special made seal systems are available also.

User orientated design.
HP – pressure pumps for water jet cutting are available in sizes from 5.5 to more than 55 KW with one intensifier. Redundant systems are available as well as twin intensifier units.
In order to keep maintenance time and cost as low as possible the plunger diameter was increased, in order to reduce the number of strokes per minute.

Easy integration in existing systems.
After having made the inlet and outlet connections and connected the pump to the electrical power supply the pump is ready for start up. The pump can be started and stopped from its control cabinet or remotely.
Special functions of the controller avoid an overshooting of the water pressure when the cutting nozzle is shut off. The pressure can be set remotely or directly at the control cabinet.

Simple controls.
The heart of the controller is an EASY – controller of Moeller. This controller can be programmed without any tools and external software. No gimmicks are included, but all necessary safety measurements have been taken care of. In case of emergency the machine will automatically shut off and the cause of the problem will be signaled by blinking lights.
All electrics and electronics can be maintained by local electricians. This will reduce down time, when ever this should occur at all.

Compact design.
As space has become one important issue in industry, the dimensions of the pumps have been reduced to a minimum. Every space in the sound proof housing is used, but all items remain easily accessible in case of maintenance. An oil-air cooler is mounted on top of the housing with its outlet upwards, so that no one is bothered by the air flow.

DESIGN CRITERIA FOR WATER JET CUTTING PUMPS

HP – pumps for water jet cutting are double acting intensifiers which are powered by an electro – hydraulic power unit. The oil pump is volume controlled. This allows, adapting the pressure for different cutting nozzle diameters. An attenuator reduces the pulsation of the intensifier to a minimum. An oil-air-cooler keeps the oil temperature even when the pump is running under full load below 50°C. A sound proof housing reduces the sound level of the pump to less than 8o dBa.
HP – pumps for water jet cutting are manufactured from 5,5 – 55 KW power input and a discharge volume of 0,5 – 5,5 l/min at a maximum discharge pressure of 400 MPa. Larger pumps are available on request. Pumps can be fitted out with a stand by intensifier or can have two synchronously acting intensifier. Redundant systems in different grades are also available.