Page 31 - MetalForming December 2016

Most waterjet-system manufacturers suggest cleaning the equipment after each use or at some specified interval. Repairs and maintenance procedures should be conducted in a clean environment.
as 1000 hr. Shops should regularly inspect pumps and the high-pressure plumbing for leaks. If a leak is found, fix it immediately—a leak allowed to continue at high pressure can quickly erode and damage the system and may not be repairable.
Tables with traction drives, specifi- cally designed for the wet, abrasive- laden waterjet environments, do not require lubricants. This enhances sys- tem reliability and reduces the time and money required for maintenance compared to other linear-drive sys- tems. Inspect table slats for wear at least once per month and replace weak or worn slats. Regularly rotating the slats to different locations on the table can greatly increase the life of the slats, as will the use of high-quality garnet.
Nozzle and Tank Maintenance
Ensure that the jewel orifice and nozzle body are properly aligned. And, after every 8 hr. of cutting, rotate the mixing tube 90 deg. This will avoid uneven wear, help minimize tapering and extend mixing-tube life.
We recommend the use of high-qual- ity abrasives, kept dry and free of debris. Dissolved solids can be removed from the inside edge of the nozzle’s jewel ori- fice by using an ultrasonic cleaner con- taining white vinegar. In addition, keep the diamond jewels clean to maintain optimal performance.
Abrasives and material particles should regularly be removed from the tank. A solids-removal system will do this automatically, eliminating down- time incurred during manual cleaning. The filter screen for the tank’s water outlet also requires cleaning.
Waterjet owners should test the water for quality and make sure it meets manufacturer specifications. Poor water quality and high water temperature can dramatically reduce the lifespan of critical components, such as high-pressure seals, high- pressure plumbing and nozzle assem- blies. A water chiller or water-treat- ment system may be required to overcome poor water quality and high temperature. MF
dimensions can result in the loss of business.
Preventive-maintenance software is available, and strongly recommend- ed. The software monitors operating conditions such as high-pressure plumbing, pumps, filters, abrasives and water-tank levels. It tracks operating hours of the components and will send alerts when components come due for maintenance or replacement.
Each waterjet system comes with recommended manufacturer mainte- nance procedures. It is vital for opera- tors to become familiar with the machine manual and routinely follow recommended maintenance steps. Fail- ure to properly clean and maintain the equipment can have a devastating effect on the product being cut and will lead to higher maintenance costs, as well as possible loss of business due to failed equipment.
Shop employees should complete equipment-manufacturer training before operating a waterjet system. Training addresses three areas: software programming, equipment operation and equipment maintenance. The level of training depends on the number of variables including operator skill level and mechanical aptitude. The com- plexity of the waterjet system and the amount of additional accessories may
impact the depth of the training and the time required. The average training program lasts three to five days.
Pump and Table Maintenance
Each style of waterjet system requires different maintenance protocols. A sys- tem that provides the same power at the nozzle using a lower-pressure pump will require less maintenance and replacement of high-pressure com- ponents than will a system using hyper- pressure. A pump may deliver 55,000 to 60,000 psi, but it may not be eco- nomical to run at that pressure. The higher the pressure the more wear you will experience to the seals, check valves, swivels, on/off valves, hoses and other components.
It is important to follow all equip- ment-manufacturer-prescribed main- tenance intervals and procedures to prevent unplanned downtime. A majority of waterjet-system manufac- turers suggest cleaning the equipment after each use or at some specified interval. Repairs and maintenance pro- cedures should be conducted in a clean environment.
Direct-drive pumps, compared to intensifier pumps, are simpler to understand, troubleshoot and main- tain. One style of pump can have a pre- ventive-maintenance interval of as long
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