Buying a Water Jet Machine? Precision Machine means Precision Parts

There are many companies that manufacture water jet machines or components. When purchasing a water jet cutting machine, be sure to look good at the x-y positioning precision of the manufacturer of the machine. The more accurate the hardware capability, the more accurate the parts you are able to quote, and thus cut. The physical positioning of the hardware, both while moving and while at rest is an important aspect of the final tolerance of a part, but it is not the whole story. Just be aware that some of the other aspects that affect part tolerance include but are not limited to the following: material thickness, material hardness, machine manufacturer cutting models, cutting speed (quality), nozzle settings, abrasive feed rate, machine calibrations, stack cutting, and operator skill. Other maintenance issues that affect part tolerance include wear and tear on the jewel, the focusing tube, the wear of the slat surfaces, and the need for pump pressure maintenance (rebuilds). The sales person representing a machine manufacturer will undoubtedly focus on the best tolerance scenarios. Buyer Beware!

Water Jet Cutting

Water Jet cutting services make use of a super high pressure stream of water that carries an abrasive grit. This abrasive mixes with the water through a venturi effect in what is commonly called the “focusing tube” just prior to cutting. This mixture of water and abrasive grit exit the focusing tube at speeds of approximately mach 2.5. Cutting pressures range between 45,000 to 90,000 psi for standard cutting models. For brittle, fragile, or delicate materials, piercing pressures range between 15,000 to 20,000 psi, and resume the higher cutting pressures when the pierce has been completed. This low pressure pierce is not true of all machines, and cutting models.