Frequently Asked Questions About Waterjets

General Questions

 

"Waterjet” is commonly used to reference both water-only water jet and abrasive water jet (abrasivejet) cutting. Water-only water jets cut with ultra-high pressure water alone. Abrasivejets cut with an abrasive material (usually garnet) that has been added to the water stream. Water-only waterjets can cut through softer materials such as food, rubber and foam. Abrasive waterjets are used to cut through harder materials such as plastic, composites, stone and metals.

A crankshaft or direct-drive style pump uses a crank to drive the waterjet pump’s plunger, while an intensifier uses a hydraulic cylinder to drive the plunger. Intensifier pumps cost somewhat more upfront, but pay for themselves over time with lower maintenance costs and longer service life. Jet Edge has customers who have logged more than 35,000 hours on waterjet intensifier pumps that are still going strong.

Precision Waterjet Pumps Brochure 

Virtually anything! Materials commonly cut with waterjet include rubber, foam, plastics, composites, stone, tile, metals, food, paper and much more. The only materials that cannot be cut with waterjet are tempered glass, diamonds and certain ceramics.

Jet Edge waterjet/abrasivejet cutting systems are controlled by PC-based motion control systems that can accept any CAD files.

Precision waterjet systems generally hold tolerances of +/-0.001" to 0.005" (0.025mm to 0.127mm). 70% of the industry cuts at +/-.010" or greater.

An operator with no experience whatsoever should be able to learn how to operate and maintain a waterjet cutting machine with as little as one week of training. New CAD/CAM nesting programs such as the IGEMS and SigmaNEST™ Companion software offered by Jet Edge make it possible for an operator with no programming experience to program the machine with only a few hours of training.

As with any machine tool, waterjet systems require routine maintenance to ensure lasting performance. With a day or two of training, a waterjet operator of average skill level should be able to perform basic maintenance tasks such as replacing nozzle parts and pump seals. When selecting a waterjet manufacturer, make sure they offer lifetime water jet maintenance training.

Jet Edge has cut metals as thick as 20 inches, including 15 inch titanium, with abrasive waterjet.

Jet Edge waterjet systems use a half gallon to approximately one gallon of water per minute for cutting, depending on the cutting head orifice size.  In addition, 3 to 5 gallons per minute are used to cool the waterjet pump.  The water can be recycled using a closed-looped system. Waste water usually is clean enough to filter and dispose of down a drain.

Before installing your Jet Edge water jet system, we recommend that you have a water quality analysis performed by a commercial company that specializes in water conditioning equipment. They can recommend the most suitable equipment for your specific water conditions. Inlet water should be treated for either the removal of hardness or the reduction in Total Disolved Solids (TDS). A water treatment producing TDS content of less than 0.5 ppm is not recommended since the aggressiveness of the purified water may damage the intensifier pump components. Treated water must have a pH value of 6 to 8.

  • If your water has low TDS (<100 ppm), it can be treated by softening alone.
  • If your water has moderate TDS (100-200 ppm), it can be treated by softening, deionizing (DI) or reverse osmosis (RO) equipment.
  • If your water has high TDS (>200 ppm), water quality is considered poor and should be treated with DI or RO equipment.
  • If your water has high silica concentration (>15 ppm), dual strong-base DI is recommended.

Abrasive waterjets use approximately 0.5 to 3 pounds (0.25 to 1.36 Kg) of abrasive per minute. Garnet abrasive is the most common abrasive used for abrasivejet cutting.  It is a natural material that can usually be disposed of in a landfill.  Some abrasive suppliers will take used garnet back for recycling.

Waterjet Garnet is a non-toxic natural substance that can be recycled for repeated use.  Spent water jet garnet usually can be disposed of in a landfill.  Some garnet suppliers offer recycling services.

A typical abrasivejet costs about $19-35 per hour to run per nozzle depending on horsepower, plus labor. This includes consumable parts, garnet, water and electricity. Utility costs vary depending on your location.

Virtually anything! Here are a just a few examples of what you can cut with your Jet Edge waterjet/abrasivejet cutting system.  Keep in mind that pure waterjets are used for cutting softer materials such as foam and rubber, while abrasive waterjets (abrasivejets) are used for cutting hard materials such as metals and stone.
 
Soft Rubber
Hard Rubber
Soft Gasket Material
Plastic
Foam
Nylon
Ceramics
Paper and Cardboard
Stone
Marble
Granite
Carbon Fiber
Reflective Metals
Graphite
Titanium
Aluminum
Hardened Tool Steel
Copper
Brass
Inconel
Hastalloy
Mild Steel
Stainless Steel
Exotic Materials
Composites
Glass
Carpet
Food Products
Diapers
Much, Much more

Waterjets can delaminate some materials such as fiberglass. In many cases, this can be prevented by low-pressure piercing or pre-piercing the material with a pneumatic drill prior to waterjettting. If this is a concern, ask your Jet Edge regional sales manager for a test cut on your material.

Waterjet cutting speed varies, depending on the material and thickness of the material, desired cut quality, water pressure, orifice/nozzle combinations, abrasive feedrate and other variables.

If you need a cutting speed for your application, please consult your Jet Edge regional sales manager.

 

There are many ways to increase productivity with waterjets.  You can add multiple cutting heads, you can buy an intensifier pump with higher horsepower, you can stack materials, and you can tightly nest parts to get more parts out of a sheet of material. The biggest gain in productivity in recent years has been the emergence of “hyper-pressure” waterjet intensifier pumps, such as Jet Edge's X-Stream waterjet pumps. These pumps can double the cutting speed for some materials.

This is by far the most frequently asked question!  Precision industrial waterjet systems can cost $150,000-$500,000+, depending on the table and pump size, accessory items and custom engineering needs.  Smaller budget systems cost around $80,000-$120,000. Mobile waterjet systems generally cost more than $100,000, depending on the system.  Remember, that seemingly simple mobile waterjet tool has to be powered by an ultra-high pressure pump and engineered to operate at pressures of 36,000 (2800 bar) or 55,000 psi. (3800 bar).  

For more details, please contact your Jet Edge regional sales manager.