Why Does Water Quality Matter?
A waterjet cutting system utilizes a mixture of water and abrasive (or in some cases, water only) to cut through workpieces by rapidly eroding the material. Because water plays such a significant role in the operation of these machines, it is important that the condition of the water is optimized in order to maximize both the efficiency of the waterjet and the longevity of its components. Low quality water can have a negative impact on operational/maintenance costs through the unnecessary wear of consumable parts. Water that is considered low quality can contain a number of different particles that act as an abrasive, wearing down the machine’s critical components. This will eventually increase overall consumables costs, decreasing profitability and detracting from your bottom line. It is important to test the quality of your water supply before the installation of a waterjet cutting system to avoid unnecessary harm to the machine and its parts. The majority of waterjet owners will not require a water treatment system, but for those that do, a small investment now can save major dollars (and headaches) down the road.
Determining Water Quality
For the most accurate results, water quality tests should be performed by a trained professional. Fortunately, many water treatment facilities will conduct these tests free of charge, and generally take no more than ten minutes total. Once the test is complete, take a look at the results. There are four measurements that need to be analyzed: the pH level, the SiO2 content, and the TDS and TSS concentrations.
||The ideal pH level of a waterjet’s water supply is between 6.0 and 8.0. Water that is outside of this range will not be suitable for cutting.
||SiO2 refers to the silica content of the water. The silica content must be lower than 15 parts per million (ppm). If over 15 ppm, deionization of the water will be necessary. Contact your waterjet manufacturer for information on deionization.
||TSS stands for total suspended solids. This is the number of small particles that are not fully dissolved in the water supply. If the level of TSS is determined to be too high, a filter should be installed in the pump to remove the solids. Most pumps include filters for this reason, but check with the pump manufacturer before operation to prevent damage to your machine.
||TDS are molecular particles including elements such as magnesium or calcium that can cause damage to the machine’s consumables, especially within the high-pressure pump. If a water supply is found to have a TDS level over a certain threshold, a water treatment system must be implemented.
Generally, a TDS level of less than 100 ppm is considered low, from 100 to 200 ppm is considered moderate, and anything about 200 ppm is considered high. The level of TDS in your water supply will determine the type of treatment necessary. For those with low levels of TDS, treatment with a simple water softener often will suffice. However, be careful not to purify the water too much – a TDS level lower than 50 ppm can actually cause damage to stainless steel parts.
For those with a moderate level of TDS, either a water softener or a DI (Deionization) system can be used to treat the water supply. Contact your waterjet manufacturer for the recommended method of treatment.
A TDS level above 200 ppm will require the installation of a reverse osmosis system. Reverse osmosis will continuously remove dissolved solids from the water supply until the TDS level is within an acceptable range for waterjet cutting. WARDJet offers reverse osmosis systems that can be fit to most brands of waterjet cutting systems.
Even if the initial water quality test results indicate that no water treatment is needed, it is recommended to periodically test your water supply. Certain conditions can change over time, resulting in varying TDS and TSS levels.
For more information on water quality testing and treatment options, contact WARDJet at 330-677-9100 or fill out our contact form.