Waterjet Cutting Technology
A suitable water quality is the prerequisite for trouble-free and low-wear operation of every waterjet cutting machine.
An optimal water treatment pays for itself by saving maintenance and repair costs.
An inadequate raw water quality (or an inadequate water treatment!) increases the maintenance requirements and causes significant parts and repair costs. Even a water quality according to manufacturer's specifications can be improved in most cases.
In water hydraulics, there is hardly any other application where water is exposed to such high mechanical loads as in water-jet cutting.
At pressures of over 4000 bar and flow rates of multiple sound of speed, shortcomings in water quality become directly noticeable by decreasing lifetime of sealings and nozzles, damaged valves and cylinders, deposits at control valves and even bursting pipelines.ar.
An optimal water treatment requires a lot of experience and must be adapted to the individual raw water quality in every single case.
In many years of cooperation with manufacturers and users of waterjet cutting machines, we have identified eight main water quality related causes for disturbances and reduced equipment lifetime, and developed solutions for their elimination. Our 'firewall' concept enables us to treat raw waters of any quality according to requirements with one single, compact device which can be adapted or expanded anytime, should conditions change or new knowledge become available.
Primarily it is necessary to protect the waterjet cutting machine against the main causes of troubles:
Excess water hardness leads to deposits in the high pressure pump and its control elements, and in direct consequence to machine downtime.
The burning of fossile fuels raises the carbon dioxide concentration in the atmosphere. With the rainwater, a part of this carbon dioxide returns as 'acidic rain' and shortly afterwards can be found as carbonic acid in the ground water and subsequently in our mains water.
These gases, dissolved in the streaming water, cause a considerable load in pumps and pipelines through their pressure-dependent, permanently varying volume. Additionally, in the field of controlling devices (valves and the like), overheating and cavitation damages occur.
What is cavitation?
CavitationIn high-pressure systems, the throttling effect in narrowing flow channels (such as valves) causes pressure drops down to the extent of vacuum range. In these areas, the free, unbuffered carbonic acid outgases. In turbulent flow, gas bubbles grow. The back pressure at the water jet nozzle shatters these bubbles, causing micro-explosions. This physical effect is called cavitation and, in high-pressure pump technology, leads to a considerable decline of component lifetime according to the amount of excess gases.
Silicates, Iron and Chlorides
SilicatesSilicates, iron and iron oxydes build up particulate matter in the high-pressure area of the pump, whereas chlorides cause a punctual corrosive attack on the surfaces of the high-pressure cylinders and valves.
Particulate matter mainly leads to impacts at the nozzles. The edges at the water inlet of the nozzles are smashed, and the water jet fans out. Whilst destroyed nozzles can easily be exchanged, sludge of this matter tightens or blocks valves, causing leakages and cracks and thus leading to extended disruption of operations and spare parts costs.
CorrosionAlso, the punctual corrosive attack of chlorides in dynamically loaded components often marks the initial point of a crack. Additionally, during standstill periods with water evaporating in pumps and controls, the concentration of chlorides increases, leading to even heavier corrosive attacks especially in narrow openings (such as in the valve system) where rinse cycles with water or emulsions can not be realised.
16 years of experience... resulting in:
The FIREWALL for the Waterjet Cutting Machine!
With choice components perfectly supporting and complementing each other, we produce optimally balanced cutting water and eliminate the 8 main causes for damages at the high pressure components.
When compiling a water treatment for high pressure pumps, three factors must be respected:
- The composition of the raw water is very important and must be analysed first.
- The type of construction of the pump must be considered, that is whether a pressure intensifier pump or a direct driven pump is used.
- The pressure output of the pump is also important, because a 6000 bar pump reacts much more delicate to water quality deficiencies than a 3600 bar pump.
Direct drive pumps
In the smaller direct drive pumps, the water is intensely heated at the bypass (pressure control valve, pcv), thus creating troubles with deposits.
Low water hardness with low to medium contents of carbonic acid, silicates, iron and chlorides
Solution: Dosing station Liquidos II P&R (Plug and Run) and water additive Liquitech 207, a fast-acting water chemical with a cleaning additive effective against water hardness and other substances, against corrosion of stainless steels and crystallisation of silica (silicates).
Higher water hardness with medium to high contents of carbonic acid, silicates, iron and chlorides
Solution: Softening automat Zeomat + Dosing station Liquidos II P&R and water additive Liquitech 207.
The Zeomat softens the water, filtering even dissolved iron (like from well water) with its new ion exchanging granulate, and bonding carbonic acid while still working like any conventional softening automat.
In combination with the water additive Liquitech 207, protection against crystallisation of silicates is given up to contents of 20 mg/l.
Pressure intensifier pumps
Solution: new Procut III P&R (Plug and Run) with integrated Dosing station Liquidos II ( + depending on water hardness and other solutes: with or without Zeomat). Idealizes the cutting-water quality by intensively washing out gases, keeping up both operational reliability and simple handling and maintenance. Even installation and initial operation are finished with only a few steps.
Procut III P&R is generally offered related to 6000 bar technology, while in 4000 bar applications, it only applies depending on the content of carbonic acid and the utilized capacity of the cutting machine.
Reverse osmosis technology isn't first choice
All processes described above mostly do without elaborate, delicate and costly reverse osmosis technology that, above all, implicates considerable side-effects through large amounts of free, unbuffered carbonic acid in the cutting-water. Investing in reverse osmosis technology without the appropriate know-how usually leads to severe damages at the high-pressure pumps. Only in few extreme cases, this technology is required - but then categorically in combination with a PROCUT III for intensive washing-out of gases. To take coastly areas in northern spain as an example: after excessive use of ground water there, its level sank to such an extent that saline seawater followed up with its high chloride contents, irreversibly contaminating the drinking water reservoirs. In this and comparable cases (like pollution with oils or heavy metals or environmental sins the like), reverse osmosis technology is essential.
We provide analytic examination of your cutting-water quality.
- You receive from us a shipping case containing two sampling bottles and detailed sampling instructions.
- Send back the case with the water samples as quickly as possible to our laboratory for analysis.
- Then you receive an elaborate water analysis accompanied by an expertise explaining the appraisal of the analytic results to you and giving recommendations for water treatment. On request, we offer you an adequate system. The price for the analysis in the amount of 150,00 € will be fully offset in case of a following purchase order.