Water jet cleaning system are commonly used when describing water as the tool to do surface preparation and pipe or tank cleaning,mostly in chemcal plant and ship hull . The use of water is a technique for cleaning surfaces, which relies solely on the energy and force of water striking a surface to acheive its cleaning effect. It do not need abrasive to mix the water to clean and cause the pollution .
Rust removal with water jet cleaning system
Flash rust :
When large areas are water jet cleaning, flash rusting which deminish the original surface standard may occur .Previous painting can be carried out. The degree of flash rusting depends on many factors, such as humidity level, temperature and the length of time the surface is exposed.
Degrees of flash rust :
Light flash rust : small quantities of light tan-brown rust will partially discolour the original steel surface. The discolouration may be evenly distributed, or in patches, but it will not be heavy enough to mark an object brushed against the areas.
Medium flash rust :
Alayer of light tan-brown rust will cover the original steel surface. This layer may be evenly distributed or in patches, but it will be heavy enough to easily mark objects brushed against the areas.
Heavy flash rust : a heavy layer of dark tan-brown rust will be completely covering the original surface. This layer will be evenly distributed and will easily mark objects brushed against the areas.
Removal of foreign elements with water jet cleaning system
The use of Water jet cleaning system has the advantage of removing oil and grease from the surface along with salt deposits. The grey, brown to black discoloration of corroded and pitted steel after waterblasting cannot be removed by further blasting. Studies shows that this thin film consists of mainly ferric oxide, which is an inert material. As it is tightly adherent, it does not present a serious contamination problem.
Surface condition after water jet cleaning system
water jet cleaning machine will not produce a surface profile as such. Weakend steel might erode, resulting in metal loss . But the surface profile exposed after blasting will have been produced by earlier surface preparation or corrosion.