Because metals are susceptible to corrosion in the marine environment, they are mainly affected by factors such as seawater temperature, salinity, marine atmospheric temperature and humidity. These factors will electrochemically corrode steel materials. In order to prevent this corrosion, the deck needs to be regularly rusted and painted.
Ultra-high pressure water jet rust removal is another common rust removal method. The principle is to pressurize ordinary water to an ultra-high pressure state through a booster device, and use the impact of ultra-high pressure water jets on the surface of the ship plate. When the impact energy of the water flow is greater than the adhesion of rust to the steel matrix, the rust layer is destroyed and the oil on the surface of the hull is removed, thereby achieving the purpose of rust removal and cleaning.
The ultra-high pressure water jet rust removal process is to pressurize ordinary water to 2000-3000 bar, and transport the ultra-high pressure operating medium to the terminal operating unit through a high-pressure resistant pipeline transportation system made of special materials. The end-acting system adjusts the ultra-high pressure water jet nozzle to apply ultra-high pressure water of different flow, angle and speed to the working surface, so as to remove rust and paint.
Ultra-high pressure water jet can completely clean the surface of the steel plate, forming a very clean metal surface with trace metal oxides. There are many defects in the microstructure of the steel plate surface after sandblasting, forming deformation holes, as well as torn and broken metal, ore particles and salt residues. The holes that originally existed on the surface can be clearly seen, but the inside is clean and there is no residue of other substances.
Used in ship deck rust removal, the ultra-high pressure cleaning machine used has a working pressure of 2200-3000bar, a working flow of 30L/min, and a deck rust removal efficiency of 20-30㎡/h, which is 3-4 times that of traditional manual sandblasting rust removal. The unit area cost of manual sandblasting is 39.07 yuan. The main cost is the cost of ore, accounting for nearly 60%. The unit area cost of the new process ultra-high pressure water operation is 24.66 yuan. Electricity costs are the main cost. In terms of unit variable costs of the two processes, the ultra-high pressure water rust removal process is superior to the traditional dry sandblasting process.
For the paint and rust removal of ship decks, Guangyuan Cleaning Equipment GYB38/2500 ultra-high pressure hydro blasting machine has an operating pressure of up to 2500bar and a flow rate of 38L/min. It uses a 250kw motor as the power source. The high-pressure pump is a WOMA three-piston pump imported from Germany. The pump combines the working intensity and durability of stable loads and has a good reputation in the industry.
Guangyuan Cleaning Equipment GYB38/2500 ultra-high pressure hydro jetting machine uses a high-strength special stainless steel pump head. The specially treated stainless steel linear valve group greatly enhances the service life of the valve body. Even if all valves are worn, they can be repaired by on-site fine grinding or surface grinding; the plunger is made of high-strength alloy stainless steel nitriding heat treatment and can withstand a continuous working pressure of more than 2500bar; the above characteristics ensure that the equipment can still work normally under harsh conditions. It is mainly used in road zebra crossing removal, box cleaning, hull rust removal and other fields.
From the above conclusions, it can be concluded that the ultra-high pressure water rust removal process for ships actually has obvious advantages over the dry sandblasting rust removal process in terms of operation quality, construction efficiency, variable costs, environmental protection and occupational health. In addition, ultra-high pressure water rust removal can completely replace traditional sandblasting rust removal for daily maintenance, voyage repair and factory maintenance of ship hulls.
