What is high-pressure jet cleaning technology?

High-pressure water jet cleaning technology: In recent years, high-pressure water jet cleaning technology has developed rapidly and is widely used in industries such as petroleum, chemicals, power generation, and metallurgy. It can be used to clean containers such as autoclaves, reactors, cooling towers, storage tanks, and tank trucks ； It can also be used to clean various equipment, pipes, gas pipelines, and heat exchangers ； It can also be used to clean the various deposits on ships, such as marine organisms, scale, rust, various coatings, concrete, resin layers, pigments, rubber, gypsum, plastics, etc., and it delivers excellent cleaning results. High-pressure water jets have no impact on the environment, are efficient, and can easily meet cleaning requirements. 1. Principle and characteristics of high-pressure water jet cleaning. The principle of high-pressure water jet cleaning involves using a high-pressure pump to generate high-pressure water, which is then sent through pipes to a nozzle; there, the high-pressure water with low flow rate is converted into a low-pressure jet with high flow rate ； Then, the jet acts continuously on the surface to be cleaned with its high impact kinetic energy, thereby causing the dirt to fall off and achieving the cleaning purpose. Compared with traditional water jet cleaning, mechanical cleaning, and chemical cleaning, high-pressure water jet cleaning has the following advantages: 1) If an appropriate pressure level is selected, high-pressure water jet cleaning will not damage the substrate of the equipment being cleaned ； 2) High-pressure water jet cleaning involves using ordinary tap water under high pressure for cleaning; therefore, it does not pollute the environment, does not corrode equipment, causes no mechanical damage, offers high cleaning efficiency, saves energy, and can also remove special types of deposits that are difficult or impossible to remove through chemical cleaning ； 3) The washed equipment and parts cannot be subjected to cleaning treatment ； 4) Can be used for cleaning in harsh environments ； 5) Easy to mechanize and automate, and suitable for digital programming ； 6) Saves energy, offers high cleaning efficiency, and has low costs. 2. Structure of the high-pressure water jet cleaning device: The high-pressure water jet cleaning device, also known as a high-pressure water jet cleaner, is mainly composed of a high-pressure piston pump, a power unit, nozzles, high-pressure hoses, and various working accessories. 3. Determination of several key parameters during high-pressure water jet cleaning 1) Determination of operating pressure: The operating pressure for high-pressure water jet cleaning should be selected appropriately based on the properties of the scale. Pressure levels for high-pressure water jet cleaning: Low pressure, Medium pressure – 0.5~20 Mpa; 20~70 Mpa; High pressure, Ultra-high pressure – 140~400 Mpa; >400 Mpa. The commonly used pressure range for high-pressure water jet cleaning is 2~35 Mpa, with a water flow rate of 20~100 L/min. Within this range, the power consumption is 3~15 KW ； Most cleaning tasks can be carried out using water jets with a pressure of up to 70 Mpa ； Only a very small number of slagging operations require 270 Mpa. The comparison between delamination materials and pressure is as follows: Comparison of Delamination Materials and Pressure. Pressure/Mpa: 10, 21, 32, 42–70. Sediment, loose rock layers. Delamination materials: Mild ship dirt, mild fuel oil residues, aluminum radiators and housings. Loose concrete, common marine organisms, sand, gravel, and mud layers, mild oxidation layers on hot-rolled steel ingots, loose paint layers and rust. Concrete in pipes, marine biofilm, cast iron components, removal of adhesive from runways, light-base limestone, gravel layers, tar deposits, common petrochemical scale layers: 70–105. Cutting and removal of paint layers from concrete, limestone, large amounts of oxidized scale on hot-rolled steel, silica-based cores, combustion deposits, common petrochemical scale layers: 105–210. Granite, marble, limestone, epoxy coatings on ships, lead plates, aluminum plates, rubber, etc.; cutting. High-pressure water jet cleaning for frozen foods. Information on cleaning equipment pressure and flow rate. Treatment services include pipe descaling, sewer systems, oil well casings, grease and oil stains, oil tanks and tankers, shell-and-tube evaporators, boilers. Rust removal from steel materials and mechanical parts, jet cleaning. **Waste disposal. Solid propellants for rockets. 2) Determination of actual flow rate: The actual flow rate during spraying generally depends on the original rated flow rate: U=√2P/ρ, where U is the flow rate, in m/s ； P is the working pressure, in Mpa; ρ is the fluid density, in kg/m³. 3) The impact force acting on the load surface is determined as follows: F = 2.655×10^-4Ap^1.5. This is an empirical formula for calculating the impact force F exerted on a flat surface when a continuous jet strikes it perpendicularly. Here, F represents the impact force acting on the load surface, in N ； A is the cross-sectional area of the nozzle, in m² ； ρ is the operating pressure, in Mpa. 4) Determination of nozzle distance The nozzle distance refers to the distance from the nozzle to the surface to be cleaned, and its value has a significant impact on the quality of cleaning. As the distance of jetting increases, the degree of diffusion of the jet onto the surface to be cleaned increases, which in turn leads to greater loss of jet power ； As the spraying distance decreases, the descaling area per unit time also decreases. Therefore, either an excessively large or excessively small spraying distance will reduce the cleaning efficiency. Experiments have shown that for cleaning oils and greases on the surface of ordinary machinery, an injection distance in the range of (150–300) D is optimal, where D is the outlet diameter of the nozzle. 5) Determination of the incident angle: Based on empirical data, an incident angle of 17° is appropriate when cleaning oily surfaces. 4. Application examples of high-pressure water jet cleaning: High-pressure water jet cleaning technology is widely used in various industries for cleaning a range of chemical containers, heat exchangers, condensers, pipes, tube bundles, as well as for tasks such as coking removal, scale removal, rust removal, and hydraulic cleaning. For the cleaning of heat exchange equipment in foreign petrochemical companies, 80% use high-pressure water jet cleaning, while 10%–20% use chemical cleaning. High-pressure water jet cleaning achieves a quality comparable to steam cleaning, but with a 10%~40% increase in efficiency, enabling safe and environmentally friendly operation without the use of fire, toxins, or harmful substances. Storage tanks are process equipment that are widely used in petrochemical plants, come in various types and specifications, and can store different kinds of media; for example, storage tanks for synthetic rubber latex require regular cleaning. In the past, it was cleared using manual shovels, clearing a few square meters per day. High-pressure water jet cleaning is used: a high-pressure water generator with a pressure of 50 Mpa and a flow rate of 100 L/min, along with 2–3 single-nozzle spray guns. It is possible to clean one glue tank in 10 hours, which increases efficiency by more than ten times. When the tube heat exchanger is completely blocked, chemical cleaning cannot be carried out. Using steel picks for manual mechanical cleaning is inefficient and can also damage the pipe fittings. The high-pressure water jet cleaning technique is employed, with a pressure of 70–100 Mpa and a water flow rate of 84 L/min; the cleaning is completed within over ten hours. 1) Example of cleaning the inner wall of the ash conveyance pipe in a power plant. Baosteel’s own power plant is a thermal power plant that uses coal powder as its main fuel. To transport the fly ash sludge centrally to the ash dump on the Yangtze River bank, a pumping station has been installed, along with three 2500-m-long wet ash conveyance pipes that are used in rotation. Wet ash is transported by water pressure; during the production process, structures form on the inner walls due to the process materials and water system, with a thickness of 20–60 mm. The wet ash is gray in color, has a layered structure, is hard and dense, and resembles tile tubes, which interferes with normal operation. In the past, under the guidance of Japanese experts, pressure acid cleaning, soaking, degassing, and cyclic chemical cleaning were employed for the entire pipe system. Due to the complex layout of the air and pipeline systems, as well as the need to cross bridges and roads and make various turns, the pipelines have uneven heights, which makes it difficult for the pickling solution to fill the entire lumen, resulting in incomplete pickling. High-pressure water jet cleaning is now used, with a pressure of 100 Mpa, a flow rate of 64 L/min, and a power output of 139 kW. Cleaning in segments of 30m each yields good results. 2) Examples of heat exchanger cleaning: Example from Shaanxi Kelly Cleaning Co., Ltd.: More than a dozen tubular carbon steel heat exchangers in a factory were clogged by scale and sediment, and high-pressure water jet technology was used for their cleaning. The cleaning area is nearly 5,000 m², the cleaning pressure ranges from 60 to 80 Mpa, and the cleaning time for each unit is 70 to 100 hours. The cleaning effect reveals a metallic shine on the surface, with no damage. 12 heat exchangers in a pyrolysis workshop at a chemical plant in Beijing, 8 heat exchangers in a polystyrene workshop, and 1 heat exchanger in a styrene workshop were all cleaned using high-pressure water jet technology, covering a total cleaning area of 7,772 m². Cleaning pressure: 65~70 Mpa, cleaning time: 150 hours. Cleaning effect: The device shows a metallic shine.

High-pressure water jet cleaning machine technology utilizes the principle of liquid pressure enhancement; through a high-pressure pump, the mechanical energy from the power source (electric motor) is converted into pressure energy. The water with this high pressure energy then passes through a small-orifice nozzle (another type of transducer), where the pressure energy is converted back into kinetic energy, thereby creating a high-speed jet (WJ). High-pressure water jet cleaning requires precision equipment and accessories, including a three-plunger pump, an elastic transmission system, a high-pressure gun, foot valves, high-pressure hoses, powerful rotary nozzles, pipe nozzles, fan-shaped nozzles, flat cleaners, and three-dimensional rotary nozzles, among other accessories. At the same time, this technology also possesses the following features: First, it has a fast cleaning speed – due to the scouring, chipping, and grinding effects of the water jet (also known as water bomb abroad), the structure can be immediately broken apart and removed. Its cleaning speed is several times to dozens of times faster than that of traditional chemical methods, sandblasting and shot blasting methods, as well as simple mechanical and manual methods. Assuming that tap water is used as the medium for the jet, its high energy allows for thorough cleaning without the need for any additives or cleaners, resulting in very low costs. 　　Secondly, the cleaning cost is low: at the same time, the water consumption is very low, 2 cubic meters per hour. It is only about 1/3 of that required for chemical cleaning; in other words, high-pressure water jet cleaning uses fine jets, and thanks to its continuous operation, it consumes less water and energy, making it an energy-efficient device. 　　Finally, it offers high safety: the water jet cleaning method is safe and spark-free, allowing operations to be carried out even when tanks are filled with oil. This reduces the number of cleaning steps and saves costs. High-pressure water jet cleaning boasts unparalleled advantages in terms of cleaning efficiency, power consumption, cleaning costs, and environmental friendliness; its widespread adoption is an inevitable trend.

High-pressure water jet cleaning machine technology utilizes the principle of liquid pressure enhancement; through a high-pressure pump, the mechanical energy from the power source (electric motor) is converted into pressure energy. The water with this high pressure energy then passes through a small-orifice nozzle (another type of transducer), where the pressure energy is converted back into kinetic energy, thereby creating a high-speed jet (WJ). High-pressure water jet cleaning requires precision equipment and accessories, including a three-plunger pump, an elastic transmission system, a high-pressure gun, foot valves, high-pressure hoses, powerful rotary nozzles, pipe nozzles, fan-shaped nozzles, flat cleaners, and three-dimensional rotary nozzles, among other accessories.

The high-pressure water jet cleaning machine technology utilizes the principle of liquid pressurization; a high-pressure pump forces water to pass through small nozzles. Due to the scouring, cutting, and grinding effects of the water jet (also known as water cannon abroad), structures can be immediately broken apart and removed. Its cleaning speed is several times to dozens of times faster than that of traditional chemical methods, sandblasting and shot blasting methods, as well as simple mechanical and manual methods. Assuming that tap water is used as the medium in the jet, its high energy allows for thorough cleaning without the need for any additives or cleaners, resulting in very low costs ； High-pressure water jet cleaning boasts unparalleled advantages in terms of cleaning efficiency, power consumption, cleaning costs, and environmental friendliness; its widespread adoption is an inevitable trend. The kind commonly used in car washes is just that ； It’s just that the pressure on businesses is higher ； The equipment is more complex ；

The principle of high-pressure water jet cleaning is to use a high-pressure pump to generate high-pressure water, which then travels through pipes to the nozzle, where the high-pressure, low-flow water is converted into a low-pressure, high-flow jet； Then, the jet acts continuously on the surface to be cleaned with its high impact kinetic energy, thereby removing the scale and achieving the purpose of cleaning.

I understand the technology now. Are there any practical devices you can recommend?