What are the cleaning methods and techniques for mechanical parts?

Now if the mechanical equipment stops working, it needs to be cleaned. So for such small mechanical parts How should it be cleaned? The following is the cleaning method of mechanical parts that I have compiled for you. I hope it can help you.

How to clean mechanical parts

1. Manual removal method: Use metal brushes, scrapers and other tools to remove dirt on the surfaces of parts and components manually. This method also includes wiping the surfaces of parts and components with cotton, silk fabrics, synthetic fiber products, and suede to remove dirt.

2. Mechanical tool cleaning method uses electric or pneumatic tools to drive metal brushes, soft grinding wheels, etc. to remove carbon deposits, rust, paint, etc. on the surfaces of parts and components.

3. The compressed air blowing method uses compressed air to blow away dry dust, sludge, etc. covering the surface of parts and components.

4. High-pressure water washing method

5. Abrasive cleaning method uses soft abrasives and hard abrasives guided by compressed air flow or pressure water flow to hit the surface of the part to destroy the dirt layer and Take away with the residue. Mainly used to remove carbon deposits, rust and paint.

Principles of material selection for mechanical parts

Usage performance of materials

The main basis for material selection

Refers to how the parts are used when used The material properties that should be possessed include mechanical properties, physical properties and chemical properties. For most parts, mechanical properties are the main energy indicators. The parameters characterizing mechanical properties mainly include strength limit σb, elastic limit σe, yield strength σs or σ0.2, elongation δ, area shrinkage ψ, impact Toughness ak and hardness HRC or HBS, etc. Among these parameters, strength is the main performance indicator of mechanical properties. Only when the strength meets the requirements can the parts be guaranteed to work properly and be durable. In the study of materials mechanics, it has been discovered that the allowable stress used when designing and calculating the dangerous cross-sectional dimensions of parts or checking the safety level must be derived based on material strength data.

Processing properties of materials

The processing properties of materials mainly include: casting, pressure processing, cutting processing, heat treatment and welding. The quality of its processing technology directly affects the quality, production efficiency and cost of parts. Therefore, the process performance of materials is also one of the important basis for material selection.

Casting properties: Generally speaking, alloys with low melting point and small crystallization temperature range have good casting properties. For example: the crystalline component of the alloy has the best castability.

Pressure processing performance: refers to the ability of steel to withstand hot and cold deformation. Good cold deformation performance is marked by good formability, high processing surface quality, and less prone to cracks; while good hot deformation performance is marked by good ability to accept thermal deformation, high oxidation resistance, wide deformability temperature range, and hot brittleness tendency. Wait.

Cutting performance: Tool wear, power consumption and surface finish of parts are indicators of the cutting performance of metal materials, and are also one of the important basis for reasonable selection of materials.

Weldability: To measure the welding performance of a material, the strength of the weld zone is not lower than that of the base metal and does not produce cracks.

Heat treatment: refers to the behavior of steel during heat treatment.

Such as overheating tendency, hardenability, temper brittleness, oxidative decarburization tendency and deformation and cracking tendency to measure the performance of the heat treatment process.

In short, good processing technology can greatly reduce the power and material consumption of the processing process, shorten the processing cycle and reduce the scrap rate. Excellent processing performance is an important way to reduce product costs.

Economic performance of materials

The product cost of each machine is an important indicator of labor productivity. The cost of the product mainly includes: raw material cost, processing cost, finished product rate, production management cost, etc. The selection of materials should also focus on economic benefits, based on national resources and the actual domestic production. In addition, the service life and maintenance costs of parts should also be considered. If new materials are selected, research and test fees should also be considered.

Applications of mechanical parts

Metal materials

1. Cast iron

Mechanical parts

Both cast iron and steel They are iron-carbon alloys, and their difference mainly lies in the carbon content. Iron-carbon alloys containing less than 2% carbon are called steel, and those containing more than 2% carbon are called cast iron.

Cast iron has appropriate fusibility and good liquid fluidity, so it can be cast into parts with complex shapes. In addition, it has good shock absorption, wear resistance, cutting performance and low cost, so it is widely used in machinery manufacturing. Commonly used cast irons include: gray cast iron, ductile iron, malleable cast iron, alloy cast iron, etc. Among them, gray cast iron and ductile iron are brittle materials and cannot be rolled and forged. Among the above-mentioned cast irons, gray cast iron is the most widely used, followed by ductile iron.

2. Steel

Compared with cast iron, steel has high strength, toughness and plasticity, and its mechanical properties and processing properties can be improved by heat treatment. The blanks of steel parts can be obtained by forging, stamping, welding or casting, so they are widely used.

According to its use, steel can be divided into structural steel, tool steel and special steel. Structural steel is used to manufacture various mechanical parts and components of engineering structures; tool steel is mainly used to manufacture various cutting tools, molds and measuring tools; special steel is used to manufacture parts that work in special environments. According to chemical composition, steel can be divided into carbon steel and alloy steel. The properties of carbon steel mainly depend on the carbon content. The higher the carbon content, the higher the strength of the steel, but the lower the plasticity. In order to improve the properties of steel, steel with some alloying elements deliberately added is called alloy steel.

1) Carbon structural steel

The carbon content of this type of steel generally does not exceed 0.7%. Low carbon steel with a carbon content of less than 0.25% has low strength limit and yield limit, high plasticity, and good weldability. It is suitable for stamping and welding. It is often used to make screws, nuts, washers, shafts, Valve guides and welded components, etc. Low carbon steel with a carbon content of 0.1% to 0.2% is also used to make carburized parts, such as gears, piston pins, sprockets, etc. Carburizing and quenching can make the surface of the parts hard and wear-resistant, and the core tough and impact-resistant. If higher strength and impact resistance are required, low carbon gold-containing steel can be used. Medium carbon steel with a carbon content of 0.3% to 0.5% has good comprehensive mechanical properties. It has high strength, certain plasticity and toughness. It is often used as bolts, nuts, keys, Parts such as gears and shafts. High carbon steel with a carbon content of 0.55% to 0.7% has high strength and elasticity and is mostly used to make ordinary leaf springs, coil springs or wire ropes.

2) Alloy structural steel

The purpose of adding alloy elements to steel is to improve the properties of the steel. For example: nickel can increase the strength without reducing the toughness of steel; chromium can increase hardness, high temperature strength, corrosion resistance and improve the wear resistance of high carbon steel; manganese can improve the wear resistance, strength and toughness of steel; the role of aluminum Similar to manganese, its impact is greater; vanadium can improve toughness and strength; silicon can improve elastic limit and wear resistance, but will reduce toughness. The effect of alloying elements on steel is very complex, especially when several alloying elements need to be added at the same time in order to improve the properties of the steel. It should be noted that the excellent properties of alloy steel depend not only on the chemical composition, but also on appropriate heat treatment to a greater extent.

3) Cast steel

The liquid fluidity of cast steel is worse than that of cast iron, so when casting with ordinary sand molds, the wall thickness is usually not less than 10mm. The shrinkage rate of steel castings is greater than that of iron castings, so the rounded corners and transition parts of different wall thicknesses of steel castings should be larger than those of cast iron parts.

When selecting steel, you should try to use cheap and abundant carbon steel that meets the requirements of use. When alloy steel must be used, silicon, manganese, boron, and vanadium alloy steel should be given priority. .

3. Copper alloy

Copper alloys are divided into bronze and brass. Brass is an alloy of copper and zinc, and contains a small amount of manganese, aluminum, nickel, etc. It has good plasticity and fluidity, so it can be rolled and cast. Bronze can be divided into two types: tin-containing bronze and tin-free bronze. They have good friction reduction and corrosion resistance, and can also be rolled and cast. In addition, there are bearing alloys, which are mainly used to make bearing bushings for sliding bearings.

Non-metallic materials

1. Rubber

Rubber is elastic and can absorb more impact energy. It is often used as couplings or shock absorbers. Elastic elements, belt drive tapes, etc. Hard rubber can be used to make water-lubricated bearing liners.

2. Plastics

Plastics have a small specific gravity and are easy to make parts with complex shapes. Moreover, various plastics have different characteristics, such as corrosion resistance, heat insulation, and electrical insulation. , anti-friction, large friction coefficient, etc., so its application in machinery manufacturing has become increasingly widespread in recent years.

Plastics made of wood chips, asbestos fibers, etc. as fillers and pressed with thermosetting resin are called bonded plastics. They can be used to make parts such as instrument brackets and handles that are not subject to much stress. Plastics made from layered fillers such as cloth, asbestos, and thin wood boards as a matrix and pressed with thermosetting resin are called laminated plastics. They can be used to make silent gears, bearings, friction plates, etc.

When designing mechanical parts, selecting appropriate materials is a complex technical and economic issue. Designers should make comprehensive considerations based on the use of the part, working conditions and physical, chemical, mechanical and process properties of the material, as well as economic factors. This requires designers to have extensive knowledge and practical experience in materials and processes. The foregoing are only some rough explanations. The chemical composition and mechanical properties of materials can be found in relevant national standards, industry standards and mechanical design manuals.

What are the general cleaning methods for mechanical equipment?

Some large-scale equipment and machines now need to be cleaned regularly when working in the open air. So do you know what to do with mechanical equipment? How to clean and maintain it? The following is the general cleaning method of mechanical equipment that I have compiled for you. I hope it can help you.

General cleaning methods for mechanical equipment

1. Dry cleaning: use a sponge or other absorbent material, spray some cleaning agent or something on it, and wipe it after completion. Use a relatively wet object to wipe it again, and finally use a dry object to dry all the areas you just cleaned

2. Rinse directly with water until it is clear, and then wipe it dry with a dry object; This device is not afraid of water.

How to clean mechanical parts

Scrubbing. Put the parts into a container with diesel, kerosene or other cleaning fluid, and scrub with cotton gauze or brush. This method is easy to operate and has simple equipment, but has low efficiency and is suitable for single pieces and small batches of small parts. Under normal circumstances, it is not advisable to use gasoline because it is fat-soluble and can damage human health and easily cause fires.

Cook and wash. Put the prepared solution and the parts to be cleaned into a cleaning pool of appropriate size welded with steel plates, heat it to 80~90℃ with a stove under the pool, and boil and wash it for 3~5 minutes.

Spray cleaning. The cleaning fluid with a certain pressure and temperature is sprayed onto the surface of the parts to remove oil stains. This method has good cleaning effect and high production efficiency, but the equipment is complex and is suitable for cleaning parts with less complex shapes and serious grease on the surface.

Vibration cleaning. The parts to be cleaned are placed on the cleaning basket or cleaning rack of the vibration cleaning machine and immersed in the cleaning liquid. The vibration generated by the cleaning machine simulates the manual rinsing action and the chemical action of the cleaning liquid to remove oil stains.

Ultrasonic cleaning. The chemical action of the cleaning fluid and the ultrasonic oscillation introduced into the cleaning fluid work together to remove oil stains.

Cleaning and care solutions for mechanical parts

Organic solvents. Common ones include kerosene, light diesel oil, gasoline, acetone, alcohol and trichlorethylene. Using this dissolving method to remove oil can dissolve various greases. The advantages are that it does not require heating, is easy to use, does not damage metal, and has good cleaning effect. The disadvantage is that most of them are flammable, high cost, suitable for precision parts and parts that are not suitable for cleaning with hot alkali solution, such as plastic, nylon, cowhide, felt parts, etc. However, please note that rubber parts cannot be cleaned with organic solvents.

Alkaline solution. Alkaline solution is an aqueous solution of alkali or alkaline salt. It uses an emulsifier to emulsify non-saponifiable oil to remove oil. It is the most widely used decontamination cleaning fluid.

Emulsification is the formation of extremely small particles from one liquid that are evenly distributed in another liquid. Adding an emulsifier to the alkali solution to form an emulsion can reduce the surface tension and adhesion of the oil film, so that after the oil film is broken into extremely small oil droplets, it will no longer return to the metal surface to remove oil stains. Commonly used emulsifiers include soap, water glass, bone glue, gum, triethanolamine, synthetic detergents, etc. It should be noted that different cleaning fluids should be used to clean parts made of different materials. Alkaline solutions have varying degrees of corrosive effects on metals, especially aluminum. Table 1 and Table 2 respectively list the formulas of cleaning fluids for cleaning steel parts and aluminum alloy parts for reference.

When cleaning with alkaline solution, the solution generally needs to be heated to 80~90℃. After degreasing, rinse with hot water to remove residual alkali on the surface to prevent parts from being corroded.

In addition, there are some auxiliaries in the cleaning agent that can improve or increase the comprehensive performance of the metal cleaning agent such as anti-corrosion, anti-rust, and carbon deposit removal.

Four requirements for maintenance of mechanical equipment

Neediness: tools, workpieces, and accessories are placed neatly; safety protection devices are complete; lines and pipelines are complete.

Cleaning: The inside and outside of the equipment are clean; all sliding surfaces, screws, gears, racks, etc. are free of oil and bruises; all parts are free of oil, water, air, and electricity leaks; chips Trash is swept away.

Lubrication: Refuel and change oil on time, and the oil quality meets the requirements; the oil pot, oil gun, oil cup, linoleum, and oil lines are clean and complete, the oil mark is bright, and the oil line is smooth.

What are the cleaning methods for mechanical parts and equipment?

Oil stains on engineering machinery parts are mainly caused by unsaponifiable oil, dust, impurities, etc., so what should be done for these mechanical parts and equipment? How to clean it? The following is the cleaning of mechanical parts and equipment that I have organized for you. I hope it can help you.

Cleaning of mechanical parts and equipment

1. Three cleaning solutions

Organic solvents. Common ones include kerosene, light diesel, gasoline, acetone, alcohol and trichlorethylene. Using this dissolving method to remove oil can dissolve various greases. The advantages are that it does not require heating, is easy to use, does not damage metal, and has good cleaning effect. The disadvantage is that most of them are flammable, high cost, suitable for precision parts and parts that are not suitable for cleaning with hot alkali solution, such as plastic, nylon, cowhide, felt parts, etc. However, please note that rubber parts cannot be cleaned with organic solvents.

Chemical cleaning fluid. It is a chemically synthesized aqueous solution of water-based metal cleaning agent. The metal cleaning agent is mainly composed of surfactants and has strong decontamination ability. In addition, there are some auxiliaries in the cleaning agent that can improve or increase the comprehensive performance of the metal cleaning agent such as anti-corrosion, anti-rust, and carbon deposit removal.

The principle is that the cleaning fluid prepared from the cleaning agent first wets the surface of the part, and then penetrates into the contact interface between the dirt and the part, causing the dirt to fall off and disperse from the surface of the part, or dissolve in the cleaning fluid, or in the cleaning fluid. Emulsion and suspension are formed on the surface of the parts to achieve the purpose of cleaning the parts.

Common cleaning agents configured with chemical cleaning solutions include LCX-52 water-based metal cleaning agent, CW metal cleaning agent, JSH high-efficiency metal cleaning agent, D-3 metal cleaning agent, DJ-04 metal cleaning agent , NJ-841 cleaning agent, 817-C oil cleaning agent, CJC-8 liquid metal cleaning agent.

The preparation method, concentration, cleaning temperature and heating measures of the above-mentioned cleaning agents must strictly comply with the requirements of their instructions. The temperature should be strictly controlled during manual cleaning, and you can use a brush or cloth to clean. If there is serious oil stain or carbon deposit, you can use a wire brush to clean it. It should be soaked for a certain period of time before cleaning to meet the needs of moisture and soaking. Cleaning can be divided into rough cleaning and fine cleaning. If the oil stain in the cleaning fluid after cleaning is not serious, the upper layer of floating oil stain can be skimmed off and used again.

2. Five cleaning methods

Spray cleaning.

The cleaning fluid with a certain pressure and temperature is sprayed onto the surface of the parts to remove oil stains. This method has good cleaning effect and high production efficiency, but the equipment is complex and is suitable for cleaning parts with less complex shapes and serious grease on the surface.

Ultrasonic cleaning. The chemical action of the cleaning fluid and the ultrasonic oscillation introduced into the cleaning fluid work together to remove oil stains.

Note: The cleaning method should be reasonably selected according to the causes and characteristics of oil pollution to ensure the normal use of parts, avoid corrosion or damage to parts caused by cleaning, and prevent environmental pollution and subsequent contamination of parts.

Classification method of mechanical parts

Category 1 is mainly used for precision machinery and has high requirements on the stability of the fit. It requires the parts to be damaged during use or after being assembled several times. The wear limit of its parts does not exceed 10% of the dimensional tolerance value of the parts. This is mainly used on the surfaces of precision instruments, meters, precision measuring tools, and the friction surfaces of very important parts, such as the inner surface of the cylinder, the main journal of precision machine tools, and coordinates. The main journal of the boring machine, etc.

Category 2 is mainly used for ordinary precision machinery, which has higher requirements for the stability of the fit. It requires that the wear limit of the parts does not exceed 25% of the dimensional tolerance of the parts, and requires a good close fit. Contact surfaces are mainly used in machine tools, tools, mating surfaces with rolling bearings, tapered pin holes, and contact surfaces with high relative motion speeds such as mating surfaces of sliding bearings, gear tooth working surfaces, etc.

What are the commonly used cleaning agents in mechanical cleaning

Mechanical equipment is generally widely used in engineering factory projects, so if you find that one day the mechanical equipment becomes dirty , so what kind of cleaning agent should be used to clean machinery? The following are the cleaning agents commonly used in mechanical cleaning that I have compiled for you. I hope it can help you.

Commonly used cleaning agents in mechanical cleaning

1. Petroleum-based solvent cleaning agents

Types of petroleum-based solvent cleaning agents. Petroleum is a mixture of various hydrocarbons. The various hydrocarbons contained in petroleum are usually fractionated from petroleum at different temperatures according to different uses. Petroleum fractions, which are generally used as detergents and solvents, have a strong ability to remove oily dirt present in machinery. There are four types of this type of cleaning agent according to the fractionation range:

1. The fraction when the fractionation range is 40~60℃, 60~80℃, and 80~120℃ is petroleum ether for washing.

2. Fractions with a fractionation range of 80 to 120°C are mostly used as solvents in the rubber industry. Fractions with a temperature range of 145 to 200°C are mostly used as solvents in the paint industry.

3. When the fractionation range is between 40 and 180°C, the fraction is light gasoline for washing, which is suitable for washing precision machinery.

4. When the fractionation range is 150-300℃, the distillation part is kerosene, of which 195-260℃ is solvent kerosene. The high boiling point part above 295℃ in the kerosene part is re-fractionated into diesel for washing.

Characteristics of petroleum solvent cleaning agents. Petroleum-based cleaning agents have many characteristics, and these characteristics must be fully considered when using them to achieve better cleaning results. From the perspective of cleaning technology, its characteristics include: dissolving power; volatility; flash point; autoignition point; explosive concentration, etc.

1.Solubility. The ability of a solvent to disperse and dissolve solutes is called solvency, which is often used as the main indicator for evaluating solvent-based cleaning solutions. The stronger the dissolving power, the faster the solvent can clean dirt and the higher the cleaning quality.

2. Volatility. Refers to the evaporation rate of a solvent at a specific temperature. The surface being cleaned dries quickly if the evaporation rate is fast, so cleaning agents with different volatilities can be selected according to specific conditions and requirements. Generally, the main factor that determines the evaporation rate is the latent heat of evaporation of the solvent itself. However, the specific heat, thermal conductivity, surface tension, polarity and molecular weight of the solvent and the vapor density of the liquid surface during evaporation also have an impact on the evaporation rate. The speed of volatility also determines the concentration of the solvent vapor in the surrounding environment. There is a certain limit to the concentration of solvent vapor allowed in the air. Taking into account the flash point of the solvent, when the solvent vapor concentration reaches this limit, it will cause an explosion or combustion in the event of an open flame, which is absolutely not allowed.

3. Flash point.

Solvent cleaning agents are all flammable substances, and fires must be strictly prevented during production and use. Therefore, in addition to volatility, flash point must also be considered. When the solvent is heated, vapor is emitted into the air. When the temperature rises and the vapor concentration reaches a certain value, a flame will occur when encountering an open flame. This temperature is called the flash point. The flash points of commonly used gasoline are very low, almost all below room temperature, so be sure to guard against open flames when using them to avoid fires.

2. Organic solvent cleaning agents

Organic solvent cleaning agents generally have special cleaning purposes in mechanical cleaning, such as cleaning oil-free parts and conductive parts in machinery. Commonly used organic solvent cleaning agents include alcohols, ethers, ketones, benzene, etc.

Ethanol is a colorless and transparent liquid with a specific gravity of 0.794, a boiling point of 78.3°C, and a flash point of 14°C. Ethanol can dissolve natural resins and many synthetic resins, and is completely miscible with water, hydrocarbons and castor oil. It is an important organic solvent. The interaction between ethanol and acetic acid can produce ethyl acetate under the catalysis of strong inorganic acid, which is also an important organic solvent. Ethanol can be used as a raw material to prepare paint strippers for certain paint layers. Anhydrous ethanol is often used as a dehydrating agent in demanding cleaning processes. This is because the presence of hydroxyl groups in the ethanol molecules enables hydrogen bonds to be formed between the molecules and water molecules to carry water.

Ethyl ether is a colorless liquid, slightly soluble in water, with a boiling point of 34.5°C and a specific gravity of 0.73. The main use of ether is as a solvent. It can dissolve many organic compounds and is suitable for cleaning certain organic precision parts. Ether is volatile, easy to catch fire, and easy to explode. Keep away from fire sources when using it.

Acetone is a colorless liquid with a boiling point of 56.1°C. It is flammable and volatile. It is miscible with water, ethanol, ether, chloroform, etc. It has strong solubility in resins and greases and is an excellent paint remover. One of the main components.

Benzene and its homologues are colorless liquids, insoluble in water, and soluble in organic solvents such as gasoline, ether, acetone, and carbon tetrachloride. It has a strong ability to dissolve oily dirt and has a certain effect on removing carbon deposits on piston engines. It is also a good solvent for coal tar bitumen and natural bitumen. This type of solvent is flammable, volatile and highly toxic. Pay attention to safety during use and avoid inhaling its gas.

3. Non-flammable chlorinated hydrocarbon cleaning agents

The properties of non-flammable chlorinated hydrocarbon cleaning agents. Chlorinated hydrocarbon cleaning agents are part of organic solvents. Because they are non-flammable and non-explosive, and have special cleaning processes, they are classified into another category. The physical properties of commonly used chlorinated hydrocarbon solvent cleaning agents are shown in Table 2-3.

Chlorinated hydrocarbon solvents have strong solubility in grease, low boiling point, small specific heat, and small latent heat of evaporation, so they heat quickly and condense quickly. Compared with air, the specific gravity is larger than that of air. Stay in the lower part. The most widely used solvent of this type is trichlorethylene.

Trichlorethylene has strong degreasing power and is an excellent cleaning agent for grease. It is also very volatile. Taking the evaporation rate of ether as the unit, if ether is 1, then trichlorethylene is 3.8. Therefore, there is no need to dry when using trichlorethylene solvent for cleaning. Trichlorethylene is suitable for cleaning ferrous metals and oil-free products. If a stabilizer is added, it can also be used for cleaning aluminum alloys and titanium alloys. In addition, trichlorethylene has many properties, which should be paid attention to during use, otherwise it will cause adverse consequences. Precautions for using trichlorethylene are as follows:

1. Trichlorethylene is poisonous. When using it, you should be careful that the trichlorethylene vapor in the air does not exceed the poisoning limit, so the workplace should have good ventilation facilities;

2. Trichlorethylene is prone to explosion when heated with strong alkali. Therefore, it is strictly forbidden to come into contact with strong alkali during use. It is particularly noteworthy that when removing the acid in the cleaning tank, it is not allowed to Use caustic soda;

3. When trichlorethylene is exposed to light, air, and moisture, it will decompose to produce hydrogen chloride acidic gas, causing metal corrosion, so care should be taken to separate it from water and be careful when cleaning. There is special equipment that can not only separate water, but also recover solvents so that solvents can be recycled;

4. Trichlorethylene is easily decomposed and produces harmful hydrogen chloride. In order to prevent trichlorethylene from For decomposition, stabilizers must be added. Commonly added stabilizers include diethylamine, triethylamine, pyridine, tetrahydrofuran, etc., and the dosage is 0.1 to 0.2%.

The traditional Chinese medicine red peony root is also a good stabilizer for trichlorethylene, and its dosage is 3 to 4%. Another function of adding these stabilizers is to neutralize the hydrochloric acid in the cleaning solution;

5. Trichlorethylene vapor in the air will produce acid gas when it comes into contact with open flames or hot plates, such as welding arcs and open heaters. Therefore, when using trichlorethylene to remove oil, it cannot be in the same room as the above-mentioned related equipment. used simultaneously.

Types of cleaning using chlorinated hydrocarbon cleaning agents.

The decontamination effect of chlorinated hydrocarbon cleaning agents is the same as that of all solvents, which is the dissolution of dirt. Its ability to dissolve dirt is related to the type and molecular structure of the dirt.

The specific heat of chlorinated hydrocarbon cleaning agents is small, and the latent heat of evaporation is also small, so it heats up quickly and condenses quickly. Therefore, cleaning with it mainly relies on the gas it evaporates. When encountering cold cleaning When parts are removed, it immediately condenses and turns into liquid, dissolving the oil and falling to the bottom of the cleaning tank. Then new gas comes into contact with the cleaning parts, condenses into liquid, and so on. In this way, the surface of the workpiece with oil stains adhered to it is always in contact with the clean cleaning fluid. And because the cleaning agent vapor can reach any part of the parts to be washed, the cleaning effect is good. According to the cleaning characteristics of chlorinated hydrocarbons, commonly used cleaning types can be summarized into five forms.

1. Steam type. The use of steam to remove oil stains uses solvents with relatively low boiling points, which are generally used to clean oily dirt with low adhesion. Since the solvent vapor can reach any part of the cleaning parts, the cleaning efficiency is high and the speed is fast. Suitable for cleaning heavy and thick parts.

2. Liquid gas type. The items to be washed are immersed in the heated solvent liquid, and the grease and dirt are dissolved in the solvent by the penetration and mechanical action of the hot solvent, and then the solvent vapor is used for further cleaning. This cleaning process is suitable for cleaning parts with complex shapes and can remove dust, iron filings, oil stains, etc. on the surface of the parts.

3. Air spray type. While steam degreasing, solvent is added for powerful spray cleaning. It is suitable for cleaning parts with complex shapes. It has a better cleaning effect on grease-type dirt with strong adhesion, and can simplify and reduce the cleaning equipment. It has the widest adaptability and can meet the cleaning requirements of general metal parts.

4. Liquid jet type. In order to improve the cleaning quality, a combination of the above methods is used. First, soak in hot solvent, and then use steam and powerful spray cleaning at the same time. This method is suitable for large quantities of parts with complex shapes.

5. Two-phase cleaning. Two-phase cleaning is carried out by utilizing the characteristics of certain chlorinated hydrocarbon cleaning agents that have a specific gravity greater than water and are insoluble in water. Chlorinated hydrocarbons are one phase in the lower layer, and water is the other phase in the upper layer. The parts enter the solvent through the water layer. This is suitable for cleaning small batches of parts and parts that are not suitable for heating. Can be used to remove oil-soluble and water-soluble dirt and remove paint from parts.

Since most of these cleaning agents are toxic and can be recycled, special cleaning equipment must be used when using them. The equipment itself can recover the cleaning fluid for recycling, and it is best to be in a sealed form. Depending on the characteristics of the cleaning parts, the cleaning equipment can be one-tank or multi-tank.

How to clean mechanical parts

1. Manual cleaning method: Use metal brushes, scrapers and other tools to remove dirt on the surfaces of parts and components manually. This method also includes wiping the surfaces of parts and components with cotton, silk fabrics, synthetic fiber products, and suede to remove dirt.

3. The compressed air blowing method uses compressed air to blow away dry dust, sludge, etc. covering the surface of parts and components.

4. High-pressure water flushing method