chengcg – Page 194 – CNC Machining & Turning, Milling, Metal parts

The importance of selecting metal cleaning agent in hardware workpiece cleaning process

Metal workpiece welding process, before welding cleaning treatment is very important, for different metal workpiece material, the welding process requirements are different, the need to choose different metal workpiece cleaning agent, the general market hardware material is divided into steel, carbon steel, alloy steel, cast iron and so on. According to different shape and Application different, its cleaning The process method is also different, but the cleaning agent for hardware work can be the same. Below, Dongguan Mingkang industry and according to the response of many years customer, summed up the common process and method of cleaning hardware workpiece.

Cleaning process before welding

1. Cleaning process before steel welding

1. The most widely used cleaning treatment for soft steel before welding is sandblasting, and the best welding intensity is sand blasting.

2. Before stainless steel is cleaned before welding, stainless steel is the only steel in all steel materials that has higher welding strength after acid etching. The commonly used etching methods are dichromic acid oxidation treatment, water vapor jet cleaning aggravated chromic acid treatment, nitric acid mixed acid oxidation, nitric acid hydrofluoric acid mixed solution after oxidation treatment of dichromic acid passivation treatment.

Two. Cleaning process before painting

Iron and steel should be treated with degreasing and rust removal before spraying, and phosphate treatment should be carried out to form a phosphate protection film on the surface of the washed steel to prevent rust.

The typical process of cleaning steel before painting is impregnation. It includes the following processes:

Degreasing, washing, rust removing, water washing, surface dressing, phosphating, film forming, washing, post-treatment and drying.

Three. Cleaning of oil pressure pipeline

When installing the oil pressure device, the pipeline must be adequately pickled. Before the liquid bath is pickled, remove the dirt from the pipes with significant corrosion or bonding with the wire brush. The application of paint film on the inner wall of the pipe is stripped and pickled. Degreasing and cleaning should be carried out for pipes with antirust oil or grease. Acid washing was carried out by acid washing, water washing, neutralization and washing. Acid pickling is usually carried out at room temperature with a 5% hydrochloric acid solution containing a corrosion inhibitor. The pipe can be cleaned after cleaning the pickling tank, and can also be cleaned by acid circulation after assembling the pipeline. It is more efficient to use the pump to circulate the acid in the pipeline after the pipe is assembled. The process is to clean 3H with 5% hydrochloric acid at normal temperature, rinse the acid with water, and then neutralize 2H with 0.5% sodium hydroxide or sodium carbonate solution, and then wash the water fully.

Four. Degreasing, rust removing and rust prevention “three in one” cleaning.

In common use of carbon steel pipes, reaction towers, storage tanks, heat exchangers, heating furnaces, sealed tanks and other equipment, or complete sets of industrial equipment, chemical cleaning treatment, such as oil removal, descaling, rust removal and passivation, should be carried out before and during the operation to improve the purity of the product to avoid catalytic agent poisoning and to improve heat exchange efficiency of heat exchange equipment. Reduce energy consumption and cooling water consumption. At present, the typical cleaning processes used in complete sets or equipment are: degreasing cleaning, discharge (waste liquid treatment), water rinsing, acid washing, discharge (waste liquid treatment), water rinsing, rinsing (citric acid treatment), neutralization (ammonia treatment), antirust treatment (passivation), discharge (waste liquid treatment) and end.

Traditional basic substances (three sodium phosphate, sodium hydroxide, sodium carbonate, etc.) are used to remove oil and degrease, and then carry out acid cleaning and rust removal (hydrochloric acid, nitric acid, sulfuric acid, hydrofluoric acid, citric acid, etc.), and then passivate under alkaline conditions. An oil removal, rust removal and antirust “three in one” cleaning agent with phosphoric acid as the main agent can be used in the new equipment (such as pipes and tanks) to finish the process of removing oil, rust and rust. Compared with the traditional cleaning process, the cleaning process can be greatly shortened and the discharge amount of 4/5 washing wastewater can be reduced.

The main ingredients of the “three in one” cleaning agent are phosphoric acid, phosphoric acid, two hydrogen zinc, tartaric acid or citric acid, surfactant, film accelerating agent, etc. The inhibitor used in conjunction with the “three in one” detergent is alkaline, so it should be added temporarily.

1, “three in one” cleaning and rust prevention principle

The main function of cleaning and rust removing in the “three in one” cleaning agent is the phosphoric acid.

(2) the protective effect of film forming under acidic condition is that phosphates, such as two hydrogen and zinc phosphate, can form protective films. The “three in one” antirust effect is mainly reflected in the formation of a dense phosphating film on the metal surface after cleaning and rust removal.

In order to accelerate the formation of the passivation film, the film promoter is added. The role of the film promoter is to make use of its synergistic effect to increase the micro cathode area, accelerate the rapid oxidation of hydrogen evolution and promote the formation of the membrane.

Iron ion masking agents such as tartaric acid or citric acid, such as tartaric acid or citric acid, can play a complex role in the iron ions in the solution. The iron ions, which are rapidly elevated in the solution, are controlled in a certain concentration, avoiding the excessive iron ion concentration, which can catalyze the corrosion of the metal and promote the rust removal and film formation. The synergy of each other.

The effect of surfactants is to reduce the cleaning step and make the “three in one” cleaning also have the function of removing oil at the same time. The addition of surfactants can not only improve the emulsification, wetting, infiltration, dispersion and solubilization of a small amount of oil, but also improve the uniformity and corrosion resistance of the film, and improve the surface cleanness. Therefore, it is possible to avoid the occurrence of dust or whitening on the metal surface after cleaning. Surfactant is the preferred nonionic surfactant.

The study showed that the formula was 25% to 30% phosphoric acid

Application of ceramic sand on wear-resistant castings

Characteristics of spherical ceramic sand for casting
[Characteristics]
1, because of the solid appearance of the gravel and the small surface area, the amount of 1/3 binder (resin, R2O nSiO2 and so on) can be reduced. Good fluidity, making sand mold, core easy to fill the dense no dead angle, in the casting process, low gas and good air permeability, can reduce defects to improve the rate of finished products and reduce the cost of raw materials.
2. High refractoriness, low thermal expansion coefficient and good high temperature stability. During the casting process, no sand sticking, no sintering and easy collapsing can greatly reduce the deformation of castings, reduce cleaning work and reduce labor intensity.
3, the particle size distribution is reasonable, and the strength of mold and core is improved.
4, the bulk density of JNY-XT (casting spherical ceramic sand) is 1.79-1.87g/cm less than the accumulation density of chromium iron ore (2.5~2.7g/cm), and the weight of the sand core is easily carried and the use of core sand is reduced.
5. The non natural mineral sand belongs to the high temperature smelting artificial sand making, the chemical index is stable, the physical property is unified, the PH is neutral, and it can be constructed with all kinds of acid and alkaline binder.
6. High temperature is not cracked, the hardness of the spherical gravel is high, and the recycling rate is high.
Application scope of JNY-TCS (spherical ceramic sand for casting)
1, widely used in resin sand, sodium silicate sand, clay sand casting process sand core and type sand.
2. The substitute chromite ore is widely used in sand core sand for sand core of engine water jacket core, oil channel core and tappet core.
3. Replace the chromite ore as the surface sand and the secondary sand (back sand) for the steel castings.
4, commonly used as sand mold dry sand used in EPC process and V process.
5. As the main raw materials for advanced refractory products (ladle draining sand, self flow castable, casting coating etc.).
6. It is widely used as cleaning sand for casting copper and aluminum alloy castings.
Application of spherical ceramic sand for casting in the production of wear resistant castings
The spherical ceramic sand used for casting is a synthetic spherical refractory particle of aluminum silicon system formed by the high temperature melting of the EAF and the high temperature smelting by electric arc furnace. TCS has an artificial property with uniform chemical composition and stable physical properties. It is different from the existing spherical sand (pearl sand, electric melting ceramsite, etc.) in the market.
1, linear expansion rate
The expansion of TCS is linear expansion without phase transformation and sintering.
2, grain shape
3. Refractoriness
According to the index listed in Table 1, TCS is in accordance with the data shown in the two element phase diagram of Al Si refractory material, and the refractoriness is >1850 C through the inspection by the third party inspection mechanism.
4. Advantage of using sodium silicate as binder to produce high manganese steel.
(1) promoting grain refinement
Principle: it is well known that, in order to improve the wear resistance of high manganese steel castings, its grain must be refined, the primary condition for grain refinement is to make it fast and uniformly cool, then how to let the high temperature cast metal liquid can lose the heat evenly and quickly is the weight of the weight.
1 thermal conductivity
TCS is a high density solid spherical sand produced by manual smelting. The thermal conductivity is greater than that of silica sand, which is slightly smaller than that of chromite ore. It is between 0.3-0.5W/ (MK).
2 permeability
In the casting model, heat loss is carried out by air flow at high temperatures. Under the accumulation state, the TCS is uniform and orderly with the capillary network structure which can directly connect the air. Under the physical action of the hot air, the heat is evenly and quickly carried away through the capillary network to complete the rapid and uniform cooling. The thermal conductivity is smaller than that of chromite. Beyond the defects of chromite sand, though the thermal conductivity is strong, the accumulated heat can not be taken away quickly.
The above two points indicate that TCS has excellent heat dissipation ability and can promote crystal refinement.
(2) melt recycled materials for neutral materials
The melting material of neutral material contains the following meaning: resist the erosion of grit by manganese alloy under high temperature, remove impurity after high temperature, and have uniform physical and chemical properties.
3, reduce the amount of binder added
Through the application test, the water glass carbon dioxide hardening process is used in the TCS modeling, and the same construction strength is achieved. The addition of water glass is 2-3%, which is less than the 6-7% of silicon sand.
The decrease of the amount of water glass can reduce the content of water in the molding sand in order to reduce the gas defects, improve the collapsibility of the sand, reduce the labor intensity and production cost, and reduce the discharge of the waste.
4. High recovery and reuse performance
TCS gravel has high surface density, high temperature, no cracking, no breakage, little grain shape change and low regeneration cost.

Ripple shape and characteristics of corrugated compensator

First.
The compensator is also called expansion joint. In the piping system, the bellows compensator can absorb the thermal expansion caused by temperature difference while bearing the pressure of the system. The compensator is composed of corrugated elements and nozzle, cylinder, outer guard tube and end plate. Successful applications have been obtained in metallurgical, petroleum, chemical, electric, heating and refrigeration systems, as well as low temperature equipment, which can be absorbed to the axial, transverse and angular displacement. The typical working conditions are: pressure from vacuum to 6.4MPa, and temperature from -200 to 1350 C.
Unlike ordinary pipe elements, the bellows are made of quite thin materials to make it flexible enough to absorb the mechanical displacement and thermal displacement expected in use, and also play a role in vibration and noise reduction. In the design, manufacture, transportation, installation, testing and other links, we must pay attention to the uniqueness of this product.
Custom made stainless steel corrugated expansion compensator, high temperature corrugated compensator

Two. Bellows design and main performance parameters
Bellows are the core components of bellows compensator, and are the key functional components of bellows. The performance of bellows compensator mainly depends on bellows element.
Classification of wave structure of 2.1 bellows
Corrugated tubes are divided into U shape, Omega shape, S shape and C shape. The different waveforms have different performance characteristics.
Characteristics of 2.1.1 U shaped bellows

U bellows is the most widely used waveform at present. Its characteristics are: under the same wall thickness condition, the bearing capacity is high, the compensation ability is large, the stress distribution is uniform, the fatigue life is high, and the comprehensive performance is good. The performance of U bellows is mainly determined by wall thickness, wave height, wave spacing, layer number and so on.
Characteristics of 2.1.2 Omega bellows

The shape of the Omega bellows is characterized by high resistance to the section, but low compensation capability and low rigidity. The utility model is suitable for occasions with high pressure, small displacement and small deflection, and the manufacturing process is complex.
Characteristics of 2.1.3 C shaped bellows

The C shape bellows are characterized by high bearing capacity, low compensation capability, high rigidity and simple manufacturing process. In general, it is not used.
Characteristics of 2.1.4 S shaped bellows

S shaped bellows are characterized by high pressure bearing capacity, but the compensation ability is slightly lower, the process is poor, and the manufacturing is more complex, but it is not easy to produce stress concentration, the stress state of the bellows is better, and the stiffness is lower than the U shape. S type bellows can be used when both high pressure and large displacement are required.
At present, bellows compensators are mostly using U bellows. The U shaped bellows has good manufacturability, easy processing, good pressure resistance and compensation capability. No enhancement U bellows are generally suitable for occasions with pressure less than 2.5MPa.
2.2 U shaped bellows are classified according to the number of layers
It can be divided into single layer bellows and multi-layer bellows.
Single layer bellows consist of a tube wall, easy to fabricate, but the compensation capability is general. The multilayer bellows is made up of multi-layer tube walls, which are like many thin leaf springs, so the stiffness is small. Compared with single-layer bellows, the multilayer bellows are easy to deform and have great compensation capability under the same wall thickness and wave shape. The stress generated by the deformation is small and the fatigue life is high. Therefore, it can meet the requirements of large compensation and high pressure impact (single layer bellows require tube wall thin, ripple depth, multi-layer bellows requiring pipe wall thickness, ripple shallow) under certain working conditions, that is, under certain pressure, compensation and fatigue life, multi layer bellows are smaller and shorter than single layer bellows. The multi-layer corrugated expansion joint is compact in structure, saving material and easy to manufacture. Because of the small wave height, it is easy to install the outer sleeve and easy to install and support. When corrugated expansion joints are used for corrosive environments, multilayer bellows are made of corrosion resistant materials both inside and outside, thus saving valuable metals. Sometimes, for the sake of antisepsis, the inner and outer layers can be made of materials with larger thickness. In addition, if the inner layer of the inner wall appears to be cracked for one reason, such as corrosion, defect, fatigue, installation and so on, although the inner layer has leaked, the other layers can still be sealed, so the multi-layer corrugated expansion joints are not easy to burst and prolong the maintenance period.

Nylon wheels improve productivity on grinding and polishing

We are experiencing an era of rapid technological development. Up to now, the hardware and electronic machine industry “by machine generation” trend, nylon wheel has its wear resistance, corrosion resistance, anti aging, light weight, non-toxic and other advantages to replace the ideal material for non-ferrous metals. There are two kinds of stainless steel columns, one is polishing and the other is drawing. As the name suggests, polishing stainless steel can be used as a kind of human like effect.

Nylon wheel is often used in the sand belt after sand strip light treatment and mirror front treatment, it causes high cost of polishing artificial high price naturally will also become higher. As for drawing out, the first skin of stainless steel, and then the workpiece over nylon wheel, can be finished, many people have good effect, the foreign customers who have all the love and export happy In the light of the effect of throwing, the domestic customers prefer the feeling of wire drawing and frosting. Nylon wheels are also important abrasives for surface treatment.
Undefined

The nylon wheel can be conveniently installed on the existing electric or pneumatic tools, and different workpiece components can be selected according to the needs: the utility model can be used for the surface treatment and processing of various equipment, containers, hardware machines, and wood tools, which saves the previous manual work and can effectively reduce the labor intensity. High work efficiency, at the same time reduce the consumption of raw materials per unit area. There are many types of nylon wheels, generally divided into: 3P, 5P, 7P, 9P, 12P, 15P, etc. the product sand numbers are generally divided into: 90#, 120#, 150#, 180#, 240#, and so on.

Black screws are more likely to rust? Teach you to prevent black screws from rusting!

Many sourcing found that the blackening screws are very easy to rust. Many enterprises have repeatedly received complaints, accusing enterprises of selling inferior products. So is this true? Whether the blackening screws are easier to rust is explained by the surface technology of screws.
Blackening is a chemical surface treatment process, the principle is to produce a layer of oxide film on the surface of the metal, thereby isolating the air, to achieve anti rust effect. In the comparison of several common surface processes, such as galvanizing, cadmium electroplating and dacroa, it can be seen that although the cost of blackening is cheaper and beautiful, its anti rust performance is poor and easy to rust.
Undefined
The process determines the prerequisite for poor performance of blackening and rust prevention. But there are ways to protect blackening screws from rust.
First of all, after producing blackening screws, one step is to lubricate screws. Some customers will need to wipe off the oil during the purchase, which makes the screw lose the protection. It is easy to rust in wet environment such as rainy days during the transportation process.
Secondly, the rusting of screws has a lot to do with the storage environment. The warehouse should avoid wet environment, and the packing must be sealed. Or, when you store it, spray a layer of rust preventive oil.

The screws with rubber pads are big enough. Do you know the function of plastic flat pads?

There are thousands of screws, such a kind of screws, always with a pad, rubber pad and so on. Why is it easy to see the use of plastic mats on electronic and digital products? The purpose is to prevent electric conduction, light weight and so on. But in the mechanical industry, plastic fasteners, such as those mentioned above, are also widely used.
Ingenuity, fastener, sunk head, self drilling pin, drilling screw, machine and so on are all popular with many customers. The screws with rubber pads are not only scratched, but also electrically conductive. There are many important roles. Such as:
Undefined
1, sealing action, waterproof, leak proof. In practical applications, prevent water, oil and other liquids from slipping along threads.
2, prevent scratch 0, prevent scratches, such as the surface of the device, heat treatment paint layer.
3, anti loosening action. The cushion can also increase the stress area and play a role of tightening up and strengthening.

Practicality of surface treatment polishing

With the progress of the society, the requirements for the polishing of parts are becoming more and more strict, not only need to be practical, but also look good in appearance. This requires the appearance of polishing. Our company is a factory specializing in the production of polishing materials. We are adhering to the concept of quality priority, expanding step by step in the industry. The introduction of advanced machinery and equipment and first-class production line, if you want to buy Han Tong abrasive products, we are right to choose.

When polishing materials are polished, there are many kinds of polishing methods. Most people think that stainless steel is not rusty. In fact, it is not like this. Like many other metals, it will be oxidized and rusty when the hand contact or contact air is affected by the environment. In addition, the surface of stainless steel workpiece is machined, for example, welding. After the processing of joint, stamping, curling and heat treatment, a layer of black oxidation and metamorphic hardened layer has been formed, and many tiny burrs and sharp corners which are invisible to the naked eye and sharp angle are formed. In general, it is difficult to remove them by mechanical method and affect the performance of the properties of the material. In order to solve these problems, people use various methods to polish and Polish Stainless steel and other metal surfaces.
Undefined

In the process of the surface treatment of the workpiece with polishing material, the requirement of high polishing process is used. Because of the advantages of high strength, strong corrosion resistance and good heat resistance, stainless steel is widely used in industry, and the petrochemical industry, electronic machinery, medical equipment, light industrial products and personal residential decoration are used. Stainless steel products are all used in advanced hotel facilities. However, in the process of production, stainless steel is produced by casting, die forging, heat treatment and other processes. A layer of black oxide skin is formed on the surface, or the micro unevenness is left in the process of machining. In order to obtain the smoothness, brightness and service life of the stainless steel surface, it is necessary to carry out proper mechanical polishing of stainless steel, then chemical polishing or electrochemical polishing, in order to improve the value of the stainless steel and make it practical.

Making method and classification of nylon wheel

Nylon wheel is a kind of cutting wheel made with special synthetic non woven fabric and selected abrasive sand. It has a strong cutting force, the surface effect of its processing is consistent and the soft fiber can be suitable for various shapes, and it has many characteristics, such as self sharpness, non blockage of slit, durability and so on. But there are many cutting wheels on the market, so how do we identify nylon wheels?

Nylon wheels are mainly divided into two categories: wheel and wheel.

First, the superposition wheel is coated by the industrial white cleaning cloth through the roll glue, and one piece of stack pressure is combined in the oven to bake and solidify, and then flush and cut. The coiling wheel is coated by the same method and is rolled into a stick on a special tube core and baked and solidified.
Nei

Two, nylon wheel products are supported by the three-dimensional network of nylon Web. The grinding workpiece has the characteristics of elastic grinding, cold cutting, anti blocking and so on. It is more delicate, softer and brighter than the grain of the same grain number grinding wheel. Compared with cloth wheel and hemp wheel, the cutting force is stronger and the lines are clearer.

The maintenance and cleaning method of the cupboard hardware hand

The cabinet is in the kitchen humid, smoked fire and fire environment, this environment is easy to cause the cupboard hardware accessories and cupboard hardware pull hands rusty, corrosion, so in the maintenance of the cabinet, can not forget the cabinet hardware pull maintenance work, then how does the cupboard hardware handle carry on? Below the small editor for everybody detailed explanation The maintenance of the cupboard hand.

The maintenance and cleaning methods of the cupboard hardware hand are:

1, the cabinet hardware handle with water stains should be dried in time to avoid the rusting of the cabinet hardware.

2, the hinge and drawer slide of cabinet should be oiled regularly to keep the opening and pulling smoothly.

3, cabinets pull on the best is not hang things; do not look at the cupboard little hand, it is playing a very important role, it is an important part of the cabinet, it directly determines the establishment of a good cabinet, cupboard not only to cooperate with the style of the cabinet as a whole, more needs to meet the personal habits of the chef, a Beautiful and functional cupboard handles can make your cooking at one go. From the outside look, the hand has a bar, a ball, a tube shape and a variety of geometric shapes. The hardware hand is designed or visible or concealed. The consumers can choose according to their personal habits.

4, when the cabinet door is not regular or loose, it can adjust the hinge. Now the hinge used in the market can be adjusted in three dimensions.

How about fasteners? What is the use of the fastener?

With the growing social and economic growth, people’s living standards are also rising, the quality of life is getting better and better, when buying anything, more will be placed on the quality of the product. Especially for fasteners, they pay more attention to the quality of products. So there are more and more products we buy, so you may have a problem, that is to accumulate a lot of fasteners, such as a variety of manufacturing materials, they may come from machinery, construction and other fields, and many of the sources of fastener acquiring company in the market come from this. Many of these things may not be reconciled when garbage is thrown away, but what can they do?
Undefined
First, if we are happy to use these materials for other uses, we will be able to do so. A flat bar is a good material. In fact, the source of this material is mainly made up of carbon steel, which can be used as a good link material in other places, which is a fun and saving resource, and we can find a lot of flat – key gadgets on the Internet.
Second, if our family machinery has problems, they are good alternatives. We can do some simple repairs ourselves. When our home machinery problems need to be replaced, we can replace them directly to avoid the trouble of finding someone to repair it.