In forging production, in addition to ensuring the required shape and size of the forging, it must also meet the performance requirements put forward during the use of the parts, which mainly include: strength index, plastic index, impact toughness, fatigue strength, fracture initial and Stress corrosion resistance, etc. For parts working at high temperature, there are also high temperature instantaneous tensile properties, durable properties, anti-deformation properties and thermal fatigue properties.

INFLUENCE OF FORGING ON METAL MICROSTRUCTURE AND PROPERTIES

The raw materials for forging are ingots, rolled products, extruded products and forging billets. Rolled material, extruded material and forging billet are semi-finished products formed by rolling, extruding and forging of ingots respectively. In forging production, using reasonable process and process parameters, the structure and properties of raw materials can be improved through the following aspects:

1. Break the columnar crystals, improve the macrosegregation, change the as-cast structure to the forged structure, and weld the internal pores under suitable temperature and stress conditions to improve the density of the material;

2. The ingot is forged to form a fibrous structure, and further through rolling, extrusion and die forging, the forgings can obtain a reasonable distribution of fiber directions;

3. Control the size and uniformity of grains;

4. Improve the distribution of the second phase (for example: alloy carbides in ledeburite steel);

5. To make the organization get deformation strengthening or deformation strengthening, etc.

Due to the improvement of the above structure, the plasticity, impact toughness, fatigue strength and durability of the forgings are also improved, and then the required hardness, strength and plasticity of the parts can be obtained through the final heat treatment of the parts. performance.

However, if the quality of the raw materials is poor or the forging process used is unreasonable, forging defects may occur, including surface defects, internal defects or unqualified performance.

INFLUENCE OF RAW MATERIALS ON THE QUALITY OF FORGINGS

The good quality of raw materials is a prerequisite to ensure the quality of forgings. If the raw materials are defective, it will affect the forming process of the forgings and the final quality of the forgings.

If the chemical elements of the raw materials exceed the specified range or the content of impurity elements is too high, it will have a greater impact on the forming and quality of the forgings. Appears hot and crisp. In order to obtain intrinsically fine-grained steel, the residual aluminum content in the steel needs to be controlled within a certain range, such as 0.02% to 0.04% (mass fraction) of A1 acid. If the content is too small, it will not be able to control the grain size, and it is easy to make the essential grain size of the forgings unqualified; if the aluminum content is too much, it is easy to form wood grain fractures under the condition of forming fibrous structure during pressure processing. Tear-shaped fractures, etc. For another example, in austenitic stainless steel, the more n, Si, Al, and Mo are contained, the more anionite phase, the easier it is to form band cracks during forging, and make the parts magnetic.

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Details can be accessed by clicking here:https://www.gold-emperor.com/influence-of-forging-process-on-forgings/

There are two types of crossed roller bearings, one is crossed cylindrical roller bearings, the other is crossed tapered roller bearings; crossed roller bearings have a long history of application outside, but only in recent years. Into the public’s vision, it is widely used due to its own uniqueness and incomparable advantages over other bearings. Many users will have some problems with the installation of crossed roller bearings, such as lubrication, installation, cleaning, etc. Today, I will explain to you, I hope it will be helpful to you.

Preparation before installation

1. Choose grease

Lubrication has an important influence on the operation and life of crossed roller bearings. Here is a brief introduction to the general principles of selecting grease. Grease is made of base oil, thickener and additives. Different types of greases with the same type and different grades have very different performances and different allowable rotation limits. Be careful when selecting them. The performance of lubricating grease is mainly determined by the base oil. Generally, the low viscosity base oil is suitable for low temperature and high speed, and the high viscosity base oil is suitable for high temperature and high load.

The thickener is also related to the lubricating performance, and the water resistance of the thickener determines the water resistance of the grease. In principle, different greases cannot be mixed, and even greases with the same thickener will have adverse effects on each other due to different additives.

2. Cleaning before bearing installation

The bearing surface is coated with anti-rust oil, you must carefully clean it with clean gasoline or kerosene, and then apply clean high-quality or high-speed high-temperature lubricating grease before installation and use. The impact of cleanliness on rolling bearing life and vibration noise is very large. But we don’t want to remind you that closed bearings do not need to be cleaned and refueled.

Bearing installation

1. Thoroughly clean the main shaft, bearing seat or other installation parts, remove oil or impurities, and confirm whether there are burrs or burrs.

2. Install the crossed roller bearing into the shaft or bearing seat: Because it is a thin-walled bearing, it is easy to tilt when it is installed. In order to prevent this phenomenon, please use a plastic hammer to strike evenly while keeping it level, and carefully install the crossed roller bearing into the bearing housing or on the shaft until it is confirmed by sound that the reference surface is not completely close. Do not directly hammer the crossed roller bearing surface and the non-stressed surface. Use pressure blocks, sleeves or other installation tools (tools) to make the bearing evenly stressed, and do not install it through the transmission force of rolling elements.

If the mounting surface is lubricated, the installation will be smoother. If the interference is large, the bearing should be heated to 80~90℃ in mineral oil and installed as soon as possible, and the oil temperature should be strictly controlled not to exceed 100℃ to prevent the reduction of hardness due to tempering and the influence of dimensional recovery. When it is difficult to disassemble, it is recommended that you use the disassembly tool to pull out and pour hot oil on the inner ring carefully. The heat will expand the inner ring of the rolling bearing, making it easier to fall off.

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Details can be accessed by clicking here:https://www.prsbearings.com/a/news/crossed-roller-bearing-installation-process.html

The compact rack is usually used to store the company’s documents, vouchers and archives. Because of its dense storage characteristics, it can improve the utilization of space and has been widely used. Before purchasing a compact racks, many units will first consider its load-bearing problem, what are the factors that affect the load-bearing of the compact racks, and the precautions when using it.

Factors affecting the load-bearing capacity of archives

1. Material quality affects load-bearing

Generally, the raw materials of the compact racks are cold-rolled steel plates, and other key parts are made of national standard steel plates. Therefore, when purchasing, you need to pay attention to whether the raw materials used by the manufacturer meet the standards, and whether the steel plates meet the standards. Only the compact racks that meet the standards and meet the standards can ensure the quality.

2. The structure of the house affects the load-bearing

In addition to the quality of the material that will affect the load-bearing of the compact rack, the floor where it is installed and the structure of the house will also affect the load-bearing. Different house structures and buildings, different floors, the load-bearing will also be different. Therefore, before purchasing, we also need to explain to the manufacturer the floor and house structure where our compact racks are to be stored, so as to facilitate the manufacturer’s evaluation.

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Details can be accessed by clicking here:https://www.etegreen.com/blog/factors-affecting-the-load-bearing-of-compact-racks/

An important application of calcium hydroxide is as a flocculant for water and sewage treatment. It forms fluffy charged solids that help remove smaller particles from the water, resulting in a more transparent product. This application benefits from the low cost and low toxicity of calcium hydroxide. It’s also used in freshwater treatment to raise the pH of the water so that the pipes don’t corrode when the base water is acidic because it’s self-regulating and doesn’t raise the pH too much.

Therefore, we should correctly select the production specifications of calcium hydroxide production line when purchasing equipment, otherwise it will affect the working efficiency of the equipment to a certain extent. So what are the production specifications of calcium hydroxide production line?

Due to the great demand for calcium hydroxide now, the use of basic calcium hydroxide equipment is also very large. With the use of the equipment, we will gradually diversify the specifications of the equipment according to the output of calcium hydroxide, so as to better Meet the needs of calcium hydroxide manufacturers and reduce some unnecessary investments in calcium hydroxide manufacturers.

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Details can be accessed by clicking here:https://www.ly-gaifeng.com/blog/specification-of-calcium-hydroxide-production-line.html

The briquetting machine has high operation efficiency, which can not only complete the production quickly, but also ensure the quality. In particular, the briquette briquette machine is related to the quality of the product, so it is necessary to eliminate unfavorable factors as much as possible for the working state of the briquette machine. In the long-term operation, the equipment of the briquetting machine will fail, and the briquetting machine may be blocked. What are the reasons for the blockage of the briquetting machine? Let’s take a look together~

Causes of blockage of the briquetting machine

1. The cutting speed is too fast, so that the production speed is lower than the feeding speed, and it is easy to cause blockage.

2. If the temperature of the material is too high, the humidity will be too high. Once the humidity is too high, the viscosity will inevitably increase, so it is easy to cause the briquetting machine to be blocked.

3. The material is doped with larger particles, therefore, the material cannot pass through the roller, resulting in blockage.
4. The speed of the briquetting machine is too slow, and it is difficult to demould the material. Usually, the speed of the briquetting machine should be maintained at about 10 to 20 rpm.

5. Special mold design will also lead to the difficulty of mold release. For example, rectangle and diamond shape are special. Usually, we need oval and round shape, which is convenient for mold release.

6. The management of materials is not in place, mainly because the coordination and communication of employees are not in place, resulting in uneven delivery of materials.

Common faults of briquetting machine equipment

1. No ball or no shape

In the use of briquetting machine equipment, sometimes the phenomenon of non-balling and non-forming occurs. The main reasons are insufficient feed, too low hydraulic pressure, soft roll skin quenching, and ball socket deformation. Insufficient feeding will make the briquetting machine without material to press, so add enough material to the briquetting machine; if the hydraulic pressure is too small, the material will not be fully pressurized. At this time, reduce the speed and increase the pressure. The deformation of the ball socket will make the shape of the material uneven, and it should be repaired or replaced in time.

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Details can be accessed by clicking here:https://www.zymining.com/blog/causes-of-blockage-in-the-briquetting-machine.html