Application of the hottest heat treatment energy s

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Application of heat treatment energy saving in production process

Abstract: This paper describes the application of heat treatment energy saving in actual production, analyzes and discusses the ways and methods of heat treatment energy saving in technology and management. Make the heat treatment technology achieve the goals of energy saving, emission reduction, high quality and high efficiency

key words: heat treatment, energy saving, process flow, system, management, production

our company is a manufacturer of construction machinery. Many parts and components in the machinery industry need heat treatment to achieve the designed mechanical conditions, give full play to the performance of materials, ensure product quality, and improve the level of mechanical components and their competitiveness in the market. Our company formally established the heat treatment division at the end of 2005. At the initial stage of planning, we optimized the layout of heat treatment equipment, process flow, power supply equipment and quenching cooling system based on the principle of energy conservation and emission reduction, and stipulated them in the form of documents

the energy-saving aspects of heat treatment described here are mainly composed of several factors:

1): whether the heat treatment process is effective to make the treated workpiece meet the technical requirements of its design at a lower cost

2): whether the heat treatment equipment has been effectively and reasonably used in operation, such as continuous production, and the time for the equipment to wait for the workpiece has been reduced. And there is no additional heat loss

3): whether the heat treatment operators, process technicians, and production management personnel have good communication, and everyone can be effectively managed and organized production

1. Heat treatment process:

in the traditional process calculation time: t=k*a*d, t is the heating time, K is the furnace charging coefficient, a is the heating coefficient, and D is the effective thickness of the workpiece. In fact, in actual production, we usually calculate the holding time based on previous work experience and the effective thickness of the workpiece. In large quantities, we use actual experience or observe the fire color of the workpiece, which is mainly reflected in carbon steel and low alloy steel, This is because carbon steel has no alloying elements and carbides, so it does not need long-term heat preservation and uniform austenitizing process. Because the heat transfer coefficient of low alloy steel is basically similar to that of carbon steel, the heat transmission time of the workpiece is mainly determined by its effective size. For a single workpiece in production, when the furnace temperature has reached the process design, what operating principle does the experimental machine follow? Next, as our technicians look at the fixed value, that is to say, when the surface of the workpiece has reached the process temperature value, the workpiece has been fully burned. Do not add additional holding time. This is what we often call "zero" holding heating. For mass production, we usually heat the furnace first, and then put the workpiece into it after reaching the temperature. When the furnace temperature reaches the process time again, we add a certain homogenization time, which can relatively shorten the process cycle, save energy and reduce costs

alloy structural steels (40Cr, 35CrMo, 42CrMo), etc. because some alloy elements are added to their materials, it takes a certain time for us to homogenize the carbides in the heating process, so it takes a little more time than carbon steel. Generally, we also need about 60% - 80% of the traditional process time. This can shorten the heating time of steel parts at high temperature, reduce the deformation relatively, and the austenite grain is relatively small, After quenching, fine martensite structure can be obtained, and its mechanical properties will be improved to a certain extent, which is also the effect that our heat treatment workers want to achieve

2. Parts charging

1): in actual production, when the number of workpieces is limited, it is not cost-effective to arrange the furnace number separately. In this case, we can mix different workpieces and materials into one furnace under the condition of roughly the same process parameters, such as Cr12MoV and 8407 or H13, 40Cr and 42CrMo. The quenching temperature is roughly the same, so the charging capacity can be met. Similarly, when the tempering temperature is the same, different parts and materials can be mixed in one furnace, and the tempering time can be implemented according to the longest tempering time

2): in fact, many products of our company are not nearly the same, and the quantity is not much, but in order to reduce the deformation, sometimes we increase the heat treatment tooling, so I don't use heat-resistant stainless steel many times, and most of them are replaced by ordinary low-carbon steel, mainly because the material price is low, and the quantity is not much

3. Heat treatment cooling medium

because many mechanical parts of our company are alloy structural steel, when considering quenching medium. I choose aqueous solution. Aqueous solution quenching avoids the situation that the hardness value of oil quenching for heat treatment of large-diameter medium carbon low alloy steel may not reach, and water quenching is easy to crack. Water soluble synthetic quenching liquid is especially suitable for low and medium carbon steel induction and large quenching, and water-soluble synthetic quenching liquid is especially suitable for low and medium carbon steel induction and large quenching. Different cooling rates can be obtained by adjusting the concentration, The quenched workpiece is bright and has short-term rust prevention effect. It can be tempered directly without cleaning, and there is no oil smoke. No oil smoke, no combustion, no fire hazard, improve the working environment. It is not easy to age and deteriorate and has a long service life, compared with oil products. 4. The cost of 30 minutes after the specimen is formed is relatively small

4. Tempering process: the tempering process is determined by the tempering temperature of the parts. The word "rock" is the general term of the furnace waste heat of rock mass. The general rule is that the tempering temperature of the parts is about 300 degrees lower than the furnace waste heat temperature. In this way, the furnace will soon reach the set value of the tempering process temperature after the workpiece is put into the furnace, and multiple tempering is better than one tempering, Therefore, cobalt accounts for 60% in the pool of waste hand motors produced in large quantities. The microstructure and properties obtained by the second tempering are better than those obtained by the first tempering, and the cost is correspondingly reduced

5. Equipment maintenance: we should regularly repair the equipment during production and check the tightness of furnace and furnace door. The instruments and meters related to the distribution box shall be calibrated and maintained regularly to reduce the loss caused by boiler shutdown due to electrical failure. The maintenance of relevant operating equipment such as trolley and traveling crane can reduce the loss caused by inconvenient access to the furnace

6. Control of heat treatment quality: in fact, the workpiece itself is saving energy during heat treatment. If a workpiece has not undergone effective and reasonable heat treatment, the service life of the part will not be very long. If the component fails in the early stage, it is necessary to make new components to replace, which must consume raw materials, machining hours, and other related costs. Effective and reasonable heat treatment can double the service life of the workpiece. Therefore, good heat treatment quality can avoid early failure of the workpiece, and can avoid a series of procedures such as heat treatment repair (normalizing, re quenching and tempering, correction, stress relief and tempering) of the workpiece. Therefore, there was a slogan in our country in the 1970s: "do a good job in heat treatment, one top several parts"

energy saving in heat treatment is often related to process management. Reasonably arrange work, reduce furnace shutdown time, and put the furnace heating time stage at the time stage when electricity is cheap. Most of the time, the implementation of the process in place is related to management. The company should strictly formulate process procedures, equipment operation standards, and relevant technical standards. In terms of production arrangement, it is necessary to produce in batches and at full load as far as possible. If the furnace loading is not enough, the furnace shall be combined, and preparations for various heat treatment work shall be made in advance. Regularly check the operation of heat treatment equipment


actively improve the professional level, operation level and related work awareness of heat treatment personnel, and improve the work attitude of heat treatment personnel. Because most of the time, the final decisive factor is "people". When the relevant hardware cannot be changed, the working attitude of personnel is software. We can formulate relevant systems, implement reward and punishment regulations, count and assess energy consumption in production, and carry out rectification and management for defects

energy conservation and emission reduction play a very important role in our work. How to save energy, improve production efficiency, reduce costs, and establish our own brand in the market competition. The improvement of production and technology management is an important measure to implement the development of science and technology and the development of enterprises. Energy saving consciousness starts from me, from now on, and from every bit of work. Make the heat treatment technology achieve the goals of energy saving, emission reduction, high quality and high efficiency. It also makes the product quality and cost control at a certain level in the market. (end)

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