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Factors Affecting Dimensional Precision of Precision Casting

In general, the precision precision of cast parts is affected by the casting structure, casting material, mold making, shelling, roasting, pouring and other factors, any one of the links set, the operation will cause the casting shrinkage will change, Resulting in casting dimensional accuracy and requirements are biased. The following are the factors that can cause defects in the accuracy of Precision casting:
(1) the impact of casting structure: a. Casting wall thickness, shrinkage, casting wall thin, small shrinkage. B. Free shrinkage rate, hinder the shrinkage rate is small.
(2) the impact of casting material: a. The higher the carbon content of the material, the smaller the line shrinkage, the lower the carbon content, the greater the line shrinkage. B. Common material casting shrinkage rate is as follows: casting shrinkage K = (LM-LJ) / LJ × 100%, LM for the cavity size, LJ for the casting size. K is affected by the following factors: wax mold K1, casting structure K2, alloy type K3, casting temperature K4.
(3) the impact of molding on the shrinkage of the casting line: a. Wax temperature, wax pressure, holding time on the size of the melt to the temperature of the most obvious wax, followed by wax pressure, holding time in the guarantee The effect of melt-molding on the final size of the melt is very small. B. The line shrinkage of the wax (mold) material is about 0.9-1.1%. C. When the mold is stored, shrinkage will be further generated, the shrinkage value is about 10% of the total shrinkage, but after 12 hours of storage, the die size is basically stable. D. The radial shrinkage of wax mold is only 30-40% of the shrinkage rate in the longitudinal direction. The effect of wax wax temperature on the free shrinkage is much greater than that on the shrinkage shrinkage (the best wax temperature is 57-59 ℃, The higher the temperature the greater the contraction).
(4) the impact of shell material: the use of zircon sand, zircon powder, on the shop sand, shop powder, because of its small expansion coefficient, only 4.6 × 10-6 / ℃, so negligible.
(5) the effect of shell roasting: the expansion coefficient of the shell is small, when the shell temperature is 1150 ℃, only 0.053%, so it can be ignored.
(6) the impact of casting temperature: the higher the pouring temperature, the greater the shrinkage, pouring temperature is low, the smaller the shrinkage, so the pouring temperature should be appropriate.

asked 15 hours ago in Physics by anonymous
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Raymond grinding equipment quality is more important than the price

Raymond mill equipment quality is more important than the price, equipment quality and price I am afraid that customers have been most concerned about the issue, but some people think about such a problem? What is the quality and price in the end? Here are the general Xiaobian to explain their views and opinions.
Milling equipment is important to the quality or price? Inexpensive is the highest standard for the pursuit of each consumer, but this standard seems difficult to achieve, for some customers concerned about the price, do not care about the quality of equipment, can pay attention to use, and some people pay more attention to quality, do not care The price of the level, no matter which of the above is not entirely correct, there is a certain degree of deviation and extreme, quality and price are relatively speaking, between the two to achieve a balance is the best result, so GM Xiaobian That the price and quality are very important, will be about the level of words, Xiao Bian that quality is more important than the price point.
Why is the quality of Raymond milling equipment more important than the price? Give you a little story: for example, you buy a mobile phone, there are two different price of the phone to choose from, a low price less, can only meet the most basic needs, a slightly more expensive, but the performance , The quality of the equipment is much higher than the former; if the purchase of a temporary save some of the funds, the former may face mobile phone failure, renewal and some other issues, and choose the latter to pay the corresponding cash, enough to use a year or two Replacement. This situation we have deep experience in life, many people choose different, the results of natural returns are different. So from the purchase of mobile phones can be seen that the quality of some more important than the price.

asked 15 hours ago in Computer Science by anonymous
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Research on the crushing rate of grinding mill

The crushing rate of grinding mill is not only related to the ore milling equipment, but to the property of the ores. When enlarged the crushing rate, the existing research mainly takes into consideration the average grinding diameter and the distribution of the grinding diameter, the diameter inside the grinding machine, adding grinding ratio, filling voidage and the rotary rate of the grinding machine. However, the main purpose of the consideration lies in the enlarging design of the machine, but the problem is that the scholars are unable to know the grinding proportion situation inside the equipment, nor the above-mentioned factors could reflect the influences of the material flow and the amount of the water added.

For this reason, the experts of powder grinding equipment of our company identify the function of the crushing rate in the practical production data. They established a model with the granularity distribution, operational conditions and the chemical composition of the rocks, and they think that the original model using several parameters to reflect all the changes in the grinding process is not appropriate and the crushing rate cannot be measured directly. As a result, they established a relationship model of the crushing rate function and the production condition in order to realize the soft measurement of the crushing rate function and strengthening the practical applicability of the model.

There is one sample and relating analysis discrepancy in the ore grinding and classification process data which brings difficulty to the production decision making and the process optimization and control. And what is more, since there is no granularity balance relationship in the ore grinding process itself, the coordination process of the granularity can only be excluded, for this reason, experts of our company also researched the data coordination question of the grinding and classification process after introducing the grinding process model on the basis of the overall balance of the model granularity.

asked 2 days ago in Computer Science by anonymous
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Precision casting industry development

Precision casting industry development goals are the following aspects:
First, the completion of the growth mode by the labor, resource-intensive to the technology capital-intensive changes from extensive pollution to green intensive type of change, the product quality, variety, the number of the world's advanced level, the proportion of high-quality materials Increase, the entire precision casting plant production efficiency, economic benefits doubled; environmental pollution has been effectively managed, initially built with the environment co-ordination of China's casting materials industry system.
Second, the formation of a number of reasonable structure, the overall level of high combination of research and development and education and training base, can continue to transport professional personnel, and constantly develop high-quality, high-grade casting new varieties of materials to meet the growing casting materials Need, and gradually increase the intensity of technology exports.
Third, to complete the industrial structure adjustment, out of a number of low technological level, poor product quality, serious pollution, poor economic efficiency of small precision casting plant, the formation of a relatively concentrated "small giant" and "Star Enterprise" to achieve "professional Of large-scale "production. In particular, to the emergence of one or two world-renowned enterprises to compete with the backbone of enterprises, their high level of technology, well-equipped, well-funded, advanced management level, can continue to provide high-end market, high-quality casting materials, market share High rate.

asked 2 days ago in Physics by anonymous
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How long is the run-in period of the Raymond Mill

What is the mill run-in period? How long does it take for a raymond mill? And milling customers understand that these are very important to the future production and operation, a lot of mill manufacturers will give customers to remind, and some will provide technical personnel on-site guidance and installation instructions to follow the completion of running, but inevitably some small manufacturers services imperfect , The machine is not responsible for any problems after the appearance of everything on the idea, then if it is still a beginning into the milling industry customers will suffer.
Why should Raymond milling equipment go through a certain period of time?
Simply say that some of the dry mill is also difficult to understand, here we have to give an example to understand, car owners know that the same car is the same factory, but after a different trip for some time There will be obvious differences, some based on new, all aspects of performance are not much change, and some will appear noise, steering wheel is not flexible and so on, why the same car after the same time there will be such a big difference? In fact, this is the car run-in period is not running in place of the reasons, so the novice no matter how good the car does not necessarily achieve the desired effect, for Raymond Mill is also the case, put into the production line must run on the mill in order to Early detection of problem handling, maintenance period to provide a strong guarantee of production.
How long is the run-in period, how to achieve the best run-in effect? Mill running time does not want to run a long time, usually in the test machine production of 60 hours or so, that is, 2-3 days time, this time grinding customers must not rush into the normal production, need to wait, run After the completion of the equipment to maintain a normal and stable operation of the position, we recommend that everyone run-in time than the daily grinding production more steward, the best skilled or professional technical field guidance to complete, try to avoid novice to run or otherwise likely to bring irreparable loss.

asked 3 days ago in Chemistry by anonymous
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Is there a good way to clean up the rubbish in the sand

Sand machine in the work after a period of time will always leave some garbage in the stomach, the accumulation of garbage will make the sand making machine itself, the weight, friction increases, so sand machine at work will spend more energy to deal with These have no effect on the job. Long-term clean-up will lead to equipment damage, so in order to protect the safety of spare parts, increase the efficiency of equipment, often clean the sand inside the garbage. The work of cleaning up the garbage is usually done at the end of the day's work, so that it will not affect the progress of work, but also in a day sand machine do not work time to carry out.
Cleaning equipment for the general use of pickling and alkaline washing method. The so-called pickling is the concentration of 20 percent of the hydrochloric acid solution and sand making machine and equipment where dirt, wait about 10 minutes after you can then rinse with water. This method is a certain risk, after all, the use of hydrochloric acid, hydrochloric acid is to adjust the concentration of the concentration of hydrochloric acid in the adjustment of the concentration of hydrochloric acid solution into the water, the constant stirring. In the course of the configuration is strictly prohibited into the water into the hydrochloric acid solution inside, because it brings a lot of risks, meaning that hydrochloric acid may be splashed up, hurt the staff, the concentration of the adjustment is also unfavorable, because hydrochloric acid is used once Out, there is no room to adjust again.

asked 3 days ago in Computer Science by anonymous
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Application and Development Prospect of Recycled Sand for Construction Waste

SBM machinery tells the application of construction waste and the development prospects of sand, because China is currently in the development of high-speed, high-speed company's construction, building renovation, infrastructure expansion, and all use of this product of sand and gravel. So in recent years, China's natural gravel material more and more can not meet the needs of China's construction. So a lot of sandstone material, where to find to meet our needs? Construction Waste Crusher industry gave people hope to give the enterprise power
In recent years, the norms of construction sand, so that China's sandstone industry began to have an optimistic outlook, since the development of natural sand to the current mechanism of sand (construction waste regeneration sand), including innovation in the sand, no one Does not contain a good prospect for the future of gravel material. Today and we simply understand the next on the application and development of gravel material.
Throughout the previous market, the production of natural sand is mostly extensive, not only broken the natural ecological environment, but also caused a waste of natural resources, and seriously affect the quality of construction problems. The same is due to the problem of natural sand, so that its related products are not effective use and development. This phenomenon has led to a lot of waste of resources and energy irrigated area, to the environment has also brought serious problems. The mobile crushing station has been perfectly used in Construction Waste Crusher projects
Now, the emergence of construction waste recycling sand can be considered a complete solution to this problem. By its extension of another product - sand aggregate, made of concrete blocks in the construction project is to be an effective promotion and use. The emergence of vertical impact crusher to the development of China's gravel material to enhance a level, and reduce the production of cement consumption. And all this credit is due to the construction waste regeneration sand.
Construction waste Recycled sand is made from construction waste as raw material, through a series of broken, absorption, sand and other links, and ultimately produce the sand we need material. Construction waste recycling sand to improve the quality of construction sand and application level, and to ensure the quality of the project. I believe that in the future time, construction waste recycling sand will be more effective to promote the role.

asked 4 days ago in Computer Science by anonymous
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stone production in various fields

With the development of economy, the progress of science and technology, endless new things. Innovation of science and technology but also promote the progress of the society and the times. The introduction of new technology and new things, but also for the development of brick crushing machine, in this case, a single stage gold ore crusher manufacturer to keep pace with the times and synchronized with the domestic and foreign advanced technology, the R amp; D investment money and energy, steadfast unremitting research a single-stage single segment hammer type higher quality the crushing machine, has become the latest help motive force to promote the new development of infrastructure construction. 

Single stage gold ore crusher manufacturer single-stage gold ore crusher more intelligent automation, has the ability of automatic detection and automatic alarm mechanism, so monotonous maintenance burden of people is greatly reduced; the single stage gold ore crusher manufacturer single-stage single stage gold ore crusher manufacturing processed stone grain shape is a cube, very good meet the infrastructure construction of stone strictly demand; single stage gold ore crusher manufacturer single-stage gold ore crusher is reinforced by the concept of environmental protection, increase the variety of environmental protection equipment, very conducive to environmental protection.

asked 4 days ago in Math by kmei4545 (180 points)
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Precision casting development prospects

Investment Casting is a fusible material made of fusible material, on which a number of layers of special refractory coating, after drying and hardening to form a whole shell, and then steam or hot water from the shell Melt the model, and then put the shell in the sand box, filled with dry sand in its surrounding shape, and finally the mold into the roasting furnace after high temperature roasting, casting or shell by roasting, pour molten metal in which Get cast.
The precision welding of the products obtained by Precision casting is very close to the final shape of the parts, which can be used without processing or very little processing. It is an advanced process of near net forming. It is an excellent process technology in the casting industry. Application is very extensive. It is not only suitable for all types of casting of various alloys, but also to produce the casting size accuracy, surface quality than other casting methods to be high, and even other casting methods difficult to cast the complex, high temperature, easy to process castings, Can be used to melt casting precision casting.
At present, the world's investment casting process has developed rapidly and widely used. From the current situation, the future development trend of the process is that the casting products are getting closer to the parts and components. The traditional casting is only blank, Market quick response. The complexity of parts and components and the quality of the increasingly high grade, research and development means more and more strong, professional collaboration began to show, CAD, CAM, CAE application of parts and components to become the main technology.
From the current development situation analysis, investment casting technology is very wide range of applications, the future development prospects to be broad.

asked 5 days ago in Physics by anonymous
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Production and price details of 50 tons of granite sand production line

Production of 50 tons of granite sand production line configuration list
Under normal circumstances, a complete granite sand production line will contain granite Sand Making Machine, in addition, will also choose some auxiliary equipment, such as jaw crusher, impact crusher and feeder, conveyor, etc., for The efficient operation of auxiliary sand making line. But to meet the different needs of customers processing, can be equipped with cone crusher, dust removal equipment. In addition, it can also be based on different process requirements, various models of sand making equipment under the combination, in order to meet the different requirements of customers.
Granite Sand Making Line Sand Making Process
Sand production line on the material processing, divided into jaw crusher crushing, impact crusher or cone crusher in the crushing, Sand Making Machine sand shaping three stages. Specific production process: the material from the vibrating feeder evenly sent to the jaw crusher for rough broken, rough after the material from the tape conveyor into the impact crusher or cone crusher for the two crushed, crushed material Is transported to the sanding machine for sand shaping, and then round sieve shade to achieve the finished product size requirements of the material was sent to the sand washing machine cleaning, cleaning the finished product after the conveyor belt is finished.

asked 5 days ago in Computer Science by anonymous
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Daily Production of Ore Milling Equipment

Power plant mill 'test does not change the tile' refers to the thermal power plant pulverizer of the gold pad in more than 60 ℃ high temperature work to maintain a stable state, not because of the bearing temperature and the export of lubricating oil temperature caused by rapid high temperature Bearing seat vibration intensified and then melted, there is a thermal ore milling equipment operation in the 'tile' phenomenon. 

Only the ore milling equipment 'trial operation does not change the tile', in order to allow the entire fire power plant safe operation In addition, the ore milling equipment in the work process, the fine grinding of coal powder is also related to the power of the power plant The In the thermal ore milling equipment to complete the grinding and grinding work, will be through the heat of the coal into the boiler, and then the coal combustion in the boiler after the formation of hot flue gas will flow along the boiler to exotherm, follow-up coal ash Separation. 

Power plant mill grinding efficiency and fine degree of a good guarantee, then easier, the coal in the boiler full combustion, but also can improve the utilization of coal and reduce the possibility of environmental pollution.

asked 5 days ago in Physics by kmei4545 (180 points)
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Construction waste disposal equipment for construction waste special crusher

At the beginning of the new year, the local two sessions were held this month. To the construction waste disposal industry is excited that in this year's local two sessions, on the promotion of construction waste disposal recommendations and comments have mushroomed. So what are the concerns and suggestions for building waste disposal?
In recent years, with the rapid progress of urbanization in Fuqing City, Fujian Province, road construction, area transformation involving more than one million square meters of housing relocation, resulting in a large number of construction waste. At present, these construction waste is basically landfill treatment, can not be recycled, resulting in waste of resources, destruction of the ecological environment.
Assembly construction can shorten the construction period, reduce construction waste, reduce environmental pollution. According to the General Office of the State Council in September 2016 "on the development of assembly-oriented construction of the guidance", the proposed timely introduction of Fenghua policy, in the "three five" period, vigorously support the development of assembly-style construction, promote Fuqing ecological civilization construction, Strengthen the construction waste management capacity. At the same time, in Fuqing City to carry out the Construction Waste Crusher pilot, the use of commercial operations, the implementation of classified classification of construction waste, such as grinding into powder, turning waste into treasure and so on.
Today, Xiamen City, Fujian Province has started construction waste resource utilization, as soon as possible into the ranks of resources to help the city building waste turning waste into treasure. Xiamen Honglu Sheng construction waste recycling projects are used from the SBM independent research and development of construction waste construction waste single-stage broken modular production line, the host using DPF construction waste special crusher, the performance is very stable, superb assembly skills, and very focused on environmental protection , The production of recycled aggregate processed into a block, paving brick, tile tiles and other building materials products, to achieve the construction waste recycling, reduction, harmless economic, social and ecological benefits.
In addition, SBM construction waste crusher is a domestic steel cutting device with a special garbage crusher, the host will not be blocked, recycled bone grain size is good, variable three broken broken single section, with the file model in the more cost-effective High, is the best building waste crushing equipment.

asked 6 days ago in Physics by anonymous
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Construction waste mobile crushing station

Construction waste mobile crushing station (also known as construction waste mobile crusher) Medium and thick machinery using advanced construction waste disposal technology, construction waste, industrial waste, cinder, coal rock, slag, fly ash, building materials, non-metallic solid waste , The solid waste application process, you can produce all kinds of quality testing in line with the norms of new building materials, according to the equipment configuration of the effective utilization of different construction waste can reach 80-100%, no secondary pollution, can be achieved almost Zero pollution, zero emissions of the ideal environmental effects. Construction Waste Crusher station is the construction waste from construction waste to renewable raw materials recycling economy, low carbon economy production and operation mode change. Turning waste into treasure, protecting the environment, is the current global development of building treatment of the preferred equipment.
Construction waste mobile crushing station structure:
Construction waste mobile crushing station by the mobile rack, feeder, construction waste dedicated crusher, sieve, belt conveyor, iron equipment, electronic control system and other components. Can also be configured according to customer requirements
Construction waste mobile crushing station works:
Raw materials from the loader directly to the silo, from the silo into the vibration feeder, by the feeder to the material evenly sent to the construction of garbage crusher; after the garbage crusher after the crushing of the material by the belt conveyor by the separator Sent to the vibrating screen; broken material by the vibrating screen sieve into three kinds of materials: 0-10mm material from the belt conveyor to the finished material yard. Wood and other debris transported by the belt conveyor to the waste field. Large material is returned to the garbage-specific crusher via the belt machine.

asked 6 days ago in Computer Science by anonymous
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Go To The Charity Mall
north carolina dmvPeople, especially females, stewardship respond towards conversations which have more psychological words included. Just take including, if perhaps you were to state that "Today's climate is bright", that which you had simply inferred on listener would be a fact. It's bright.
asked Aug 14 by CristineNnt5 (120 points)
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out of the mill's 'trial delivery

Double inlet and double is an important equipment in coal-fired units of thermal ore milling equipment. The safety and stability of operation are directly related to the whole work of the whole thermal power unit. Therefore, Must be carried out quality testing, which should be verified during the trial operation of the load, double into the double out of the coal mill function to achieve 'trial delivery of the tile' quality.

Double into the double out of the mill's 'trial delivery of the tile' refers to the thermal ore milling equipment of the Ukrainian bearing in more than 60 ℃ high temperature work to maintain a stable state, not because the bearing temperature and export lubricants temperature fast High temperature and lead to vibration at the bearing seat and then melt, then double into the double mill operation of the 'tile' phenomenon.

Only double into the double out of the coal mill 'trial delivery of the tile' in order to allow the entire thermal power unit safe operation In addition, low-speed coal mill in the course of work, the fine grinding of coal powder is also related to the ore milling equipment power combustion The quality of the. Generally after the low-speed coal mill to complete the pulverized coal mill, the use of hot air in the drum drying of coal, after the separation of the separator into the burner for combustion and heating. Because the structure of low-speed coal mill is very large, grinding the type of coal, so it is also widely used in thermal ore milling equipment power generation.

asked Aug 14 in Physics by kmei4545 (180 points)
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artificial sand making machine performance

Sand making machine is one of the most used equipment in the mining industry, is dedicated to the production of building sand, sand road equipment, can put all kinds of rock, gravel. Sand making machine made various size of buildings, made of sandy granularity, high compressive strength, than natural sand, manufactured by sand conforms to the architectural requirements, can improve the quality of construction, with the hot sand, sand making equipment is also increasingly popular.
The sand making machine is a for producing artificial sand with mechanical processing as the main way. With the popularization and application of artificial sand, it is also developing steadily. There are "rock stone" and "hot stone" two types of "rock stone" for abrasive material processing and strong; "hot stone" for abrasive material processing is not strong, "hot stone" into the sand rate 35% higher than "rock stone". The use of selective fragmentation and cleavage of advanced crushing principle, directly applied enough kinetic energy on the sand, and converting kinetic energy into the broken sand required by the impact, the material particles produced in many areas meet the material demand.
Sand production line we have been very familiar with, equipment is composed of vibrating feeder, jaw crusher, sand making machine, vibrating screen, sand washing machine, belt conveyor and other equipment combination, first by jaw crusher for coarse crushing, fine crushing of the crusher, the vibrating sieve get the required size, unqualified size by belt conveyor back river gravel sand machine sand process, according to the need can increase the sand washing machine, the impurities in stone wash. The sand making line can be produced by dry sand making and wet sand making process. The main difference is whether to use water or not. What kind of sand production line is adopted, and the users should combine their actual needs.

asked Aug 14 in Physics by anonymous
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What is the best production line for sand making machine?

Sand making machine production line is the main source of artificial sand, with the reduction of natural sand, artificial sand has become the current sand market subject, sand making machine has become the most popular products. So what kind of sand making production line configuration is the best, then we will introduce in detail.
Sand making production line production capacity
Sand production line is to consider the issue of the sand production line production capacity, we need to consider processing ability of each processing equipment, and on the basis of the main sand making equipment corresponding supporting equipment configuration, also needs to consider the raw materials and convenient finished feeding and discharge.
Sand making machine production line and environment
Special attention especially to the impact on environment, sand production line is no exception, in order to realize the production of green sand making machine line concept, in need when the configuration design of sand production line also takes into account the waste water, dust and other waste, is currently the focus of the planning and design of the production line of sand machine.
A good sand production line may need to invest more, but also represents the market competitiveness and better development potential, so we need a more comprehensive consideration, to achieve the production line more modern sand making machine.

asked Aug 14 in Computer Science by anonymous
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Construction waste crusher handling equipment is a new era of the combination

Construction waste crusher handling equipment:
This series of products are mainly low cost of operation, safe and reliable work, more uniform grain size, easy repair and other characteristics, it is more in refractory materials, ceramics, smelting, mining, building materials, glass and other industries, In the material crushing of the compressive strength of less than 250Mpa use.
Construction waste crusher working principle: Construction Waste Crusher equipment [E-type mobile crushing station]
The construction waste crusher is driven by the electric motor as the main driving force, and the eccentric shaft is driven by the sheave and the V-belt through the motor pulley, so that the material entering the crushing chamber is crushed and processed through the row The material is discharged from the finished product.
Construction waste crusher is divided into conveyor belt, crusher (rack part, reset the spring, flywheel, large pulley, fixed jaw and activities of the E plate, moving part, side guards, brackets and adjustment parts), dust removal system , Lubricating parts and so on.

asked Aug 12 in Computer Science by anonymous
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