2016年9月7日星期三

CHAENG slag grinding plant turnkey service

 1.Equipment Manufacture

Chaeng takes sole responsibility of all problems of grinding plant construction in EPC. Chaeng could select some main equipment basing on rich experience, so the
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 mine design is in step with equipment manufacture, which greatly shortens the construction period, and saves time and cost for customers. In order to strictly control the period, Chaeng will formulate detailed and feasible project schedule in EPC, and project control group strictly supervise the progress of project. 

2.Installation & Commissioning

1)Installation & commission technology

Installation & commission is key link of raw material test, mine design, and equipment manufacture, and directly takes influence on production.
Installation and commission of grinding plant equipment is a very careful work with strong practicality. Any error may lead to low capacity which cannot reach the expectation. For example: in different construction, the same type of equipment would have deviation because of the opening location and installation etc. These differences will have a significant impact on the final production efficiency.
In view of the importance of installation and commission, Chaeng established professional installation company having four installation teams which are from the mine 
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production line and led by engineering technicians who held the directors of grinding plant and mine leader. Installation personals Chaeng sent out participate in the whole mine design of clients, and there are two points for this: one is the old technicians are very familiar with structure, performance and using of Chaeng equipment; the other is the technician who can quickly solve many actual problems in plant construction understand the overall design of factory because of participating in the whole mine design.

2)Methods of Installation and Commission

For installation and commission, Chaeng upholds customer fist. There are 3 methods of installation and commission according to the actual situation of customers.
①Free guide of installation
Chaeng can send related technician to guide customer with the equipment installation and commissioning for saving customer's cost.The customer should responsible for the travel charge of the technician.
②Contract for materials
Chaeng arranges the installation and commission technicians, and clients prepare the components and instruments of installation of commission.
③Contract for labor and materials
Chaeng is responsible for tools, materials and personnel allocation of the installation and commission. Customers can directly wait for the final results.

3.Personnel Training

It is simultaneous for worker training and installation & commission in order to save time and cost. Worker training has two purposes, one is the grinding plant works earlier and produces benefit; the other is training technical team for customers to guarantee the normal operation of the factory in the future.
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The technicians who have extremely rich practical experience for worker training are experts of installation and commission team. They help workers to pay attention to some details which usually don't be easy to notice but extremely important. These Chaeng technicians provide training from 3 aspects:
1.Operation training for all workers involved in mine grinding processing
2.Training for the common problems in the plant operation and processing technology; a live solution demonstration for workers
3.Training of operation experience grasping, the workers should operate machines by lots of exercises.
Through the above three aspects of training, workers could skillfully operate mine grinding technology (grinding particle size, adding burdening etc.) and processing equipment. Customers have their own technical team, which can prevent the dressing plant from long time stop.
When the training is completed, Chaeng Company will present free “Common faults handling of mining equipment”, “The operating procedures of processing plant” and common forms, which is convenient to manage operation of grinding plant.

CHAENG cement plant turnkey service Pre-sales Service

 Engineering Consulting
I Purpose of Engineering Consulting
Engineering consulting makes clients have a comprehensive understanding of the value of mine, the useful elements, available mineral processing technology, plant size, required equipment and period. 
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II Contents of Engineering Consulting
Chaeng Technology Support Department is responsible for engineering consulting. When a client needs engineering consulting, firstly, Chaeng Research Institute will arrange an expert with rich dressing experienced to make sure the ore separability according to the analysis of mineral elements (Chaeng also makes this analysis). 
After making sure the ore separability, Technology Support Department would contact with mineral dressing construction departments including geology, mining, ore dressing, smelting, machinery, civil engineering, electric power to get a brief quotation.
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Chaeng mine consulting provides services according to the need of clients.  The main contents of mines consulting include mining, mineral processing, external conditions, investment estimation and analysis of economic benefit.
III Results of Engineering Consulting
At last, engineering consult takes on economic benefits analysis for the customers including the cost analysis and profit estimate.  Mine costs include mining, transportation, mining beneficiation, financial management cost. Profit estimate includes ore grade, product, price, annual output, total income, total cost, profit before tax, comprehensive estimation (time of recovering the investment).
Raw Material Testing
Mineral dressing test is in charge of Mineral Dressing Research Institute belonging to Chaeng Company
I Preparation before test
The clients should provide about 50g representative samples, some special samples about 200~1000g. The simple test needs 30 working days, and the detailed test about half a year.图片3.jpg
Sign the test contract with clients before the mineral dressing test, and make sure dressing process to test
II Testing process
1. Chemical Lab of Mineral Dressing Research Institute analyzes the material components (ore structure, mineral and types of ore) and chemical properties (elements, the particle size screening, density, ore relative grindability) of crude ore, and gets some data for the subsequent beneficiation test.

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2. After the working of Chemical Lab, Mineral Dressing Research Room takes the mineral beneficiation test which tests the optimum conditions of dressing process. 
III Test results
After finishing all the tests, Mineral Dressing Lab writes a detailed “Mineral dressing test report” by summarizing the test process. In the last part of test report, the optimum technological process and technological parameters are presented.
Engineering Design
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Three parts of mine design: feasibility study, preliminary design and construction plan
The key of mine design is all must be established on the basis of detailed investigation, and therefore Chaeng Mine Design Institute will firstly take a comprehensive field study to the mine of clients including the crude ore for dressing plant, site, water, electricity, traffic, geography, etc..
These investigation contents need the cooperation of geology, mining, ore dressing, smelting, machinery, civil engineering, electric power and other departments
I Feasibility study
In all the work of the working group to carry out, investigation, data collection and plan optimization is the most important basis for selecting plant construction scheme. For these important parts, working group requires different professional division and cooperation, including:
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1, Geological specialty
2, Mining specialty
3, Mining machinery specialty
4, Civil engineering specialty 
5, Electric power specialty
6, Mineral dressing specialty
II Preliminary design
After "Feasibility study report" approved, Mine Design Institute starts preliminary design and comes up with the design of dressing plant construction. Design mainly involves: dressing, general layout, electric power, communication, civil engineering, environmental protection, water supply and drainage, tailing, safety and fire protection, investment estimates, economic benefit. For the improvement and extension enterprises, the preliminary design will illustrate the status, characteristics, plant, main problems, utilization of main buildings and equipment.
III Working drawings                                                         2、立磨磨盘、磨辊及摇臂已吊装到位_副本.jpg
When the preliminary design is approved, Mine Design Institute starts to design working drawings. Every aspect of dressing plant needs a lot of construction drawings (generally, over 100 working drawings), such as civil construction. Engineers of Chaeng Mining Institute are numerous with rich experience and drawing speed. When the working drawings completed, the designers must hand the drawings over to construction commanding officers, especially, the notes, strict regulation and important content.

Vertical roller mill innovations of Great Wall Machinery

September 4 to 5, the 11th G20 Summit will be held in Hangzhou, China. The theme of the summit is “build innovative, dynamic, linkage and inclusive world economy” and the summit lists “blueprint of economic growth by innovation” as a key issue for the first time.CHAENG (Great Wall Machinery) constantly extends product and industrial chains with the concept of technology and science first, especially paying attention to the development of high value-added and high-tech products with the feature of energy saving and emission reduction. Our company has won the important results in the fields of vertical roller mill, tube mill, rotary kiln, etc., forming the core competitiveness of company itself, which consolidates the foundation for our company to become the domestic first-class grinding system comprehensive service supplier.
Innovations of CHAENG
Technologies innovated by CHAENG obtain Utility model patent certificates issued by State Intellectual Property Office
A kind of feeding device applied in vertical roller mill (patent number: ZL 2015 2 0349738.9): effectively reduce the power consumption of belt conveyor transmission and civil engineering cost of system and allow vertical roller mill to run smoothly at the same time.
A kind of powder selecting device applied in vertical roller mill (patent number: ZL 2015 2 0349704.X): improve more than 15% of efficiency and reduce 5% of power consumption.
A kind of dismounting device for taper sleeve of grinding roller (patent number: ZL 2015 2 0349716.2): effectively improve the efficiency of dismounting taper sleeve of grinding roller and reduce dismounting cost.
φ4.2×13m double slide ball mill (patent number: ZL 2010 2 0285841.9):fundamentally solve the problem in like products that “cannot operate constantly because of overheat of sliding bearing at the discharge end”.
Innovation for intelligent control device of vertical roller mill
Intelligent control device of vertical roller mill allows the operator to perform statistical data of the equipment and operate at any time according to situations in the field, which is adaptable, easy to operate and reliable to use. It can ensure the smooth running of vertical roller mill. The device supports internet remote operation, human-computer interaction of which is accurate, convenient and reliable.
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Design for the belt plate of rotary kiln
By reference to relevant technology and combined with production technology department, CHAENG replaces “floating plate” of rotary kiln by “replaceable plate”, which is convenient for manufacturing process and improving 20% of production efficiency. This design obtains users’ consistent high praise.
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"Multi-purpose vertical roller mill"
Multi-purpose vertical roller mill with high efficiency and energy saving means that only one vertical roller mill can achieve the grinding of various materials (cement clinker, auxiliary material and slag particles admixture, etc.). This kind of vertical roller mill has been used in the yearly output of 1 million tons cement/ 0.6 million tons slag powder production line and operation effect has exceeded exceptions after 100 days’ operation.
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In the future, CHAENG will continue to cooperate with design institute of building materials, colleges and universities and well-known building materials machinery experts to enhance the quality of the product through innovation and research and development to provide high value-added equipment for customers and give more value for the investment of customers!

Great Wall Machinery steel casting node cases

1. Project one: in 2014, the project of Shanghai Jinsha River Pedestrian Overcrossing orders 6 tons upper chord nodes with ZG20Mn5 material and intersection node with steel structure manufactured by our company is used in this project. In order to avoid the large stress of node caused by welding intersection and inconvenience of welding, cast-steel node is selected in the design, which requires material performance of cast-steel node should be equal to or better than Q420QD, wall thickness of cast-steel node should be no less than 40mm, and the minimum length of cast-steel bar should be no less than 1 meter.
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However, all kinds of demanding requirements for Great Wal Machinery are the power to process high-class steel casting node. According to properties and technical requirements of Shanghai Jinsha River Pedestrian Overcrossing, Great Wal Machinery improves the casting technique of cast-steel node and finally manufactures the satisfactory cast-steel node for customers.
2. Project two: in 2013, Hangzhou Olympic Sports Center orders 55 tons steel-joining nodes from Great Wal Machinery. Design period of Hangzhou Olympic Sports Center is 100 years, belonging to the premium and large sports construction project. Awning with steel structure is lotus petal shape. There are many bars converging on the node between petals, the structure and force condition of which is complex. Single node has the features of large size, high strength of material and heavy weight. Thus, it need to find a large-scale foundry with advanced casting equipment and mature casting technology to be the supplier of node of the whole project. After careful comparison, construction party of Hangzhou Olympic Sports Center finally chooses Great Wal Machinery to manufacture all cast-steel nodes used in the project. On the one hand, Great Wal Machinery owns the domestic advanced testing equipment and inspection equipment, which can reach secondary inspection level; on the other hand, Great Wal Machinery has many successful cases in cast-steel node processing field to use for reference.
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3. Project three: in 2011, Huai’an Stadium orders 4 tons arch springing steel nodes from Great Wal Machinery. Sculpt of Huai’an Stadium is novel, attractive and majestic, which is one of the few domestic large-span cable structure stadium. Because of novel structure, arch springing steel node of which adopts widely used cast-steel node at present, which has the high requirement for casting technology.
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The application of cast-steel node produced by Great Wall Machinery in many buildings with steel structure also lays a foundation for this cooperation. This time, construction party of Huai’an Stadium comes to Great Wal Machinery to make an on-the-spot investigation and sign the cast-steel purchase contract with Great Wal Machinery immediately. According to the requirements of construction party of Huai’an Stadium, Great Wal Machinery makes the special treatment in the casting process of node with steel structure to ensure the quality of cast-steel node.
After the completion, with excellent design and reliable quality, Huai’an Stadium wins the 2012 annual “Jingang Award” and “2013 Gold Award of Construction Steel Structure of China (national prime-quality project)”, which proves that nodes manufactured by Great Wall Machinery meet the standards of national prime-quality project.
4. Project four: in 2011, Karamay regional digital network control center orders 5 tons nodes with steel structure from Great Wall Machinery. Because of Karamay located in Xinjiang, where is snow-prone area in China, buildings in this area must have the ability to withstand earthquake, snow and large temperature difference. As the core part in steel structure – node should have good mechanical property to ensure the stability of the whole steel structure.
At the beginning of construction of Karamay regional digital network control center, delegates of construction party comes to Great Wall Machinery to make an on-the-spot investigation, on the one hand for getting to know the strength of Great Wal Machinery, on the other hand for seeking for cooperation. Great Wal Machinery designs a set of feasible technical solution for matched cast-steel node of Karamay regional digital network control center and delegates of construction party is satisfied for that. Thus, large node product manufactured by Great Wall Machinery finally achieves the desired effect. To some extent, we can say that nodes produced by Great Wal Machinery improve the reliability and stability of the whole steel structure.
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Progress of Indonesia annual output of 0.3 million tons nickel slag production line

It is reported that all equipment and parts have been shipped to Indonesia on May, 11, 2016 for annual output of 0.3 million tons nickel slag production line which CAHENG (Great Wall Machinery) will construct for Growth Steel Group. Currently, project design, civil engineering and equipment manufacturing has finished smoothly and equipment installation and debugging is coming to an end.
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Project overview:
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Because of the feature of energy saving and environmental protection of vertical roller mill manufactured by CHAENG, and after many times of visits, in November 2015, annual output of 0.3 million tons nickel slag production line contract is signed between Growth Steel Group and CHAENG.
Indonesia annual output of 0.3 million tons nickel slag production line is 2.0 updated version of CHAENG’s production line turnkey project and GRMS33.31 vertical roller millis used in this production line.
Process improving:
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Figure: Drawing of installed dust collector
Vertical roller mill manufactured by CHAENG sets crushing, drying, grinding, powder selecting and transporting in one with the advantages of high grinding efficiency, strong drying ability, easy to adjust product fineness, low noise, low electricity consumption, simple technological process, little wear, freight cost saving, etc. CHAENG has been the leader in the field, while we are not content with this and our technicians take dust treatment for the whole system and adopt closed production method from windrow to finished product, which on the one hand can eliminate most of the dust to achieve the purpose of dust collecting and environmental protection; on the other hand maximize the value-added service of new system.
Environmental protection design:
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Figure: Drawing of installed blue vertical roller mill
The color of the equipment manufactured by CHAENG is gray previously, showing a majestic momentum. However, with the adjustment and change of industrial structure, the requirement of environmental protection occupies a greater voice in industrial field. CHAENG makes a great adjustment this time: the main color of the equipment is lake blue, supplemented by the corresponding light blue and white. The three colors run through the whole production line. New color will highlight highlights and reflect the requirement of environmental protection, which shows the improvement of CHAENG’s technology and resolution to respond the national environmental protection requirement.
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The completion of Indonesia nickel slag production line marks that export of turnkey production line project of CHAENG has a good beginning and to some extent, it provides an opportunity for CHAENG and Growth Steel Group to smoothly start international cooperation on slag recycling project at the same time.

How much do you invest in the equipment of slag powder production line?

CHAENG (Great Wall Machinery) is the world-class grinding system integrated service supplier, specially providing the “turnkey” service of daily output of 20-120 tons of slag powder production line, steel slag powder production line and nickel slag powder production line for customers in china and abroad. Currently, CHAENG has own more than 100 projects of slag powder/ steel slag powder/ nickel slag powder production line worldwide including Growth Steel Group, Hebei Aosen Group, Shanghai Baosteel Group, Henan Mengdian Group, etc. Great Wall Machinery has been the leading brand of GGBS turnkey project!
How does CHAENG expand the market step by step? For this question, we must mention that in order to popularize slag powder production line, CHAENG invests RMB 50 million in 2010 and constructs a yearly output of 0.6 million tons slag powder production line by itself.
The showcase production line of CHAENG produces 0.6 million tons slag powder yearly, main product of which is S95 slag powder. GRMS46.41 slag vertical roller millmanufactured by great wall machinery is used in this production line, which introduces the technology of Tianjin Design Institute, adopts international advanced and proven vertical mill process integrating drying, grinding and powder selecting and applies DCS remote central control system equipped with efficient and energy-saving dust collector and equipment. Dust content in stack gas is lower than that of national emission standard and process technology and equipment has reached the international advanced level.
How much do you need to invest a slag powder production line? Please click and consult online customer service on the right side.
Well, how does the quality of slag powder produced by the slag powder production line of CHAENG?
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According to the head of CHAENG, slag powder is mainly used to be blended with cement and concrete to enhance the long-term strength of cement and concrete and improve the appearance of concrete, making it smooth and high brightness. It realizes the recycling and value-added exploitation of smelting waste of iron and steel enterprises and no longer consumes new resources, which is a green environmental new type building material product.
Pouring quantity of concrete of construction in process which GGBS manufactured by CHAENG and used to is accumulated up to 0.03 million cubic meters.

Clinker production stage in cement production line

Clinker production is the most energy intensive stage in cement production line, accounting for over 90% of total industry energy use, and virtually all of the fuel use. Clinker is produced by pyroprocessing in a large rotary kilns. These rotary kiln systems evaporate the inherent water in the raw meal, calcine the carbonate onstituents , and form cement minerals . any different fuels can be used in the rotary kiln. In these rotary kilns a tube with a diameter up to 8 meters (25 feet) is installed at a 3-4 degree angle that rotates 1-3 times per minute. The ground raw material, fed into the top of the kiln, moves down the tube counter current to the flow of gases and toward the flame-end of the rotary kiln, where the raw meal is dried, calcined, and enters into the sintering zone. In the clinkering zone, the combustion gas reaches a temperature of 1800-2000°C (3300–3600 °F). While In a wet rotary kiln, the raw meal typically contains approximately 36% moisture. These kilns were developed as an upgrade of the original long dry kiln to improve the chemical uniformity in the raw meal. The water is first evaporated in the rotary kiln in the low temperature zone. The evaporation step makes a long kiln necessary. The length to diameter ratio may be up to 38, with lengths up to 230 meters (252 yards). The capacity of large units may be up to 3600 tonnes (3970 short tons) of clinker per day. Fuel use in a wet kiln can vary between 5.3 an G In a dryrotary kiln, feed material with much lower moisture content (0.5%) is used, thereby reducing the need for evaporation and reducing kiln length. The first development of the dry process took place in the U.S. and was a long dry kiln without preheating . Later developments have added multi-stage suspension preheaters or shaft preheater. Pre-calciner technology was more recently developed in which a second combustion chamber has been added between the kiln and a conventional pre-heater that allows for further reduction of kiln fuel requirements. The typical fuel consumption of a dry kiln with 4 or 5-stage preheating can vary between 3.2 and 3.5 GJ/tonne clinker, electricity use increases slightly due to the increased pressure drop across the system. A six stage preheater kiln can theoretically use as low as 2.9-3.0 GJ/tonne clinker. The most efficient preheater, pre-calciner kilns use approximately 2.9 GJ/tonne clinker.
rotary kiln
Once the clinker is formed in the rotary kiln, it is cooled rapidly to minimize the formation of a glass phase and ensure the maximum yield of alite formation, an important component for the hardening properties of cement. The main cooling technologies are either the grate cooler or the tube or planetary cooler. In the grate cooler, the clinker is transported over a reciprocating grate through which air flows perpendicular to the flow of clinker. In the planetary cooler (a series of tubes surrounding the discharge end of the rotary kiln),the clinker is cooled in a counter-current air stream. The cooling air is used as secondary combustion air for the rotary kiln.

Small design innovation for cement grinding mill to avoid troubles

(Great wall machinery is one of the domestic first-class grinding system integration suppliers. With the advantages of technology, equipment and brand of ball mill, rotary kiln, vertical roller mill for nearly 6 years, Great Wall Machinery devotes itself to carry out business service in many fields and gradually expend the business mode including EPC project, financial leasing and spare parts supply as the increasing maturity of single equipment and turnkey project, successfully realizing the change from manufacture to manufacture + service.)
It’s hard to avoid irregular faults occurred on the cement plant equipment. What troubles has your cement grinding mill occurred? As an operator of the cement plant equipment, you must summarize and accumulate the experience from all aspects all the time and optimize the design for the specific details of production line to avoid equipment occurring the faults. Now let’s see the faults occurred on the cement grinding mill in a domestic cement plant and what methods they adopted to improve and enhance it to ensure the normal operation of the equipment.
Abstract: the type of the main motor of the cement grinding mill in a cement plant is YRKK800-8, power 2500kW with Babbitt metal bearing, material of which is composed of tin, lead, antimony, copper, etc. with the feature of soft texture and low temperature. The highest operation temperature of Babbitt metal bearing of control bearing bush is 100℃. In order to protect bearing bush, the upper limit value of temperature protection is set to 63℃. Once exceeding the setting value, DCS will control the main motor of the mill and stop it. Lubricating oil station of main motor of the mill is equipped with two pressure switches and the pressure are respectively set to 0.12MPa and 0.2MPa. The normal value of oil supply pressure when the oil station operates is about 0.25MPa. If oil supply pressure is lower than 0.2MPa, emergency bearing oil pump will be started to allow the oil pressure to meet the lubrication demands of bearing of main motor; if oil supply pressure is lower than 0.12MPa, there are troubles in lubrication system. Oil pressure signal interlocks main motor of the mill and stops it to avoid the high temperature burning the bearing bush.
1. Fault phenomenon
On January 7, 2015, No. 2 control room of cement grinding mill of a cement plant trips because of the fault of DCS control power supply, which leads to the missing of DO signal of cement grinding mill and causes the tripping of all low-voltage equipment of No. 2 cement grinding mil. Staff finds that main motor of the mill is still operating as routing inspection and presses the emergency stop button on the spot. After inspected by electrical personnel, it finds that rotor journal of main motor wears seriously and front and rear bearing bushes are burned out due to high temperature. After the fault of DOS system leading to the tripping of lubrication oil station, oil pressure lower than 0.12MPa doesn’t stop the main motor and bearing bush with high temperature nor stop it, which is the root cause for serious wear of rotor journal and burn-out bearing bush.
2. Analysis for fault reason
Main motor of cement grinding mill is high-voltage electrical equipment, whose principle of start-stop circuit is shown in figure 1.
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Figure 1: diagram of principle of start-stop circuit of main motor of cement grinding mill
As shown in figure 1, motor-driven relay K1 and K2 of DCS system respectively pulse trigger switch closing and switch opening to stop and start the main motor. After power-loosing of DCS system, switch opening commands that K2 cannot stop the main motor; on the other hand, both chain jump stop signal of low oil pressure of oil station and overheat of bearing bush control opening coil through DCS output. DCS fault cannot trigger switch opening of breaker of service truck, which lead to the failure of protection system and trouble parking of equipment.
3. Fault handling
Switch-opening circuit of main motor of the mill is controlled by soft chain of DCS system, while the influence of DCS fault on equipment is not fully considered at design. However, hard chain can solve the problem. For hard wire, low oil pressure signal of lubrication oil station is only need to be led to the switch-opening circuit of high-voltage board of main motor of the mill. While the lubrication oil station is set up on the spot, which is far from the high-voltage board and it is time-consuming and strenuous with high cost if directly install the cable. According to the site situations, electrical maintenance personnel decide to make use of the feature that the lubrication oil station is close to the emergency stop button box of main motor to parallel signals and then send them to high-voltage board. Temperature signal of bearing bush is no modification for gather the analog quantity. Control principle diagram after modification is shown in figure 2.
As shown in figure 2, realize the soft chain and hard chain control for main motor through adding intermediate relay in the control box ALC2 of lubrication oil station. Auxiliary contract of K3 is connected with DI of DCS to realize the soft control for switch-opening coil of equipment and auxiliary contract of K4 is paralleled to button box ALC1 near the main motor to directly act on the tripping circuit of the equipment and realize the hard control for switch-opening coil. After modification, it is successful to separate the switch. After that, the same modification is carried out for lubrication oil stations of grinding head, grinding tail and main reducer and low oil pressure signal of all oil stations is paralleled to switch-opening circuit in figure 2. In this way, fault of any oil station can stop the main motor timely and fault trip reliability of main motor of the mill is increased through soft chain and hard chain.
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Figure 2: Diagram of control principle of main motor after modification
4. Conclusion
This accident exposes the hidden dangers in the design of equipment. Interlocking relationship among equipment with different voltage grades should be paid special attention in the process of design. Consider the influence of different faults on the equipment and timely find the control dead sector of equipment operation and parking to improve the design and maintain safe operation of equipment and safe production of enterprise.

Introduction to high manganese steel jaw plate of jaw crusher

Moving jaw of jaw crusher is also called jaw head or jaw back. Jaw plate is also called toothed plate, which is the key wear-resistant part of jaw crusher. A set of jaw plate is usually composed of two parts, namely, the moving jaw plate and fixed jaw plate. Jaw plate is the major component of jaw crusher, including moving jaw plate and static jaw plate. There are different sizes according to the different types of jaw crusher, which generally use the material of high manganese steel.
Materials used: Mn13, Mn13Cr2, Mn18Cr2 (namely super high manganese) or special dosing according to working conditions. Jaw plate of jaw crusher manufactured by Great Wall Steel Casting Company is exquisite with rigorous dosing and excellent heat treatment technology. Service life of jaw plate manufactured by our company is higher than 50% of that of the similar products.
Composite jaw plate
Cast by high performance new composite material, the service life of composite jaw plate is more than three times higher than that of ordinary jaw plate, which breaks the record that the service life of new material wear-resisting castings are only 1.5 times higher than that of manganese steel castings. Composite jaw plate, new composite rolling wall and so on transformed by scientific and technological achievement have been recognized by many industries with poor working conditions, such as mining industry and metallurgical industry.
Jaw crusher is used in many fields. Because of its different specification, feed particle size and hardness of materials, the extrusion and impact force to jaw plate is also different. Great Wall Steel Casting Co., Ltd manufactures jaw plates with various specifications and models by high manganese steel and metamorphic high manganese steel respectively to meet the need for jaw crusher in different working conditions.
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Structure and features
1. Use manganese steel bonded carbide to make high wear-resisting degree and long service life.
2. Use cold hardening technology to make high hardness.
3. Carry out water toughening to avoid natural phase change in the use and leading to poor performance.
4. Strictly spot checked by laboratory and quality testing department before leaving the factory, so the quality of the product is assured.

Help cast steel gear processing of CHAENG go international

Future development trend of industry is the focus of many enterprises, including casting industry and cast steel gear casting industry. Supply and demand situation is not optimistic in cast steel gear casting industry in recent years. Thus, the development of next few years will be the focus to pay attention.
I think if we want to know the future development trend of cast steel gear casting industry, we need analyze the following aspects:
1. Market research. Only by market research can we grasp the first-hand and real information of market in the first time, which is the base to analyze the future development trend of cast steel gear casting industry.
2. Refer to the basic information reported by related authorities and materials provided by professional research units. Authorities include National Bureau of Statistics, General Administration of Customs, related industry associations and domestic and abroad related newspapers and periodicals. The information reported by them is professional, authoritative and reliable. The information has a significant influence on analyzing current situation of domestic large cast steel gear industry, market supply and demand and industry chain.
3. Refer to the recent development situation of key enterprises in industry, whose development has a certain representativeness. Understanding the development of these enterprises means that master the most of market development situation of industry.
In order to allow large gear processing factories to better strive in cast steel gearmarket in an impregnable position, they must more comprehensively and accurately grasp the development situation and future trend of cast steel large gear industry. Take a panoramic view of the situation and pay attention to details to know development trend of industry.
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As a domestic first-class cast steel gear casting factory, CHAENG not only grasps the development trend of cast steel gear industry but also follows the trend of industry development to update technology and improve processing ability.
In addition, CHANG has made a proud achievement in cast steel gear casting. The reason is that there is a large number of talents to be the support. Our company creates a branch of inter-disciplinary talents with the ability of scientific and technological innovation and operating management through implementing the talent strategy to strengthen the construction of talent team. And our company continuously strengthens the function training of whole staff and improves the skills of whole staff.

What is the main produce equipment of Coal grinding station ?

Coal grinding station main production equipment include: coal mill, coal transportation equipment, unloading equipment, dispensing equipment. pulverized coal mill system is the core of the coal grinding station.
However, due to the characteristics of explosive coal dust, and the fineness requirements, a lot of coal grinding plants their technical requirements are higher during the coal preparation.
Chaeng (Great Wall Machinery Co., Ltd)as a domestic first-class grinding system integration provider committed to the research and production of coal preparation systems over the years, Chaeng coal preparation systems project engineer for us a detailed introduction.2013HMQcguSlxK.jpg
1.coal fineness of coal grinding plants must be guaranteed
For power plants in terms of pulverized coal boiler, coal fineness not only affect the operation of the larger economy, but also have an important impact on the safe operation of boilers, especially those burning lean coal and anthracite boiler even more so. If coarse pulverized coal, it can easily lead to fire boilers, coking, high-temperature corrosion, Reheater Tube Explosion, combustion efficiency and low wear and tail heating surface a series of questions.
Only the finer coal,which can catch fire and burn rapidly, the smaller the loss of incomplete combustion boiler, a corresponding order to improve the efficiency of the boiler (if the boiler is maintained at the fineness of pulverized coal economy running, each 600MW boiler can save Billions of tonnes per year coal).
2. coal grinding plants must use a variety of measures to prevent explosions in coal preparation process
In the grinding system, pulverized coal is transported by a gas, gas powder mixture is likely to encounter a spark caused an explosion pulverized coal. In a closed system, the pressure generated when coal dust explosion up to 0.35MPa, so in the event of an explosion, the consequences are very serious.
So, how to prevent it?
(1). the higher the temperature of the gas mixture powder, the more explosive. So pulverizing system operation should strictly control the mill outlet gas temperature of the powder mixture. The water is often reflected in the coal mill outlet air temperature, in actual operation, the coal mill outlet air temperature should be selected according to the different powder mixture of coal.
(2). the pulverized coal pulverizing system should be installed in a conduit , which have a certain inclination angle, trying not horizontal pipe, no dead ends, the flow rate of gas powder mixture should not be too low, in pulverized coal pipeline, reduce throttle deposited to prevent the accumulation of pulverized coal spontaneous combustion caused the explosion.