Application of Electrical Haulage In-web Shearer on Working Face of Ultra-thin Coal Seam with Large

2018-02-05 0 Views (525)

The paper introduced application range, mechanical part, electrical control part, main functions and actual application of MG110/130-TPD model electrical haulage in-web shearer on a working face of ultra-thin coal seam with large inclination .The app



 Application of Electrical Haulage In-web Shearer on Working Face of
Ultra-thin Coal Seam with Large Inclination


Abstract: The paper introduced application range, mechanical part, electrical control part, main functions and actual application of MG110/130-TPD model electrical haulage in-web shearer on a working face of ultra-thin coal seam with large inclination .The application has showed that the shearer runs stably with good mining effect and improves safety level and efficiency of production of working face .But there are still a few problems of channeling gangue and irregular running track that caused by chain haulage for further research .

 

1. Introduction

Sichuan Dazhu Coal Electricity (Group) Co., Ltd., XiaoHeZui mine is an ultra thin coal seam. Most of the coal seam thickness is 0.5-0.8m; the angle is 0°-45°. For a long time, the coal mining by blasting, collapse method roof control, retreat to long wall mining, scraper transport, single hydraulic prop, so low degree of mechanization that mining efficiency is not good. In 2006, the mine used MG100-TP type single drum coal shearer and improves the efficiency of coal mining. However, there are some problems in the operation of this type of shearer:

1. With the increase of coal hardness and coal seam inclination, the shearer will be difficult to work and loading effect becomes poor.

2. No safety brake device that the threat to the safety of production.

3. Have to carry out the machine operation, which is not conducive to the safety of the coal mining machine driver.

In view of these, Sichuan Dazhu Coal Electricity (Group) Co., Ltd. and Liaoyuan Coal Mine Machinery Manufacturing Co., Ltd have developed a new type of MG110/130-TPD model electrical haulage in-web shearer jointly. The application is showed that the shearer runs stably with good mining effect and improves safety level and efficiency of production of XiaoHeZui coal mine.

 

2. MG110/130-TPD model electrical haulage in-web shearer
2.1 scope of application

MG110/130-TPD model electrical haulage in-web shearer can working with scraper conveyor, single hydraulic prop, metal friction prop and roof-master, to achieve coal mining and coal loading in the working face of long wall mining. This machine is suitable for coal seams which dip angle is below 35 degrees, the coal seam thickness is 0.52 ~ 0.8 m, the length of the inclined longwall working face is about 120 m. And some requirements like coal hardness f ≤3, moderately stable roof, the floor undulation should not be too large, coal seam without hard inclusions. In addition, all electrical coal mining machines are explosion-proof requirements, working environments of methane, coal dust, and hydrogen sulfide; carbon dioxide concentration does not exceed the content.  

2.2 Mechanical part

The coal shearer makes up of the host body, coal loading part, composed of bottom bracket and spray cooling system. The traction part, the cutting part, the transportation-transmission device, the electric control box and the rocker arm, are all arranged on the whole casing. The traction part realizes the walking function of the shearer on the traction chain, which is mainly composed of the motor, the three stage planetary gear reducer, the guide chain wheel shaft group and the hydraulic braking system, and the max speed is 5.84m/min. The cutting part is a speed reducing mechanism between the motor and the roller, and the cutting part is provided with a torque clutch mechanism to prevent the motor from being damaged due to overload. The electric control box and the host body are welded into a whole structure to reduce the butt joint surface and improve the rigidity of the whole machine. Spray cooling system of shearer is within the inside and outside spray, the electrical components of cooling water, water hose, combined with water valve and valve and valve assembly.

Coal shearer work will have a lot of dust, and the main components (such as motor rocker,etc.) will produce high heat, therefore coal shearer set up a spray cooling system for dust and cooling to ensure the normal work.

2.3 electronic control system

MG110/130-TPD model electrical haulage in-web shearer is equipped with KXJ24 -130/1140(660) C type mine explosion proof and intrinsically safe electric control box. The electric control box adopts advanced PWM frequency conversion technology, PLC control technology and industrial computer control display technology. It has a wide range of speed regulation, large traction, non slip ability, and strong adaptability to the working face, so the operation control of coal mining machine is more convenient and reliable.

2.4 main functional features

MG110/130-TPD model electrical haulage in-web shearer is driven by single rocker arm double motors which cutting power is large. The integral casing structure, the cutting reaction force and the pulling force are all the main body of the structure, and the reliability is high. Using AC frequency conversion technology, to achieve the traction stepless speed regulation, high electric traction efficiency, high traction and reverse speed. Wide speed range (0-5.84m/s) is according to the specific situation of the working face for speed control. Remote control mode is to achieve traction and main stop function; shearer driver can be off the machine operation. The screen can be displayed on the warning, gas and other information, real-time display of operating conditions of coal shearer. The aim of the fault inspection procedures is to facilitate the analysis of equipment failure, maintenance. Adapting to different dip working face can make less floating coal. Internal and external dust spray has a cooling effect on the cutting teeth. Emergency brake device of hydraulic traction sprocket is to prevent the decline of coal shearer in special situations such as power failure emergency braking. The unit can realize the exchange of the left and right working faces, and save the cost of the unit. High climbing ability has the maximum operating angle of 45 degrees.

 

3. Field application

MG110/130-TPD model electrical haulage in-web shearer was used in XiaoHeZui Coal mine 4026(22) working face in 2009. The thickness of coal seam is 0.46 to 0.77m, with an average thickness of 0.61m, strike 22°~ 25, dip 112°~115°, dip angle of coal seam is 13°~ 43°with an average angle of 28°. The hardness of coal seam is 1 - 3 and the hardness of surrounding rock is 6 - 8. Coal seam stability is medium and 1/3 is coking coal. The mining height is 0.75m, which needs to cut partial roof, the direction length is 550m, and the inclined length is 112m. Field application at the beginning due to the performance of the mining machine is not familiar with coal mining machine, the effect is poor even can’t be used. After researched, it is determined that the use of excessive dust water (inside, outside the spray are used) and lead to the roller cannot produce coal. After reducing the water discharge of dust, the effect of coal mining was initially revealed.

It was found that although the overall operating efficiency of the coal mining machine is good, but there are some problems in the experiment.

(1) Coal shearer transport ministry of transport capacity is poor, there is a large number of floating coals transporting in increased working surface floating coal.

(2) In operation, the two ends of both ends of the bottom plate of the unit are straight and flat, and the phenomenon of the bite is appeared, which makes the load.

(3) Traction chain appears scar easily broken chain.

(4) The chain wheel adopts the full closed protection device so that protection effect is good, but at the same time it increases the difficulty of the field treatment of the fault of the traction chain.

(5) Leakage phenomenon occurred in the inner spray seal, and then water enters the gear box and leads to the deterioration of lubricating oil.

In view of the above problems, take the following measures:

(1)Redesign and replacement of the department of transportation, increased width, solve the problem of shearer transportation capacity is not enough, improve the speed of transportation, thoroughly improve the unit transportation effect.

(2)The reform of the boat shaped floor to prevent the phenomenon of cutting the bottom.

(3)Redesign of the spray sealing device to prevent the spray water seepage into the reducer.

By using the above measures to improve the shearer, the operation effect of the shearer has been improved significantly, and various technical indicators have reached the requirements of the coal mining machine operation.

 

4. Epilogue

The effects of product and mist cooling of this type coal shearer are good in ultra thin coal seam. And the emergency brake device can prevent wounding accident efficient when the coal shearer breakdown and start to slipping. That’s conducive to keep safe production of the working face. In the XiaoHeZui coal mine, the level of mechanization has increased substantially after used this coal shearer. The average daily output up to 390 T, has created a very good economic benefits.

The shearer has the following problems in the course of operation:

(1)It’s easy to channeling gangue when mining in the large dip angle working face which will threat machine operator’s safety and cannot do the parallel operation, also the production efficiency is not high.

(2)Unit using chain traction which relative to the scraper conveyor is a free body and move irregularly, there is the possibility of a broken chain down. The next step will be to further study the above issues.