外文翻译-在煤矿井筒中关于水垢切割机的研究和开发

翻译部分JOURNAL OF COAL SCIENCE &ENGINEERING(CHINA) ISSN 1006-9097pp 7882 Vol.10 No.1 June 2004Research and development on cutting scale machine in the coalmine shaftREN Bao-cai (任保才)(The Mechanical Engineering Department, Jiaozuo Institute of Technology, Jiaozuo 454000, China)Abstract The deposit scale in the coal mine shaft usually causes serious accidents, such as making rope broken, cage seized or dropped. To solve this kind of problems, the research of the cutting scale mechanism was made, and a new type of removal scale equipment was made with using imported hard alloy material. The cutting experiment and actual cutting show that it can adapt to abominable condition in the shaft, such as narrow space, wet and excessive shaft crevice water and so on, and can work safely and reliably, and has high cutting scale efficiency. It can also cut out the deposit scale in the circular section of shaft.Key words deposit scale in shaft wall, cutting scale, cutting mechanism, cutting scale machineIn the service shaft of Tongye Coal Mine of Anyang Mining Bureau, the shaft crevice water is excessive, and in water there is a large of lime stone deposit, which leads to large scale on the shaft wall through long time, which is 300 mm in thickness. The initial design diameter of the shaft is D=3.2 m,the clearance between the cage and the shaft wall is 200mm, but now the projecting part of cage has been embedded in the scale about 100 mm, which is shown in Fig.1. Once in a winter, the shaft crevice water frozen and seized the elevating cage, this made the winding rope broken suddenly, and led the cage to drop into the bottom of shaft, which caused large economic losses. The scale in the shaft wall is always one of the hard problems puzzling this coal mine. The study about the scale is more than 100 years, and great progress have been made 14,which is presented mainly in two different aspects.The first is to control and slow the scale to form,and study the principle how the scale is formed and the dynamic model that the scale is separated out and sunk58 and so on. Using chemical method,clear out the scale by pretreatment and intenerate to water, such as adding antifouling composition and so on. The second is to clear out the scale existing on the shaft wall, mostly using chemical, physical9,10, abrasive jets methods and so on. But these methods have not been found to be used in the aspect of cutting scale on the wall of the shaft11. The author puts forward a new scale removal method based on the cutting experiment of the scale sample,and has developed a cutting scale machine type SGQ-1. The parting tools are made of an imported hard alloy material, and the door frame operating mechanism is designed to adjust the tilt angle of the table, all of them can improve the adaptation of cutting the scale on the circular section of shaft wall.Fig.1 The scale in the shaft wall1 Analysis of the condition of cutting the scaleThe water resource of the formed scale on the shaft wall is ground water, which flows into the shaft through the cracks on the shaft wall, by the long-term more than 30 years accumulation, the thickness of scale on the shaft wall is above 300 mm. This shaft is more than 180 m deep, which has bunton beams every 3 m. Only on the shaft wall which is about 40 m in depth from the ground surface, here are no shaft crevice water and scale, but on the lower part of the shaft wall, button beams, cables, water pipes, wind pipes and so on, there are serious scale. The outer diameter of the cable laying down the shaft 30 years ago is 70 mm, but now has increased to about 120 mm, which is shown in Fig.2.The results of the assay and analysis of the scale on the shaft wall 12 are shown in Table 1.Fig.2 The scale on cable(a) Comparison of the scale on cable; (b) Annual ring type scaleTable 1 Chemical composition of scaleTable 1 shows that the shaft scale is mostly made of limestone, silica sand and cementations adhesion and so on. The reason is that the limestone dissolved in the shaft crevice water has gradually formed milky lap descent sediment by long-term accumulation. And the sand with coal and dirt blown into the shaft from ground have attached on the shaft wall together. As a result, these materials have interacted each other to form the scale.The section of the scale that shows annual ring type texture can prove this point. Hardness value of the scale is equivalent to the rocks hardness value f 5, and it has high wear-resistant and its one-way tensile strength is more than 24.8 Map. When we cut the scale, we cannot affect the normal lift and production of the coal mine. Above all, the scale in this shaft is very serious, the difficulty of cutting the scale and the large amount of work, are really infrequent in our country.2 The development about cutting scale Machine 2.1 Machine structure of cutting scale machineTo different basal body of scale and situation, there are different scale removal methods, which directly affect the decision of the machine structure and type. If chemical clearing methods are used, because there is a lot of shaft crevice water, it will lead to affect production and high cost and so on. If the high-pressure pure water jet is used, the pressure should be more than 60 MPa, it is difficult to bend hose in this so high pressure in the narrow shaft, and the high-pressure water is easy to rebound to hurt the operator. Although abrasive jets can low the pressure, it is difficult to supply and recovery the grind in the shaft. If we adopt manual method to cut the scale in the shaft, every team needs four people, who clear out 15 d every day, the cleared areas are about only 2 m2, which is a low efficiency, large work strength and bad security.Through the analysis, comparison and demonstration of many aspects, finally, we selected the method of using imported hard alloy tools to the cut scale, and developed the cutting scale machine. The structure principle of the cutting scale machine is shown in Fig.3. Its main technical parameters are as follows: the lengthwise travel rate of table is 0.33 m/min, crosswise feed rate is 0.10.3 m/min, the tilt angle is 090; cutter head rotational speed is 2 850 r/min, the diameter is 350450 mm; the kerfs breadth is 36 mm; the power is 5.5 kW; voltage is 380 V; the weight of the machine is 500 kg.Fig .3 The structure principle of the cutting scale machine1- Basement; 2- Framework; 3- Lengthwise travel mechanism; 4-Cross wise feed mechanism; 5 -Cutting table; 6- Electric motor; 7-Cutter head 2.2 Action processWe selected the service shaft of Tongye Coal Mine to experiment, the cutting scale machine which is fixed on the flat-platform body was loaded into a cage (It may also be fixed on the cage by using special basement to work), and fixed on the rail of the bottom of the cage with snap gauge.During the lift spare time, put the cage down to the position where the scale should be cut in the shaft, and then stop. Every time, two worker are needed in the cage, there into, one operates the machine, another answers for safety and warship, they can exchange their work every one hour.First, we use snap gauge device to fix the cage, and then randomly select a cutting scale position of the working table in the range from zero degree to ninety degree, after it is fixed, we may start it. We operate length feed and crosswise feed device to control amount of feeds. The machine achieves double coordinates linkage, which dont occur interference in the active state. After doing one cut from up to down, we may adjust the cutting space between 50 mm and 120 mm, and then repeat above the cutting process circularly. When the space between the two cuts is less than 100 mm, scale will breakout automatically after being cut by high-speed cutter head. We adequately use shaft crevice water to cool the electric motors and cutting tools. The cutting reaction force of the machine that acts on the shaft wall by the base frame, flat wagon, cage, guide and guide beam, makes the machine gain balance in force, and assure the machine run steady and safely.3 Analysis about the cutting principle 3.1 Analysis about the cutting principle of toolsTo the difficult-to-cut scale with high hardness, strength and abrasiveness, whether it can be cut is very important to the selection of cutter. Comparing several cutting experiments with several different cutters in lab shows that the cutter made of the imported hard alloy has high efficiency.In the process of cutting scale, the hard alloy cutter, besides the linear feed movement of the common cutter, it also rotates round its self-axis. The action of cutting scale is mainly considered as extrusion, crush, sliding friction and so on10,13,14.The direction and speed of feed, the speed and depth of cut, the condition of cool and so on, will bring different effects to the cut efficiency and the life of the cutter. In order to simplify the problem, we randomly take a piece of cutter to analyze. The cutting scale machine use the cutting edge of the high-speed rotating flat hard alloy tools to crush the scale, generally, which also has the wedge function.Generally this crush belongs to the brittle crush. The kerf of the cutter emailed on the scale mainly occurs during the deformation step that the cutter cuts the scale.From fracture mechanics 15, it is known that the stress condition in the distance r from crack tip may be expressed as follows:where, r is the distance form the crack tip to an arbitrary point; q is the angle between the line connected the crack tip to the point and horizontal line; K1 is the fraction stress intensity factor type I.The above formulas explain the cutting and crush function that the cutter cuts the scale, that is to say, when the tool nose of the cutter just touches the scale, the cutter travels forward and generates the squeezing action to the make scale generate elastic deformation and stress. The necessary condition of crack to develop in the point (r,0) is that the stress of this point must be equal to or exceed the critical stress of scale sc, namely, sc=sy1. In the formulas, sy1 is the stress that the mechanical cutter must apply to the scale. While the cutter goes forward constantly, the cut resistance also increases constantly, when the deformation of the scale reaches the boundary value, the shearing stress makes the scale generate cracks, which expand, impenetrate, and intersect unsteadily, finally, lead the scale to generate brittle fracture, and the scale starts to break and fall down, at the same time, the cut resistance decreases rapidly. It is shown in Fig.4.Fig.4 The principle of cutting scale1 Cutter head 2 Cutter 3 Scale 4 Shaft wall 5 Crack3.2 Analysis about critical cutting speed and abrasive coefficientWhen the high-speed rotational cutter head cuts the scale, besides having squeezing function, there is the function of sliding friction. We may clearly see every piece of scratch with orders in direction from the scale kerfs or cutting section Fig.5.Through zooming in the cutting section further, we find many newborn cracks, the reason is that the shearing stress which the cutting surface suffers under the frictional force increases continually, when it exceeds the frictional stress value of scale, generate dislocation motion, and finally lead to icrocrack, but it has relation to the critical cutting speed and abrasive coefficient. Cutting speed is a discriminant parameter of the cutter life, together with abrasive coefficient, are the factor that leads the cutter temperature to rise. To hard alloy, because of it exists the critical temperature, when the temperature exceeds this temperature, it will soften. The abrasives phenomena caused by abrasiveness mineral substance becomes more serious, that is to say, there is also the critical cutting speed of the scale, when the cutting speed exceeds it, the wear of the cutter will increase obviously 14,16,17. So a good cooling condition is an important factor to decrease the wear of hard alloy and increase the life. The abrasive coefficient has relation to the abrasiveness mineral substance content, the grind size and the strength of settling matter. The experimental results are shown in Fig.6, from it, we may get empirical formula as follows:Fig.5 The shape of the scale chipFig.6 The relation of the cutting speed with abrasive Coefficientwhere, vl is the critical cutting speed; K is a constant that has relation with the cutter shape and the critical temperature of hard alloy; u is the abrasive coefficient; e is the napierian base, thus it can be seen that the critical cutting speed changes along the logarithmic curve.Generally, we should avoid making the cutting scale machine to run in the condition that exceeds the critical cutting speed, or it will increase the wear of the cutter and decrease the life, and so much as makes the cutter fracture.4 ConclusionsThe cutting scale experiment in the service shaft of Tongye Coal Mine shows that this machine not only can adapt to the situation of narrow, wet and excessive shaft crevice water, but also can use excessive shaft crevice water in the shaft to cool the cutter and the electric motor.(1) The efficiency made by using high efficient hard alloy parting tools to cut scale is at least ten times than the manual method.(2) The door frame operating mechanism can clearly cut the scale in the circular section of the shaft wall. When the machine doesnt run, it can be drawn back to the cage, which doesnt affect to lift normally.(3) The immersible motor and blast protection control panel can realize many protection, such as leakage, short, overpower, loss of phase, no-voltage and electromechaincal lockout, which can make the worker and the machine work safely and reliably in the shaft.(4) After the scale is cleared, the elevating condition has great improvement, which can avoid broking rope and seizing cage, assure to produce safely, and has good social and economical benefits. Furthermore, this machine may be put in the water to cut and process the granite and the marble, which are little dust, no noise and brings benefits for the environmental protection.中文译文在煤矿井筒中关于水垢切割机的研究和开发任保才(机械工程系,焦作工学院,焦作404 42454000 ,中国)摘要 水垢的积累在煤矿井中通常会造成严重的事故,如钢丝绳崩断, 罐笼卡住或下滑. 为了解决这种问题,研究水垢的形成机制时,提出了一种新型搬运设备,是用进口的硬合金材料制作. 切削试验和实际切削表明,它能够适应恶劣的情况,在竖井, 如空间狭窄,潮湿,过度轴裂隙水等条件下,能工作,且安全可靠,使用方便， 并具有较高的切削效益. 它也可以除去存在圆截面井筒中的沉积物. 关键词 矿床矿井沉淀物,去除水垢,切割机, 水垢切割机 在安阳矿务局同业煤矿副井中,井筒裂隙涌水过大, 并在水中有大量的石灰石矿井壁通过长时间形成大量水垢, 有300毫米厚度. 最初的设计的直径轴为D = 3.2米,罐笼距井壁的是200毫米, 但现在预测部分罐笼已嵌入的水垢约为100毫米, 这体现在永久性上. 在一次冬天,井筒缝隙涌水冻结和扣押在升降笼中, 这使得钢丝绳突然破裂,并导致了罐笼掉进井底，造成较大经济损失. 水垢在井壁始终是一个很大的问题,尤其是煤矿. 这项研究的时间已超过100年，已经取得巨大进展1-4 ,这主要表现在两个方面,是控制和减缓水垢的形式,并研究如何水垢的形成机理已形成,动态模型的规模是分离出来，并让其沉淀如 5-8 等. 采用化学方法,清除水垢的预处理和软化水质,例如加入防污组成等。二是明确了现在有水垢的井壁,大多采用化学方法,物理方法 9-10 磨料射流方法等. 但是,这些方法并没有发现有使用方面的水垢在墙上 轴11。笔者提出了一种新的除垢方法，即基于切削试验的样本水垢,并制定了切削机床模型SGQ-1。分离工具,是一种进口的硬质合金材料制成, 特殊的运行机制,是旨在调整倾斜角度，他们都可以提高适应切削圆形段井壁水垢的能力。图1 井壁上的水垢1 分析去除水垢的条件形成井壁水垢的水源是地下水，其中流向井筒的通过井壁裂缝, 由于长期的超过30年的积累, 厚度尺寸大于300毫米. 这个井是180多米深的,而罐道梁3米. 只有在井筒中约40米深的地表, 这里没有井裂隙水和水垢,但下部井壁,罐道梁, 电缆,水管,风管等,有严重的水垢. 外径电缆等, 30年前是70毫米, 但现在已增加至约120毫米, 这体现图2。对井壁水垢的检测与分析的结果见表1。图2 绳缆上的水垢表1 水垢的化学成分表1表明,竖井水垢主要由石灰石,石英砂等等和水泥粘附形成. 其原因是,石灰石溶解于轴缝隙水已逐渐形成乳状，与水泥沙长期积累而成. 而从地面砂石、煤与污垢对井壁高度在一起. 由于这些材料相互作用,互相配合,得以形成水垢.年轮纹理的水垢断面就可以证明这一点. 水垢的硬度值等同于岩石的硬度值f 5, 它具有高耐磨性,其单向抗拉强度大于248兆帕. 当我们削减水垢时,我们不能影响煤矿的正常生产. 首先,水垢在井筒的情况十分严重,消减水垢的困难及其工作量实在是少见. 2水垢切割机的发展 2.1水垢切削机床的机械结构不同的水垢和状况,有不同的除垢方法，将直接影响到机械结构和类型的决策. 如果用化学清洗方法,因为有很多竖井裂隙水, 这将导致影响生产和成本高昂等问题. 如果用高压水射流器，压力应超过60 MPa时, 很难弯曲软管,而且如此高的压力,在狭窄的竖井中,高压水很容易反弹伤害算. 虽然磨料射流可以在较低的压力下工作,但很难供应和回收磨轴. 如果采用手工方法来削减竖井的水垢,每队必须有4人, 谁清理15 天,每天清理的范围大约只有2平方米. 这是一个低效率,大强度的工作，而且安全性很差. 通过分析,比较和论证多方面的,最后, 我们选择的方法是,用进口硬质合金工具来切削水垢, 并开发了相应的切割机. 切削机床结构设计原理如图3. 其主要技术参数如下: 纵向出游率表为0.3 3米/分钟,横向进给速度为0.1 0.3米/分钟,倾斜角为090 ; 刀头转速是2850转/分钟,直径为350450毫米; 切割宽度为36毫米; 该功率为550千瓦; 电压为380伏;机器的重量是500公斤.图3 水垢切割机的结构原理1地下室; 2框架; 3侧切进给机制; 4横向进给机制; 5切割表; 6电动马达; 7刀头2.2 动作过程我们挑选同业煤矿副井实验，水垢切割机是固定在扁平平台,机体被装入一个笼子(也可固定在笼子里在特殊的地下室来工作) , 并固定在钢轨底部的罐笼上.在电梯空余时间, 把罐笼传到了在竖井应该削减水垢位置上,然后停止. 每一次,两名工人需要在笼子里,其中,一个操纵机器, 另一个负责安全