2456 帶式輸送機(jī)4

2456 帶式輸送機(jī)4,輸送 Discussion about pull installation of belt conveyerBelt conveyer also claimed rubber belt conveyor, which is called leather belt in the Produce scene, is the continuous facility for transporting of the common enterprise of factories and mines. It is widely used under the well of coal mine, particularly extensively. The major parts of belt conveyer include conveyer belt, actuating device, bearing roller, cylinder, frame, tension station, brake, supplementary equipment as well as electromechanical protective device and so on. When designing belt conveyer, first, should determine original enumerated data, such as the expected productivity, conveyer transport line picture, the way of giving material and discharge way by working condition and the installation feature of conveyer as well as the physical mechanical performance of transportation stock and so on; And in the design cacula- tion of type selecting need to select related parameter reasonably, for example band- width, belt speed and wraps angle of the driving pulley, the operation resistance coefficient of parts , make them close to actual operation state worth in order to raise economic benefits and the comprehensive technology of belt conveyer. Since belt conveyer is to lean conveyer belt, the friction with drive pulley transmits haulage , therefore tension station can be designed with definite parameter according to the requirement for tension in the operation of conveyer belt which including characteristic, installation location, tension adjusting range and the type of tension station and so on. Tension station can directly affect the performance of belt conveyer as its performance of essential important composition part of belt conveyer. In belt conveyer system, the main effect of tension station has the following:（1）Guarantee conveyer belts split of driving pulley have proper tension in order to prevent conveyer belt from dozening slippery. Belt conveyer depend on the friction between support conveyer belt and driveing pulley, in appearance meet with split to produce a tension haulage of system. Therefore to make belt conveyer stabilize operation need to guarantee conveyer belt have enough tension in driveing pulley split place, in order to make conveyer belt rely on , with the friction of cylinder, transmiting the haulage needed by system. If split place has little tension, the friction haulage that conveyer belt transmits cant make belt conveyer run , conveyer belt would hit on cylinder slippery. (2) Guarantee having necessary tension each on the girth of conveyer belt so as satisfy sag requirement. Conveyer belts sag between two bearing rollers should not be exceptional , otherwise conveyer belt would relax excessly to lose groove shape cause the sideslip of conveyer belt , arouse spillage , increase operation resistance. Therefore automatic tension station should guarantee that conveyer belt has enough tension in the minimum tension place in order to restrict sag between bearing rollers on conveyer belt, keep belt conveyers steady operation. (3)The regulation of tension in the not steady working condition of start , brake etc. In the course of starting, because of acceleration sport of belt conveyer, the haulage that conveyer belt need to transmit bigger than steady operation much, therefore it has to raise the tension value in the split place of the driveing pulley to produce larger haulage. And in brake course, especially for the conveyer of long distance and big volume, as the role of force, the tension on the tight side of conveyer belt can reduce , even arouse the tape of layer upon layer probably; Loose side, the tension of conveyer belt can increase , even arouses belt broken probably , therefore tension value must be prompted in time. Additionally, in operation course, the change of load make leather belt appear suddenly tension unusual, tension station should be given prompt adjustment , in order to reduce leather belt to hit the accidents such as belt sliding, belt broken. (4) Compensate line viscous elongation and the flexible elongation of conveyer belt.conveyer belt can automatic elongation as time goniong, and occur permanent elongation under transitional operating mode, , so it is needed to compensate plasticity and the change of elongation in transitional operating mode. Since load change can arouse conveyer beltslength changing, vermicular phenomenon can also cause the elongation of conveyer belt, and tensile force changes , it has to regulate the location of tension pulley often , and guarantee the normal operation of belt conveyer. (5)Offer necessary route for conveyer belt to contact again.Each belt conveyer has some joints , possibility in certain contact for a short while can arise problem, must stop first and then make the joint again. Tension station has prepared the belt besides load for belt conveyer, so contacting fault can be contacted again through relax tension station to solve problem. For stretch out and draw back allowing belt conveyer, when storing up tape district to store up full tape, we can take out extra conveyer belt through tension station. Tension station, for belt conveyer transportation system, has the important role that cannot replace , therefore domestic and international scholar has carried out plenty of researches for it , has developed a lot of new products. Its development course can be sumed up approximately for 3 following stages:First stage is pure mechanical tension stage. The major product of this stage : Spiral tension station and stationary winch tension station and heavey hammer tension station. Heavey hammer tension station reaches the purpose that pulled through pulley groups and heavey hammer piece, , when the elongation of gummed belt, it can absorb its elongation voluntarily. The stationary winch tension stations function of tension is to pull only, when belt elongation tensile force drop because of various reason, it can be pulled again only it its discovered that is rear to pull . Since belt conveyer is different in starting and runing normally course for the tension requirement of conveyer belt,but the location of stationary winch tension station is tighted in conveyer operation course and all along to fix, to surmount this shortcoming,we can alter it for half stationary starts tightly , that is to say tension pulley fixed in starting location , when runing normally fixed in operation location , two locations uses route switch to control , domestic also can produce this kind of tension station. Second stage, the adjustable stage of tensile force. The typical product of this stage is voluntarily winch( mechanical winch or hydraulic winch) tension station. Its technology develop looked that it can only realize the automatic tight in steady( even speed) stage, it is constant to maintain the tension of gummed belt in steady stage. And its tensile force under the instability operating conditionses such as brake or starting-up is same as the stationary winch identical. Its structural feature shows: With floodgate, when winch is opened , loosens floodgate, when stoping tight floodgate. The time of winch operation is very short, and the most of times is in parking await orders state. Reduce the hydraulic of air tight system is to use compressed empty ware drive oil pump, offer tight oil cylinder with pressure oil to tight conveyer belt. That system only in the countries such as Germany and Engl get application, its structure is compact , has reliable work, it cover a little area.The stage of 3th, development automatic tight stage. Major product has hydraulic winch automatic tension station and hydraulic automatic tension station of big jar. Such as KJ2029 model which is domestic and international widely used belt conveyer esprcialy used in mines, the hydraulic automatic of big jar tight system used in A model belt conveyer produced in French, DYI hydraulic type of big jar tight system, these kinds of automatic tight system can accomplish the voluntarily regulation tensile force of conveyer belt , development is responded quickly , can offer corresponding tensile force under starting stage and normal operation stage two operating modes. Hydraulic winch is in working form hero for a long time, its structural feature is have no floodgate. Automatic tension station pulls conveyer belt with the tension station of pulling force, automatic tension station can not only come from according to the haulage of active cylinder to move regulation tensile force , and can also compensate plasticity and the flexible elongation of conveyer belt to warp, at the same time, allocate tension sensor and change to send ware, to survey the tension of conveyer belt. When the tension of conveyer belt occurs change , exceeds the scope of conveyer normal operation, the quick movement of tension station adjust the tension of conveyer belt , guarantee the normal operation of conveyer. Automatic tension station combines with moving tail coordination to use, it can realize conveyers tail move with conveyer belt stretch out and draw back in conveyer while do not need to stop machine ,which has raised the working efficiency of belt conveyer greatly. Now, the domestic and international various does not have the unify view for the applicability of tension stations yet, this shows that some conclusions which determines the nature still not perfect ,it is must to have ration conclusion to guide design. Refering to actual use condition, winch tension station and hydraulic tension station can realize automatic control and tensile force is adjustable , heavey hammer tension station has higher reliability. Along with the development of industry and technology, the large scale belt conveyer that has long distance, big volume and the high feature of belt speed has become the main stream of development, so as tension station puts forward , is higher to ask. Traditional tension station shows its shortcoming gradually, technical people will already change over to automatic tight field step by step as tighting systematic research direction . Such as the YZL series hydraulic winch type automatic tension station developed by the China university of mining industry mining industry. It can not only offers corresponding belt tension according to the different requirements of accelerating stage and smoothly operation stage for the tension of leather belt according to belt conveyer , but aslo accurate inspection and in time automatic adjustmentin when the tension of leather belt changed . Automatic tension station can raise the reliability of belt conveyer operation greatly. Early in last century in 40 decade, automatic tension station already comes out abroad, the Soviet is earlier to start with Japan in this field about type selecting of tension station. But the history of tightly systematic used in home is not quite long , theoretical research and design method about tension station till not perfect , it is slow to have tensile force comparing with abroad to respond , layout not reasonable , existence the insufficient places such as vibration phenomenon, for voluntarily calculation method, is also vague , is not as basic as ample theory. As belt conveyer develops to the direction of long distance, big volume and high belt speed, tension station should be able to realize that the tensile force can be measured adjustable and can be controled when woring , and should rise respond speed and respond precision, raise stroke of tension.For the belt conveyer of not large inclination, mostly uses vehicle type pulls which include: pushcart,cylinder ,tension generated equipment and the control system,tension generated equipment include: heavy hammer, Winch, hydraulic oil cylinder and so on.The way of the regulation tension of tension station of leather belt can be the tension value of constant maintenance; Or maintain the two constant tension values of leather belt ( start tension value and operation tension value ); Or maintain constant tension Proportion . In belt conveyer is systematic to arrange , reasonable definite tension station is to guarantee conveyer normal operation , start and brake safety and reliable as well as the necessity with reasonable economy prerequisite. The working property of tension station not only depend on its structural performance,but aslo concern with belt conveyers start ,brake property, the installation location of tension station. Thus to get the working property of accurate analysis tension station ,we must combine it with overallbelt conveyer,but not analyse tension station isolatedly. But when the belt conveyers structural , way of start-up,brake and tension installation location is definited, the property of tension station depends on its self performance.Tension station can be divided into stationary, heavy hammer type and automatic type 3 kinds according to structural type.(1) stationary tension station include spiral pull and regular winch pull.It is put up that pulls the bearings of pulls cylinder in spiral system to install when move about, moving frame can slide on rail, when revolving screw rod, it is together ongoing to make the nut on moving frame follow moving frame with retreat , reach the purpose that pulls and relaxes. Its characteristic is structure simple, but stroke of tension is too little , applies to the conveyer of short distance only, when general captain is smaller than 80 metres, just chooses. The shortcoming of spiral tension station is: After conveyer belt is used a not long time, as a result of plasticity is deformed, elongation, if havnt prompt adjustment, the tensile force of conveyer belt would reduce , conveyer belt can change loose and arouses conveyer belt to hit, is slippery. Additionally, because of load often change , conveyer belt receives load impact, the regular bolt that causes tension pulley is loose , screw rod retreats , from this cause the pine of conveyer belt Chi cause conveyer belt dozen slippery. Can not tight with the method of tightening screw rod after still having the screw rod that gets rusty , after causing the elongation of conveyer belt.Regular winch tension is to pull using small-sized winch. Winch use worm and worm gear reducer normally to drive reel twine wire rope, in order to pull belt. The advantage of this kind of tension station is: Volume is little , pulling force big, so have been applied extensively on belt conveyer under the well of coal mine. Its shortcoming is: It can only regulate according to needs, after regulating , produce regular tensile force. When winch arises problem with control system, for belt conveyer, can not produce constant tensile force or tensile force to become invalid, safe and reliability reduces relatively.Fix winch tight way that can only adjust conveyer belt tight level regularly.Normally, beginning has been in to tight state , makes the conveyer belt bear extra additional load, and in operation course, tensile force Gradually reduces along with permanently change of conveyer belt to increase,and regular appearance gradually to hit slippery phenomenon. Additionally, use regular winch as the tension station of the belt conveyer of long distance, conveyer belts moveing stress is big for the conveyer belt of certain strength, its safe and reliability will drop , arises broken tape accident easily. Once belt breaking accident occur, conveyer belt need to be joined again, and the falled down coal need to be cleaned, it usually need to stop production for 24 hours even more long time. Besides break to take accident occur would still cause the casualty accidents of pedestrian on the side of belt conveyer.(2) type of heavey hammer tight.Heavy hammer tension equipment ,including one hammer type, multiple hammers type and hammer vehicle type. The structure of heavy hammer tension equipment is simple , it is applied comparatively extensively, can guarantee tensile force maintenance constant in various operating conditionses, and can absorb and compensate the elongation of conveyer belt voluntarily. Heavy hammer tension equipment pulls conveyer belt through takeing affect wire rope tension pulley , Pull pushcart can level or incline to arrange, it can be also vertical to arrange. It acts using heavy hammer, to hang heavy hammer need to boil one special room. In belt conveyer system that pulling pushcart arranged on incline to pull belt,neednt to arrange heavy hammer but to put hammer on pushcart,so that pushcart can pull belt using its using slope force, it is also called heavy hammer vehicle tension equipment. The characteristic of heavy hammer tension equipment is that tensile force does not change , has higher reliability; Pull force do not change is also its shortcoming at the same time, as a result of tensile force can not regulate , at the stage of starts , as well as transport quantity occur change conveyer belt can hit since tension is below slippery, in starting and stabilizing not operation course, also produce vibration easily since tension is not suitable. Besides,since the arange room is restricted ,the displacement of hammer should not be too large.(3) automatic pull.Automatic tension equipment is the type of tension equipment of extensive application in modern conveyer, it make conveyer belt have reasonable tension distribution , and compensates the flexible deformed and plasticity elongation of conveyer belt voluntarily. Automatic tension equipment twines wire rope normally by winch to pull cylinder, so pull leather belt.Automatic tension equipment can be divided into electric winch tension equipment and hydraulic winch tension equipment according to different forms of driving; according to the change law of a little tension on split point which can be regulated , it can be divided into steady type , follow to move type and comprehensive type 3 kinds of type. Stabilize type automatic tension station can make split the tension of conveyer belt keep in the sphere of certain error constant, and do not rely on other parameter and adhesion condition as well as the change of belt conveyer load. To guarantee belt conveyer to start conveyer belt do not hit slippery, ask steady type automatic tension station to guarantee conveyer to start conveyer belt split tension reach steady operation deserve 1.4 1.8 times. Follow to move type automatic tension station can make conveyer belt appearance meet tension with split the ratio of tension maintenance is decided value.its role way is follow to move type, and when stabilizing operation, its role way is steady type Or it is opposite，that is the character of synthesize the characteristic of Synthesize type automatic tension station.The advantage of automatic winch tension station is known gradually extensively by people, but also exist a lot of shortcomings. Electric winch tension station is to use tension sensor in order to feedback , adjusts the size of tensile force voluntarily according to the different operating conditions of belt conveyer , has not high quality by tension sensor or mechanical systematic inertia and the influences such as signal hysteresis and automatic winch have misoperation phenomenon , affect it to use ; Hydraulic winch tension station is to regulate the size of tensile force by the pressure oil that hydraulic station produces through controling hydraulic winch , since hydraulic station and oil cylinder are in working state all along, when hydraulic systematic or control system arises fault, for conveyer belt, can not produce tensile force or tensile force to become invalid, reliability reduces relatively. Besides winch, hydraulic big jar can also be carry out element to pull, the hydraulic automatic tension station of big jar can also accomplish the voluntarily regulation tensile force of conveyer belt, satisfy conveyer belt in start as well as the t