往復(fù)式給煤機(jī)設(shè)計(jì)
往復(fù)式給煤機(jī)設(shè)計(jì),往復(fù),設(shè)計(jì)
Equipment of the coal mine production system is one of the main equipment, the reliability of it, in particular parts of the throat is the key to the reliability of such equipment, will directly affect the normal operation of production systems. At present, China's coal mines to the coal used primarily is reciprocating coal feeder and coal to power vibration machine, In recent years, the electric machine vibration to the development of coal faster serialization and standardization has been formed; and reciprocating coal feeder 60 from the 20th century's stereotypes, the series of improvement and expansion of the work has been carried out. With the rapid development of the coal industry, coal type is also growing well, the existing reciprocating coal feeder Coal is no longer able to meet the selection requirements of production systems. It is precisely for this reason that，We are on the basis of the coal feeder for the use of a large number of studies，development of the large-scale reciprocating coal feeder, include 800t / h, 1000t / h, 1500t / h, 2000t / h, Reciprocating the earliest development of coal feeder 60 in the early 20th century, 70 years, based on the NGW, the replacement of the drive into K series, and are still in use. Reciprocating coal feeder of K series has a total of five models: K-0, K-1, K-2, K-3, K-4, K-4 is the largest production capacity, but still only 590t / h. The development of Reciprocating coal feeder has no different between abroad and national, it doesn’t have a higher technological content, but the price is 4 to 5 times in similar products.
1、The own structure superiority of reciprocating coal feeder
1) Structure simple, the service quantity is small .In the reciprocating coal feeder, the electric motor and Reduce use the standard letter, other majorities are the Welding parts, the vulnerable part are few, Under bad conditions in the coal mine, its serviceability deeply Praised by the use of units.
2) The performance is stable The reciprocation type stoker to the coal trademark, the size composition, request and so on moisture content, physical property is lax, when comes to expect the non-uniformity, the moisture content does not stabilize also clamps has the big lump coal, Rubber Belt, the wood and the steel wire, and so on ,still could the normal work.
3) The noise is low the reciprocation type stoker right and wrong Vibration has the source for material equipment. its noise only to have the electric motor and the reduction gear, but these two noises very are all low .Especially in the mine shaft or Bunker and so on the enclosed place，the noise is unable to proliferate, this point is electrically operated is unable for the material machine to achieve.
4) Installs conveniently, is highly small The reciprocation type stoker generally installs in Bunker the warehouse mouth, does not need other configuration warehouse mouth strobe distill trough and the support of motor, the installment may reach one's goal instantly, the adjustment work load is small, but electrically operated stoker because cannot directly withstand the warehouse pressure, needs moreover to place the warehouse mouth transition Chute under, compares, the reciprocation type stoker hold highly slightly, has saved the floor space and the investment.
2、Large-scale reciprocation types deceive the coal machine structural style characteristic .
We through carry on the analysis to the former stoker investigation, has carried on the thorough computation to the structure pattern, to the essential stress spot like tank, the double connecting rod, the base held the roller and so on to carry on the stress analysis, carried on the examination computation using the finite element principle. Altogether has following five characteristics.
1) Entire machine uses the frame Themselves to be possible to unload the type Because considered the mine shaft transportation the convenience and the mine shaft industry and mining limit, entire machine uses a minute writing style, moreover considered the mineshaft welding inconvenient, uses the bolt vice- joint, the side bar to consider the external drum the possibility and the wear the need, lays down in the flank Reinforced inside Lining, strengthened the whole rigidity and the intensity.
2) Increases Dao ban the guidance and the blocking In makes the reciprocal motion under Dao ban to additionally build several groups of requests rollers wheel, on the one hand changes Dao ban the sliding friction for to roll the friction, reduced the attrition, on the other hand also causes Dao ban the rigidity enhancement. Moreover, for prevented Dao ban is transporting Moves in the process to have runs the leaning phenomenon, in Dao ban two sides installments guidance wheel.
3) Uses the hyperbolic trough drive type The stoker drive uses the hard tooth face reduction gear，ordinary plug shaft coupling (but non- fluid strength coupler), double output shaft form, like this, not only reduced the cost moreover to cause the unilateral Axis radial direction load only is the bottom surface thrust force one half, is carried the condition big improvement, moreover, further enhanced the stability which Dao ban moved.
4)Carries on the optimization to the Dao ban structure Formerly K series stoker plate strobe, the material had many problems in shipping, for estimated could not enhance the key also lay in this. Therefore, we have carried on the optimization to Dao ban designs for the steps and ladders, Not only caused the material process load to enlarge, more over the Dao ban itself intensity also obtained further enhances.
5) Changes the fan strobe for the manual plate strobe Controls expects how many the key to be decided by the strobe，the strobe always uses the fan structure in the former K series, but discovered from the field use, the fan strobe and the warehouse wall frequently bump, the scene often when installs the strobe can not but knock the warehouse wall a part, causes the warehouse wall the intensity to weaken, based on, we uses the manual plate strobe，matches the guidance wheel under the damper plate, simultaneously has the positioning device on the axis.
3. Reciprocating the transformation of coal feeder
3.1 、The transformation of Link
（1）Transformation of the former coal feeder K4 transmission parts .As shown in Figure 1, The drive for: The Reducer driven by a motor ,and Crank driven by the reducer, Qu Shui driven the floor of reciprocating coal feeder do a straight line reciprocating motion.
1、Motor 2、Reducer 3、Crank 4、Bearing 5、Qu Shui
Fig·1 Transformation of the former coal feeder transmission parts diagram
As a result of the use of coal , it more easily fit into the bearing impurities, the poor maintenance will damage bearings, the damaged bearings would be detect serious mechanical, electrical accident if failed to timely detection,either Qu Shui is to pull off or motor is burning. If shortage of the motor and spare parts and components, it will occur on a longer time, so transformation is necessary （for this transformation）.
（2） Transmission parts of K4 reciprocating coal feeder after improved
Transmission principle has not changed, Figure 2, Changed the eccentric into crank, The circumference of the eccentric into a tank at the top of open, Linked with a good off-type tungsten deposit matching tile sets, tile sets and through the connecting shaft connected to the coal feeder floor, Is actually an eccentric crank into the sliding bearings, When the motor drive reducer and eccentric wheel rotation, the eccentric wheel with the tile sets with connections on the drive shaft to the coal feeder and do a straight line reciprocating motion plate, reaching to the purpose of coal.
1、motor 2、Reducer 3、Eccentric 4、Sets of gold-watt tungsten
5、Connecting shaft 6、Oil Cup
Fig·2 Modified coal feeder transmission parts diagram
3.2 Structural Analysis and Improvement
(1) Improve disk
K series reciprocating coal feeder plate stroke adjustment is achieved through the disc, Structural diagram of its components as shown in Figure 3, According to long-term use found that the parts have the following shortcomings: ① D hole and journals connected with the use of the transition, the actual connection is not reliable in use, the journal often off; ②the pins connected with hole O1 often break, it can not guarantee that the needs of the trip back and forth movement. In view of the above shortcomings, we improved the disc as follows in actual use: ① D-hole match with the journal use space , and to expand the Chamfer of D hole, welding the disk with the journal. In this way, not only increase the reliability of the connection, but also facilitate the replacement of damaged parts. According to crank structure, in diameter position with o1, additional o2, o3, o4 3 months Hole, As shown in Figure 2. after location the hole and 5, when the hole o1 and 1, o1 and 2, o1 and 3, o1 and 4 through the fastening pin, the respective o4 and 4, o3 and 4, o2 and 4, o4 center coincide with the 1 . Thus the connection about Crank with the disc can be achieved three pin fastening, an increase of the reliability of connection.
Fig·3 Diagram of disk
(2) Improvement of the disc crank
By the above analysis, if the crank in Figure 4 into a 60 ° hole 1,2,3,4 are cloth, the holes in the disk o1, o2, o3, o4 also as 60 ° are cloth, can be multi-pin fastening (analysis omitted). Another way is change crank disk body into a flange-type connection, as shown in Figure 5. O with the crank journal hole distance o1 is eccentricity, eccentricity is calculated as
R2=R21+R22-2R1R2icos360/n
Formula in R———Eccentricity, That is, half the trip back and forth
R1———Crank eccentricity
R2———Journal of the hole disk eccentricity
n———The number of bolt holes
The range of i from 1,2, ..., n, In this way, can be flange-type crank drive mechanism of the series size, travel back and forth in a certain range can be selected arbitrarily.
Fig·4 Diagram of crank and disk
1 ~ 5·Hole 6·Crank 7·Disc
Fig·5 Crank and disk mechanism after improved
(3) Improvement of gate fan-shaped
K series fan gate of the coal feeder is adjustment inconvenience, high failure rate, after card in prison by the debris was not easy to restore, we will change the flat fan-shaped gate into flatboard gate in the actual use. Welding angle iron on the side board, as a channel with the flat gate, their number can be change in order to achieve adjustment to the amount of coal, then achieve the purpose of removal of large pieces of debris.
(4) Anti-wear lining side increase
K Series medial side to the coal machine wear, and replacement costs and time-consuming work, and to the security threats brought about by the construction personnel. We increase Anti-wear to improve the life of the reciprocating coal feeder, the connection of lining and side panels use welding, in addition to peripheral welding, the intermediate slotted plug with the solder side.
4、 Power consumption analysis and energy-saving measures of Reciprocating coal feeder
Power consumption analysis and energy-saving measures of Reciprocating coal feeder used ultra High Molecular Weight Polyethylene material for lining, Friction coefficient of coal and fixed side decreased, the running resistance decreased 7%, corresponding, 7% reduction in power consumption motor.
It is limited to reduce the friction coefficient of Bottom of reciprocating coal feeder and coal, this is because when Masayuki, coal in the feeder chute body of reciprocating coal feeder is between the friction in its dealings and the floor under the front-end , then move to the coal feeder. The friction of Bottom of reciprocating coal feeder and coal is greater than the dynamic resistance when coal accelerated and the Friction of side board friction, in order to ensure that coal and bottom line is no relative sliding when moving forward. Therefore, the friction coefficient of coal and floor should not be between the lower coefficient of friction. I funnel tilted position using the modified reciprocating coal feeder, coal bunker to avoid the exit of the pressure acting on the activities of floor, floor to reduce the activities of running resistance, reciprocating coal feeder is an effective energy-saving measures. I used chute tilt position, I need to increase the coal bunker to the high floor space, increasing the volume of civil works. However, to increase coal bunker limited height (K-4 type reciprocating coal feeder to improve 0.6m), and significantly reduce operating costs, an integrated energy-saving benefits are obvious. Fixed side of coal and reduce the friction coefficient, but also a certain degree of energy saving effect. Coal between the floor and activities should not reduce the coefficient of friction.
Develops the large-scale reciprocation type stoker, met our country coal need to develop, Expanded in the coal mine production system design to give the coal equipment the shaping scope. In particular in Ji Ning two mine pits success uses, for me The country provided has been new large-scale for the coal equipment, should give the vigorously promoted use. The transformation and Apply of reciprocating coal feeder played a role in the Development of reciprocating coal feeder.
給煤設(shè)備是煤礦生產(chǎn)系統(tǒng)的主要設(shè)備之一,給煤設(shè)備的可靠性,特別是關(guān)鍵咽喉部位給煤設(shè)備的可靠性,直接影響整個(gè)生產(chǎn)系統(tǒng)的正常運(yùn)行。目前,我國(guó)煤礦使用的給煤設(shè)備主要是往復(fù)式給煤機(jī)和電振給煤機(jī),近年來(lái),電振式給煤機(jī)發(fā)展較快,已形成系列化和標(biāo)準(zhǔn)化;而往復(fù)式給煤機(jī)自20世紀(jì)60年代定型后,系列的改進(jìn)和擴(kuò)大工作一直沒(méi)有進(jìn)行。隨著煤炭工業(yè)的迅猛發(fā)展,煤礦井型也在不斷擴(kuò)大,現(xiàn)有的往復(fù)式給煤機(jī)已不再能滿足煤礦生產(chǎn)系統(tǒng)的選型要求。正是基于這個(gè)原因,我們?cè)趯?duì)給煤機(jī)使用情況大量調(diào)研的基礎(chǔ)上,研制了800t/h、1000t/h、1500t/h、2000t/h的大型往復(fù)式給煤機(jī),往復(fù)式給煤機(jī)最早研制于20世紀(jì)60年代初,70年代,在NGW基礎(chǔ)上,更換了驅(qū)動(dòng)裝置,改為K系列,并一直沿用至今。K系列給煤機(jī)共有五種型號(hào):K-0、K-1、K-2、K-3、K-4,其中K-4生產(chǎn)能力最大,但也只有590t/h。國(guó)外給煤機(jī)發(fā)展?fàn)顩r也與國(guó)內(nèi)大相徑庭,并沒(méi)有更高的技術(shù)含量,但價(jià)格卻是國(guó)內(nèi)同類產(chǎn)品的4-5倍。
1、往復(fù)式給煤機(jī)其自身結(jié)構(gòu)的優(yōu)越性
1) 結(jié)構(gòu)簡(jiǎn)單，維修量小
在往復(fù)式給煤機(jī)中，電動(dòng)機(jī)和減速器均采用標(biāo)準(zhǔn)件，其余大部分是焊接件，易損壞部件少，用在煤礦惡劣條件下，其適用性深受使用單位的好評(píng)。
2) 性能穩(wěn)定
往復(fù)式給煤機(jī)對(duì)煤的牌號(hào)，粒度組成，水分、物理性質(zhì)等要求不嚴(yán)，當(dāng)來(lái)料不均勻，水分不穩(wěn)定且?jiàn)A有大塊煤、橡膠帶、木頭及鋼絲等時(shí)，仍能正常工作。
3) 噪音低
往復(fù)式給煤機(jī)是非振動(dòng)式給料設(shè)備．其噪音發(fā)生源只有電動(dòng)機(jī)和減速器，而這兩個(gè)的噪音都很低。尤其在井下或煤倉(cāng)等封閉型場(chǎng)所，噪音無(wú)法擴(kuò)散，這一點(diǎn)是電動(dòng)給料機(jī)所無(wú)法達(dá)到的。
4) 安裝方便、高度小
往復(fù)式給煤機(jī)一般安裝在煤倉(cāng)倉(cāng)口，不需另外配制倉(cāng)口閘門餾槽及電動(dòng)機(jī)支座，安裝可一步到位，調(diào)整工作量小，而電動(dòng)給煤機(jī)由于不能直接承受倉(cāng)壓，需要另外安放倉(cāng)口過(guò)渡溜槽，相比之下，往復(fù)式給煤機(jī)占有高度小，節(jié)省了建筑面積和投資。
2、大型往復(fù)式紿煤機(jī)的結(jié)構(gòu)形式特點(diǎn)
我們通過(guò)對(duì)以往給煤機(jī)的調(diào)查進(jìn)行分析，對(duì)結(jié)構(gòu)型式進(jìn)行了周密的計(jì)算，對(duì)關(guān)鍵受力部位如槽箱、雙連桿、底部托輥等進(jìn)行了受力分析，利用有限元原理進(jìn)行校核計(jì)算。共有以下五個(gè)特點(diǎn)。
1)整機(jī)采用框袈可卸式
由于考慮到井下運(yùn)輸?shù)姆奖愫途鹿さV的限制，整機(jī)采用分體式，而且考慮到井下焊接的不便，盡 用螺栓副聯(lián)接，側(cè)板考慮到外鼓的可能與內(nèi)壁磨損的需要，在外側(cè)加筋內(nèi)側(cè)鋪設(shè)襯板，加強(qiáng)了整體的剛度和強(qiáng)度。
2) 增加導(dǎo)板的導(dǎo)向與支撐裝置
在做往復(fù)運(yùn)動(dòng)的導(dǎo)板下增設(shè)幾組托輥輪，一方面變導(dǎo)板的滑動(dòng)摩擦為滾動(dòng)磨擦，減少了磨損，另一方面也使導(dǎo)板的剛度提高。另外，為防止導(dǎo)板在運(yùn)動(dòng)過(guò)程中有跑偏現(xiàn)象，在導(dǎo)板兩側(cè)安裝導(dǎo)向輪。
3) 對(duì)導(dǎo)板結(jié)構(gòu)進(jìn)行優(yōu)化
以往K系列給煤機(jī)的平板閘門，物料在運(yùn)送中存在不少問(wèn)題，給料量一直不能提高的關(guān)鍵也在于此。為此，我們對(duì)導(dǎo)板進(jìn)行了優(yōu)化，設(shè)計(jì)為階梯型，不但使物料處理量加大了，而且導(dǎo)板本身的強(qiáng)度也得到進(jìn)一步地提高。
4) 變扇型閘門為手動(dòng)平板閘門
控制來(lái)料多少的關(guān)鍵取決于閘門，閘門在以往的K系列中一直采用扇型結(jié)構(gòu)，但從現(xiàn)場(chǎng)使用中發(fā)現(xiàn)，扇型閘門與倉(cāng)壁經(jīng)常相碰，現(xiàn)場(chǎng)往往在安裝閘門時(shí)不得不把倉(cāng)壁敲去一部分，使倉(cāng)壁的強(qiáng)度削弱，基于次，我們采用手動(dòng)平板閘門，在閘板下配導(dǎo)向輪，同時(shí)在軸上配有定位裝置。
3往復(fù)式給煤機(jī)的改造
3.1 連桿的改造
1)改造前K4給煤機(jī)傳動(dòng)部分如圖1所示,該傳動(dòng)方式為:由電動(dòng)機(jī)帶動(dòng)減速機(jī)再帶動(dòng)曲柄、曲拐使給煤機(jī)底板作往復(fù)直線運(yùn)動(dòng)。
1、電動(dòng)機(jī) 2、減速器 3、曲柄 4、軸承 5、曲拐
圖1 改造前給煤機(jī)傳動(dòng)部分簡(jiǎn)圖
由于使用環(huán)境煤粉多,軸承內(nèi)極易進(jìn)入雜質(zhì),維護(hù)不好會(huì)使軸承損壞,軸承損壞后不及時(shí)發(fā)現(xiàn)就會(huì)發(fā)生嚴(yán)重的機(jī)械、電氣事故,不是將曲拐拉斷就是將電機(jī)燒毀。如果電機(jī)及零部件備用不足,發(fā)生事故影響時(shí)間較長(zhǎng),為此改造非常必要。
2)改造后K4給煤機(jī)傳動(dòng)部分如圖2, ,傳動(dòng)原理沒(méi)有變,只是將曲柄改成偏心輪,把偏心輪的圓周頂部開成油槽,與一個(gè)對(duì)開式掛好鎢金的瓦套相配合,瓦套通過(guò)連接軸與給煤機(jī)底板相連,實(shí)際上就是將曲柄改成了一個(gè)偏心的滑動(dòng)軸承,當(dāng)電機(jī)帶動(dòng)減速機(jī)及偏心輪轉(zhuǎn)動(dòng)時(shí),同偏心輪配合的瓦套就帶動(dòng)連接軸與給煤機(jī)底板做直線往復(fù)運(yùn)動(dòng),達(dá)到給煤的目的。
1、電動(dòng)機(jī) 2、減速器 3、偏心輪4、鎢金瓦套5、連接軸6、注油杯
圖2 改造后給煤機(jī)傳動(dòng)部分簡(jiǎn)圖
3.2 結(jié)構(gòu)分析與改進(jìn)
(1)圓盤改進(jìn)
K系列給煤機(jī)往復(fù)板的行程調(diào)節(jié)主要是通過(guò)圓盤來(lái)實(shí)現(xiàn)的,其零件結(jié)構(gòu)簡(jiǎn)圖如圖3所示,根據(jù)長(zhǎng)期使用發(fā)現(xiàn)該零件有如下缺點(diǎn):①D孔與軸頸采用過(guò)渡配合連接,實(shí)際使用中連接不牢靠,軸頸經(jīng)常脫離;②與孔o(hù)1聯(lián)接的定位銷經(jīng)常折斷,不能保證往復(fù)運(yùn)動(dòng)需要的行程。針對(duì)以上缺點(diǎn),我們?cè)趯?shí)際使用中對(duì)圓盤進(jìn)行了如下改進(jìn):①D孔與軸頸改用間隙配合,并擴(kuò)大D孔的倒角、將圓盤與軸頸焊接。這樣,既增加了聯(lián)接的可靠性,又便于零件損壞時(shí)更換。②根據(jù)曲柄結(jié)構(gòu),在與o1 等徑位置處增加o2、o3、o4 3個(gè)孔,如圖4所示。在孔o(hù)5與5定位后,當(dāng)孔o(hù)1與1、o1與2、o1與3、o1與4通過(guò)銷緊固時(shí),分別有o4與4、o3與4、o2與4、o4與1圓心重合。因而曲柄與圓盤的聯(lián)接可實(shí)現(xiàn)三銷緊固,增加了聯(lián)接的可靠性。
圖3 圓盤簡(jiǎn)圖
(2)曲柄圓盤的改進(jìn)
按上述分析,若將圖2曲柄中孔1、2、3、4成60°均布,圓盤中的孔o(hù)1、o2、o3、o4也成60°均布,則可實(shí)現(xiàn)多銷緊固(分析略)。另一種方式是將曲柄圓盤機(jī)構(gòu)改為法蘭式聯(lián)接,如圖5所示。軸頸孔o(hù)與曲柄o1的距離即為偏心距,偏心距計(jì)算公式為：
R2=R21+R22-2R1R2icos360/n
式中R———偏心距,即往復(fù)行程的一半T
R1———曲柄偏心距
R2———圓盤的軸頸孔偏心距
n———螺栓孔數(shù)量
i 的取值范圍為1,2,…,n,這樣,可得到法蘭式曲柄傳動(dòng)機(jī)構(gòu)的系列化尺寸,復(fù)行程在一定范圍內(nèi)可任意選定。
圖4 曲柄及圓盤簡(jiǎn)圖
1 ~ 5·孔 6·曲柄 7·圓盤
圖5 改進(jìn)后的曲柄圓盤機(jī)構(gòu)
(3)扇形閘門的改進(jìn)
K系列給煤機(jī)扇形閘門調(diào)節(jié)不便,損壞率高,被雜物卡牢后不易恢復(fù),我們?cè)趯?shí)際使用中將扇形閘門改成了平板閘門。在側(cè)板上焊角鋼,用槽鋼作為平板閘門,其數(shù)量可根據(jù)需要增減,從而實(shí)現(xiàn)調(diào)節(jié)給煤量,清除大塊雜物的目的。
(4)側(cè)板增加抗磨襯板
K系列給煤機(jī)側(cè)板內(nèi)側(cè)磨損量大,更換費(fèi)工費(fèi)時(shí),且給施工人員帶來(lái)安全威脅。我們通過(guò)對(duì)側(cè)板加抗磨襯板來(lái)提高給煤機(jī)壽命,襯板與側(cè)板的聯(lián)接采用焊接,除周邊焊接外,中間開縫與側(cè)板塞焊。
4、往復(fù)式給煤機(jī)的能耗分析與節(jié)能措施
往復(fù)式給煤機(jī)的能耗分析與節(jié)能措施采用超高分子量聚乙烯材料作襯板,煤與固定側(cè)板的摩擦系數(shù)下降了,運(yùn)行阻力減少7% A,相應(yīng)地電動(dòng)機(jī)功耗減少7%。
減少煤與底板的摩擦系數(shù)是有限的,這是因?yàn)檎袝r(shí),給煤機(jī)槽體內(nèi)的煤是在其與底板之間的摩擦力作用下移到給煤機(jī)前端。煤與底板的摩擦力要大于煤在加速時(shí)的動(dòng)阻力和煤與固定側(cè)板的摩擦力,才能保證在正行時(shí)煤與底板間不產(chǎn)生相對(duì)滑動(dòng)。因此,煤與底板間的摩擦系數(shù)不宜降低。采用傾斜倉(cāng)口漏斗的改進(jìn)型往復(fù)式給煤機(jī),可避免煤倉(cāng)出口處壓力作用于活動(dòng)底板,減少活動(dòng)底板運(yùn)行阻力,是往復(fù)式給煤機(jī)有效的節(jié)能措施。采用傾斜倉(cāng)口溜槽,需要提高煤倉(cāng)口至地坪的空間高度,增加土建工程量。但煤倉(cāng)口高度提高有限(K-4型往復(fù)式給煤機(jī)提高0.6m),而運(yùn)營(yíng)費(fèi)用大大降低,綜合節(jié)能效益是明顯的。降低煤與固定側(cè)板的摩擦系數(shù),也有一定的節(jié)能效果。煤與活動(dòng)底板間的摩擦系數(shù)不宜降低。
研制大型往復(fù)式給煤機(jī)，適應(yīng)了我國(guó)煤炭發(fā)展的需要，擴(kuò)大了煤礦生產(chǎn)系統(tǒng)設(shè)計(jì)中給煤設(shè)備的選型范圍。尤其是在濟(jì)寧二號(hào)礦井的成功使用，為我國(guó)提供了新的大型給煤設(shè)備，應(yīng)予大力推廣使用。往復(fù)式給煤機(jī)的改造以及應(yīng)用對(duì)給煤機(jī)的發(fā)展起到了一定的作用。
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