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1、<p><b>  外文原文:</b></p><p>  The vertical Boom-type Roadheader design</p><p>  1 Introduction</p><p>  Mechanical design is in the process of product design and an i

2、mportant part of the main links, it is followed in programme design after the design work. The vertical Boom-type roadheader (the roadheader) to the overall design of the merits of complete machine play a decisive role,

3、and the decision of the assembly, the system, coordination between the various components of the unity and match, to obtain the high-end performance and overall better economic efficiency technology. Roadheader design,&l

4、t;/p><p>  2 the selected models and various components and structural type, drive, and the overall layout of the reasonable</p><p>  In determining the content, first task should be designed to me

5、et the contents, especially the users of the main demands of the investigation, the two sides exchanged views repeatedly, to satisfy both users (or superior) conditions, can better meet the product development of the ove

6、rall plan.</p><p>  2.1 the selected models</p><p>  According to roadheader use, for the coal mine tunnel boring or used for other sectors of the works, roadheader working conditions for cuttin

7、g coal roadway or semi-Coal Lane, the compressive strength of coal and rock one-way (or the value of platts coefficient f) and the rock abrasion factor. At the same time the control line should be superscript MT138 ~ 199

8、5 "cantilevered Roadheader types and parameters",</p><p>  according to cutting coal and rock the biggest one-way compressive strength, the type of selected models.</p><p>  2.2 the st

9、ructure of the various components, the way the driver identified</p><p>  Roadheader by cutting general agencies, shipping agencies, walking, hydraulic system, electronic control systems and auxiliary device

10、s (such as dust removal devices, security devices, remote monitoring devices) and other components. 1) Cutting agencies. Cutting the drive from AC motor-driven, in the transmission system located in the general profile c

11、oupling with no mechanical overload protection device, the two planets reducer driven spindle front of the cutting head. Some sections of the worki</p><p>  factor, loading good effect, the application is wi

12、despread. However, such institutions loading width restricted (because boring machine running track when agencies generally do not arouse). To expand the loading width, will shovel the entire harrow board, together with

13、the claw agencies in the level of swing, or design dual rake claws, to expand the scope of loading. Institutions than the rake-wheel-claw simple, high intensity, reliable, but with less bulk materials. Loading agency pro

14、gramme is </p><p>  and wear more serious. At present cross-section of the boring machine is usually used crawler-run institutions. Walking agencies tracked the general pattern, the two tracked separately by

15、 the respective power to drive, to achieve in situ. Caterpillar is the driving force of two motors and hydraulic motors, motor driver is generally set up a walking speed, hydraulic motor-driven large low-speed torque mot

16、or can be driven directly tracked sprocket, or used in the hydraulic motor speed Reducer led </p><p>  2.3 Layout</p><p>  General layout of the contents include the following: 1) Identify the c

17、omponents in complete machine said the location, shape and size of the request; 2) To identify the parts, components and the connections between complete machine; 3) estimates complete machine weight and the weight of al

18、l components requested; 4) layout of the manipulation of institutions, the driver's seat;</p><p>  5) examination of moving parts of the movement space, rule out the possibility of interference in the ca

19、mpaign.</p><p>  2.4 specific requirements</p><p>  Boring machine in the general layout, the need to pay attention to the following questions: 1) institutions into the reducer reducer, as far a

20、s possible to coax axis; 2) cantilever and spade-suited to the size of relations, not only conducive to loading, to avoid cutting the first shovel cutting board; 3) the level of cantilever and vertical position can swing

21、 the center coincidence, can not overlap. From the increased stability of the machine, these are highly swing should be reduced. In the ca</p><p>  2.5 types and power transmission components choice</p>

22、;<p>  transmission patterns and components should follow the principle of choice 1) the advanced nature of technology: machines to improve performance, increase productivity; 2) economic rationality: drive system

23、 as simple as possible, fewer components and easy processing, low price, easy maintenance, long life;</p><p>  3) reliability of the work: the transmission system reliability performance for the life of comp

24、onents, as well as component quality requirements; 4) adaptation: the drive system components should be adapted to load, working conditions and environmental conditions of the request. Agencies to the transmission system

25、 requirements and the choice of transmission patterns . Boring machine cutting, loading, transport, walking and other institutions generally are respectively transmission, all parts of</p><p>  3) walk the t

26、rack-driven approach and a motor-driven motor oil in two ways. Respectively, through mechanical devices or directly from the slowdown in motor oil led the initiative sprocket running track. Mechanical transmission of the

27、 walking track, with General Motors will be tracked in two reducer rear, the brake hydraulic braking by mechanical means way. This transmission mode drive high reliability and low prices of motor, easy maintenance, but n

28、ot speed, slow me larger, Lin Shui major roadwa</p><p>  3 determination complete machine main technology senate parameter</p><p>  Mechanical Roadheader complete machine main technical paramete

29、r including size senate parameter (length ×width ×highly); weight parameter, parameter of movement and dynamic parameter.</p><p>  3.1 size parameters</p><p>  Complete machine length,

30、 width of the size directly related to its turning radius, Recommended light-length ≤ 7.5 m, medium-length ≤ 8.5 m, heavy machine ≤ l0m, the corresponding width were ≤ 1.6 m, ≤ 2.5 m, ≤ 3 m. The complete machine relates

31、its tendency, the static stability highly directly, the adaptation scope and passes quality, therefore lower better. The current development trend of Chinese and foreign models is the dwarf models, medium and heavy-high

32、1.6 ~ 2 m, special light, light mach</p><p>  3.2 weight parameters</p><p>  The complete machine dead weight is the mechanical roadheader - an important parameter, the engine weight too is ligh

33、t, the work stability drops, when swinging cutting can occur fishtails the phenomenon, the cutting efficiency drops, truncation tooth rate of wear increase; Heavy-weight, poor mobility, flexibility to decline. The self-r

34、espect as it may be w = (t) estimates, in the N-type body for cutting power, kW; V for the cutting head on average cutting speed, m / s; can also be Roadheader wit</p><p>  ≤ 0.14 MPa; muddy for the water to

35、 soften the shale bottom, </p><p>  ≤ 0.05 MPa.</p><p>  3.3 movement parameters</p><p>  Cutting the movement parameters: cutting head of the average cutting speed V: on the one-wa

36、y coal and rock compressive strength of σ c ≤ 40 MPa, V = 3 ~ 3.5m / s;</p><p>  σ c ≤ 60MPa, V = 2 ~ 2.5m / s, σ c > 60MPa. V = l ~ 2m / s. But eventually cutting</p><p>  speed by cutting t

37、echnology to determine.</p><p>  3.4 dynamic parameters</p><p>  Roadheader-driven power sources are used Motors. Cutting power body size. In fact the general use of analogy, combined with roadh

38、eader some personality and</p><p>  experience factors to determine. Roadheader in the operating process, the vertical axis and the horizontal axis-of the need for adequate cutting edge and push forward swin

39、g (horizontal and vertical) force. According to Russia (the former Soviet Union) in the laboratory test results that the cutting of coal and rock platts hardness f = 4 ~ 6 (equivalent to 0 C = 40 ~ 60MPa), grinding coeff

40、icient F = 5 ~ 7mg/mm2. Cutting the shaking force (traction) Pv = (1 ~ 1.34) P, P = M / Rcp, in the P-cutting</p><p>  3.5 technical and economic indicators</p><p>  Q = (m3/min), in the sx-cutt

41、ing head for the verticalcross sectional area, m2: Vn for the cutting head of cutting swing speed, m / min. Roadheader designed life, in the international advanced products up to 3 to 5 years, during which the need of ma

42、jor repair or wells, the general domestic product for 1 to 2 years.</p><p>  4 in accordance with design requirements. Determine the parameters of the main components and their relationship between the conne

43、ctor</p><p>  4.1 cutting agencies and technical parameters of the established link between</p><p>  1) Cutting-agency technical parameters of cutting the head with the general pick for the doub

44、le-headed or three spiral layout. Cutting head speed n = 20 ~ 65r/min, a sharp pick cutting the average speed V = 1.5 ~ 2.5m / s, cutting swing speed Vn = 0.8 ~ l0m / s. Cut-off line from t = 20 ~ 50mm, (when cutting coa

45、l from the value of all-time for small value). Average single-pole/double-throw force should reach: f4 grade coal and rock F ≥ 2500 N, f6 grade coal and rock F ≥ 5000 N, f8 grade coal and</p><p>  slewing ri

46、ng size specifications. If the user does not require a cantilever stretching structure, is generally not recommended.</p><p>  4.2 shipping agencies determine the parameters</p><p>  1) Loading

47、mechanism Loading bodies and Middle conveyor used linkage or single-action mode, loading the bodies rake claws speed is generally 25 ~ 48 r / min. Star Ferry's speed can be slightly higher than some. Using direct-dri

48、ve hydraulic motors, the maximum output torque rated torque for calculating the value of 1.5 times. Shovel coal-general of the tilt angle to 21 ° ~ 25 °, it should be the width of track, spacious than the 0.6 ~

49、 1.2 m, declining position should not be less than the minimum </p><p>  4.3 running track and identify the technical parameters of connectivity between</p><p>  a)walking track drivers and tran

50、smission patterns have the following two ways, the overall design and layout determined at the time one of them. 1) Drive a motor-driven than reducer (i ≈ 250) → led initiative sprocket. Can only establish a walking spee

51、d of 5 ~ 7.5 m / min. 2) The speed of a hydraulic motor torque direct drive or take the initiative sprocket of a slowdown in high-speed motor driven me a sprocket can take the initiative to achieve rapid mobilization and

52、 the need to slow operations</p><p>  wear small chain of contacts. Heavy and severe roadheader recommend using this structure type. Track-installed at the bottom of the supporting wheels, each bearing capac

53、ity should be not less than 50 percent of weight, distance is generally tracked the plate pitch 1.5 times.</p><p>  4.4 the hydraulic system of technical parameters established</p><p>  Hydrauli

54、c system of technical parameters should be determined in the hydraulic design calculations. The pressure should not be rated higher than the 20 ~ 25 MPa. A hydraulic motor in the system should be set up power transmissio

55、n cooler, the system in the optional round series at the pump, rated pressure announced that the following 20 MPa. Selection of pumps and motors of the Anyu should be around 1.5. Each loop system in the pressure relief v

56、alve is set for the rated pressure of 1.8 to 2.2 tim</p><p>  4.5 electronic control system identified the main technical parameters</p><p>  Electronic control system of power supply voltage sh

57、ould be roadheader models to determine the size of pressure levels, special light, light machine should be elected 660 V, medium and heavy aircraft should be elected 660 V/1140V. Some momentum in the electrical circuit c

58、omponents, the power supply should meet the range of 70% to 115% of the requests.</p><p>  4.6 other supporting systems</p><p>  1) Spray system, cutting nozzles installed in the front organizat

59、ions cantilever pressure for 1.5 MPa. Spray nozzle within the system installed in cutting the first pick in the back seat of the spray system pressure of not less than 4 MPa. Cutting rock on the case should be to increas

60、e water pressure and water. 2) Inside and outside the water spray system shall not exceed the actual health roadheader capacity of 6 to 8 percent, or stagnant water in the face of slime.</p><p>  5 the overa

61、ll calculation of the necessary plans and systems</p><p>  Such as in roadheader design and overall layout is complete with two of the main components of each system and the main structure, the basic technic

62、al parameters have been determined, theComplete machine should carry out the necessary calculations and the overall system, and other plans. 1) Cutting agencies roadheader static and dynamic stability of the calculation.

63、 2) Transmission and hydraulic components of the electronic control system of power calculation.</p><p>  3) Hydraulic system heat balance calculations. 4) Drawing transmission, hydraulic, electronic control

64、 system plans. 5) Drawing cutting sections of roadway.</p><p>  6 Conclusion</p><p>  Roadheader design is roadheader design projects in the technical design of the components. It is the key to

65、the design of the overall performance parameters of reasonable choices, the assembly of each system and optimize the design standards, in particular, cutting the cutting technology is particularly important. Roadheader d

66、escribed in this paper, the overall design is still based on traditional design, dynamics, kinematics, the calculation of the force should be wider use of modern design met</p><p><b>  譯文:</b><

67、;/p><p>  懸臂縱軸式掘進機的總體設(shè)計</p><p>  總體設(shè)計是機械產(chǎn)品設(shè)計過程中的重要內(nèi)容和主要環(huán)節(jié), 它是在方案設(shè)計之 后緊接著進行的設(shè)計工作。 懸臂縱軸式掘進機(以下簡稱掘進機)的總體設(shè)計對整 機性能的優(yōu)劣起著決定性的作用, 并決定了各總成、 系統(tǒng)、 各部件之間的協(xié)調(diào)性, 統(tǒng)一性和匹配關(guān)系,從而獲得總體的高端 性能和較好的技術(shù)經(jīng)濟效益。 掘進機的總體設(shè)計,主要包括以下內(nèi)容:

68、 1)據(jù)設(shè)計任務(wù)書選擇機型及各部件結(jié)構(gòu)型式 2)定整機的主要技術(shù)性能參數(shù),包括尺寸參數(shù)、重量參數(shù)、運動參數(shù)和技 術(shù)經(jīng)濟指標(biāo) 3)按照總體設(shè)計的性能要求,確定整機系統(tǒng)的組成 及它們之間的匹配性以 及各個部件的主要技術(shù)參數(shù) 4)進行必要的總體計算,并繪制傳動、液壓、電控系統(tǒng)圖等。</p><p>  1.選定該機型和各個部件及其結(jié)構(gòu)型式、驅(qū)動方式、并進行總 體的合理布置</p><p>  該

69、項內(nèi)容在確定前,首先應(yīng)滿足設(shè)計任務(wù)書的內(nèi)容,特別是用戶提出的主要 要求經(jīng)過調(diào)研,雙方反復(fù)交換意見,達到既能滿足用戶(或上級)條件,又能較好 的符合本企業(yè)產(chǎn)品發(fā)展的總體規(guī)劃。</p><p><b>  1)機型的選定</b></p><p>  根據(jù)掘進機的用途, 是用于煤礦井下巷道的掘進還是用于其他行業(yè)的工程作 業(yè),掘進機的工作條件是用于截割煤巷還是半煤巖巷,煤巖的

70、單向抗壓強度(或 普氏系數(shù) f 值)及巖石的磨蝕系數(shù)。同時應(yīng)對照行標(biāo) MT138~1995《懸臂式掘進機 的型式與參數(shù)》 ,按其截割煤巖的最大單向抗壓強度,選定機型的類別。</p><p>  2)各部件結(jié)構(gòu)型式、驅(qū)動方式的確定</p><p>  掘進機一般由截割機構(gòu)、裝運機構(gòu)、行走機構(gòu)、液壓系統(tǒng)、電控系統(tǒng)及輔助 裝置(如除塵裝置、安全裝置、遙控 監(jiān)測裝置)等組成。 a.截割機構(gòu)。截割機

71、構(gòu)的驅(qū)動方式由交流電動機驅(qū)動,在傳動系統(tǒng)中一般 設(shè)齒形聯(lián)軸節(jié),不設(shè)機械式過載保護裝置,經(jīng)兩級行星減速器帶動主軸前端的截 割頭。 部分?jǐn)嗝婢蜻M機的工作機構(gòu)有截鏈?zhǔn)?、圓盤銑削式和懸臂截割式等。因懸臂 截割式掘進機機體靈活、體積較小,可截出各種形狀和斷面的巷道,并能實現(xiàn)選 擇性截割,而且截割效果好,掘進速度較高;所以,現(xiàn)在主要采用懸臂截割式, 并已成為當(dāng)前掘進機工作機構(gòu)的一種基本型式。</p><p>  按截割頭的布

72、置方式,分為縱軸和橫軸式兩種。 縱軸式截割頭的優(yōu)點是:傳動方便、結(jié)構(gòu)緊湊,能截出任意形狀的斷面,易 于獲得較為平整的斷面,有利于采用內(nèi)伸縮懸臂,可挖柱窩或水溝。截割頭的形 狀有圓柱形、圓錐形和圓錐加圓柱形,由于后兩種截割頭利于鉆進,并使截割表 面較平整,故使用較多。這種工作機構(gòu)的缺點是:由于縱軸式截割頭在橫向擺動 截割時的反作用力不通過機器中心,與懸臂形成的力矩使掘進機產(chǎn)生較大的振 動, 故穩(wěn)定性較差。 因此, 在煤巷掘進時, 需加大機

73、身重量或裝設(shè)輔助支撐裝置。 目前,這種掘進機在部分?jǐn)嗝婢蜻M機中使用較多。 b.裝運機構(gòu)。它一般由裝載機構(gòu)和中間輸送機組成。它們可采用分別驅(qū)動 或集中聯(lián)動方式,既可用交流電動機驅(qū)動,也可用液壓馬達驅(qū)動。 耙爪式是利用一對交替動作的耙爪來不斷地耙取物料并裝入轉(zhuǎn)載運輸機構(gòu)。 這種方式結(jié)構(gòu)簡單、工作可靠、外形尺寸小、裝載效果好,目前應(yīng)用很普遍。但 這種裝載機構(gòu)寬度受限制(因為掘進機工作時履帶行走機構(gòu)一般不調(diào)動) 。為擴 大裝載寬度,可使鏟板連同

74、整個耙爪機構(gòu)一起水平擺動,或設(shè)計成雙耙爪機構(gòu), 以擴大裝載范圍。 星輪式機構(gòu)比耙爪式簡單、強度高、工作可靠,</p><p>  斷面掘進機通常采用履帶式行走機構(gòu)。兩條履帶分別由各自的動力來驅(qū)動,可實 現(xiàn)原地轉(zhuǎn)向。履帶的驅(qū)動動力有電動機和液壓馬達兩種,電動機驅(qū)動一般只設(shè)置 一種行走速度,液壓馬達驅(qū)動可采用低速大扭矩馬達直接帶動履帶鏈輪,或采用 中速液壓馬達減速器帶動履帶鏈輪的傳動方式,它可實現(xiàn)無極調(diào)速。 履帶結(jié)構(gòu)

75、型式有滑動和滾動兩種,當(dāng)機器調(diào)動速度≤10m/min 的中、輕型掘 進機,宜采用滑動結(jié)構(gòu)型式;當(dāng)機器的調(diào)動速度>10m/min 的重型、特重型掘進 機,應(yīng)采用滾動結(jié)構(gòu)型式。 d.液壓系統(tǒng)。液壓系統(tǒng)多采用開式系統(tǒng)多路閥集中控制(直接操縱或遙控操 縱)方式。以往國內(nèi)外多采用齒輪泵,近年來掘進機液壓系統(tǒng)采用柱塞泵有增多 的趨勢。 e.電控系統(tǒng)。電控系統(tǒng)包括動力部分、控制部分和檢測部分。電控系統(tǒng)必 須按照煤礦井下防爆要求設(shè)計、制造、檢驗,

76、必須符合 GB3836-2000 標(biāo)準(zhǔn)中的 有關(guān)規(guī)定和要求。為了提高掘進機在作業(yè)時的安全性,操作的靈活性 以及機械 傳動部分的故障診斷及監(jiān)控功能,從實用角度考慮,裝設(shè)必要的離機遙控裝置、 測控壓力、溫度、液位及關(guān)鍵部位的故障診斷裝置。</p><p><b>  3)總體布置</b></p><p>  總體布置的內(nèi)容包括以下幾個方面: (1)確定各部件在整機說的位置

77、,并對外形尺寸提出要求; (2)確定各部件、部件與整機之間的連接方式; (3)估算整機重量,并對各部件的重量提出要求; (4)布置各操縱機構(gòu)、司機座位等; (5)審核個運動部件的運動空間,排除可能發(fā)生的運動干涉。</p><p><b>  4) 具體要求</b></p><p>  在掘進機總體布置時,需注意以下問題: (1)工作機構(gòu)減速器減速器的進、出軸盡量同軸線

78、; (2)懸臂和鏟板的尺寸關(guān)系相適應(yīng),既有利于裝載,又要避免截割頭截割 鏟板; (3)懸臂的水平和垂直擺動中心的位置可以重合,也可以不重合。從增加 機器的穩(wěn)定性看,擺動這些都高度應(yīng)盡量降低。在保證懸臂不與其他機構(gòu)干涉的 條件下, 擺動中心的位置應(yīng)盡量靠后, 但必須保證中心在機器的縱向?qū)ΨQ平面內(nèi); (4)當(dāng)各主要部件設(shè)計出來之后。應(yīng)進行校核,不滿足需求時需僅需調(diào)整, 使重心位于履帶中心稍偏前且小于 L/6(L 為履帶接地長度) 。此外,還

79、需求重心 位置在截割機構(gòu)回轉(zhuǎn)臺中心線之后,而且重心高度越低越好,以提高機器作業(yè)時 的穩(wěn)定性。</p><p>  (5)總體布置應(yīng)考慮左右兩側(cè)重量對稱并照顧工作習(xí)慣及方便操作。司機 座一般設(shè)在機身左側(cè)、且位于機身后部,座椅高度應(yīng)保證司機的視線,使其哪個 很好地操縱機器,截割出規(guī)則的巷道; (6)操縱臺位置要適當(dāng),應(yīng)保證司機操縱方便、省力。儀表顯示裝置的位 置要便于司機觀察,又不分散司機正常操作的注意力。</

80、p><p>  5)傳動型式及動力元件的選擇</p><p>  a.傳動型式及元件選擇應(yīng)遵循的原則 (1)技術(shù)先進性:能夠改善機器性能,提高生產(chǎn)率; (2)經(jīng)濟合理性:傳動系統(tǒng)盡量簡單、元件少,易加工,價格低,維修容 易,使用壽命長; (3)工作可靠性:傳動系統(tǒng)的可靠性表現(xiàn)為元件使用壽命,因此也是對元件 質(zhì)量的要求; (4)適應(yīng)性:元件應(yīng)適應(yīng)傳動系統(tǒng)的載荷、工況及環(huán)境等條件的要求。 b.各機

81、構(gòu)對傳動系統(tǒng)的要求及傳動型式的選擇 掘進機的截割、裝載、運輸、行走等機構(gòu)一般均為分別傳動,各部件受力狀 態(tài)及工作條件不同,因而傳動型式有不同的要求。 (1)工作機構(gòu)要求有較大的短時過載能力,而油馬達對沖擊負荷很敏感, 過載負荷能力低,影響截割頭正常連續(xù)運轉(zhuǎn)。所以,掘進機的工作機構(gòu)宜采用電 動機為動力的機械傳動型式。應(yīng)利用體積小、功率大、過負荷能力強的專用電動 機,并配備可靠的電氣保護裝置。根據(jù)工作機構(gòu)結(jié)構(gòu)緊湊的特點,通常工作機構(gòu) 的減速

82、器設(shè)在懸臂內(nèi),成為懸臂的組成部分。截割頭調(diào)速方式一般采用配換掛輪 的方法,變速機構(gòu)力求簡單。 (2)耙裝機構(gòu)傳動裝置的特點是:減速器需裝在尺寸有限的鏟板下部,因 而設(shè)計空間較小, 工作條件惡劣。 減速器經(jīng)常浸泡在煤巖泥水中, 卡料</p><p>  方式采用機械液壓制動方式。這種傳動方式傳動可靠性高,電動機價格低,維修 容易,但不能調(diào)速,減速箱體積較大,巷道淋水大時,電動機易受潮而燒毀。 履帶行走機構(gòu)采用液壓傳

83、動型式,系統(tǒng)簡單、性能較好、技術(shù)先進。液壓傳 動的行走機構(gòu)中,在液壓馬達型式選擇及調(diào)速方式設(shè)計方面,有不同的方案。 采用低速大扭矩馬達驅(qū)動,其特點是系統(tǒng)簡單,尺寸小、重量輕,能夠?qū)崿F(xiàn) 無級調(diào)速及過載自動保護。但液壓馬達傳動復(fù)雜、制造費用高,維護較難。 采用齒輪油馬達,容積效率高,耐沖擊性能好,維修容易,造價較低,一臺 10KW 左右齒輪油馬達的價格只有同功率徑向柱塞馬達的 1/10;尺寸小、重量輕。 一臺 10KW 左右齒輪油馬達的重量

84、,僅為同功率低速大扭矩馬達的 1/18,為電動 機重量的 1/13。采用齒輪油馬達后,減速器尺寸雖然較低速大扭矩馬達的大, 但較電動式的?。∕RH-S50-13 型機的減速器傳動比 i=328) 。因此可方便地將馬 達、減速器、液壓制動閥、緊鏈裝置等安裝于履帶架中間。這種方式在技術(shù)性能 上優(yōu)于機械傳動, 在經(jīng)濟指標(biāo)上優(yōu)于低速大扭矩馬達傳動。 因此具有獨特的優(yōu)點。 行走機構(gòu)的調(diào)速方式有兩種,一種</p><p> 

85、 2.確定整機主要技術(shù)參數(shù)</p><p>  掘進機整機主要技術(shù)參數(shù)包括尺寸參數(shù) (長×寬×高)、重量參數(shù)、運動參 數(shù)和動力參數(shù)。</p><p><b>  1)尺寸參數(shù)</b></p><p>  整機長度、寬度的大小直接與其轉(zhuǎn)彎半徑有關(guān),推薦輕型機長度≤7.5m, 中型機長度≤8.5m,重型機≤l0m,對應(yīng)的寬度分別

86、為≤1.6m,≤2.5m,≤3m。 整機的高度直接關(guān)系到它的動、靜態(tài)穩(wěn)定性,適應(yīng)范圍和通過性的好壞,因 此越低越好。當(dāng)今中外機型發(fā)展趨勢是矮機型,中、重型機高度 1.6~2m,特輕 型、輕型機的高度 1.4~1.6m。掘進機可掘巷道斷面的最大、最小高度和寬度應(yīng) 滿足設(shè)計任務(wù)書的要求。臥底深度 250~400mm,離地間隙 C=B/13+84(mm),B 為兩 履帶中心距)。中間輸送機龍門口過料高度最好為 400mm,履帶接地長度 L 與

87、其 中心距 B 之比應(yīng)為 L/B≤1.6。</p><p><b>  2)重量參數(shù)</b></p><p>  整機自重是掘進機的—個重要參數(shù),機重太輕,工作穩(wěn)定性下降,擺動截割 時會發(fā)生擺尾現(xiàn)象、截割效率下降,截齒磨耗率增加;機重太重時,機動性差, 轉(zhuǎn)向靈活性下降?!闼淖灾乜砂?w=(t)估算,式中 N 為截割機構(gòu)功率,kW; V 為截割頭平均截割速度,m/s

88、;也可參照現(xiàn)有掘進機用類比法來確定,機重(t) 與截割功率 (kW) 之比為 0. 25~0. 對于一般煤、 4。 巖底板, 許用值</p><p><b>  ≤0.14MPa;</b></p><p>  對于水軟化的泥質(zhì)頁巖底板,</p><p><b>  ≤0.05MPa。</b></p><

89、p><b>  3)運動參數(shù)</b></p><p>  截割機構(gòu)的運動參數(shù):截割頭的平均截割速度 V:對煤巖的單向抗壓強度 σ c ≤ 40MPa,V=3~3.5m/s; σ c ≤ 60MPa,V=2~2.5m/s, σ c >60MPa.V=l~2m/s。 但最終切割速度由切割技術(shù)來確定。</p><p><b>  4)動力參數(shù)</

90、b></p><p>  掘進機驅(qū)動的動力源都采用交流電動機。截割機構(gòu)功率大小。實際上一般采 用類比法,再結(jié)合掘進機一些個性因素及經(jīng)驗來確定。 掘進機在作業(yè)過程中,縱軸式和橫軸式部需要足夠的掏槽推進力和擺動(水 平方向和垂直方向)力。 根據(jù)俄羅斯(原蘇聯(lián))在實驗室的試驗結(jié)果得知,截割煤巖的普氏硬度 f=4~6(相當(dāng)于 0 C=40~60MPa),研磨系數(shù) F=5~7mg/mm2。截割時的擺動力 (牽 引力)

91、Pv=(1~1.34)P,P=M/Rcp,式中 P 為截割頭上的平均截割力;Rcp 為截 割頭平均半徑; 為截割頭上的額定扭矩。 M 掏槽時的進給力(軸向推力)R; (1.8~ 2.5)Pv,此力不得大于履帶對底板打滑時的極限牽引力。</p><p><b>  5)技術(shù)經(jīng)濟指標(biāo)</b></p><p>  Q=(m3/min),式中 sx 為截割頭的縱向橫截面積,m

92、2:Vn 為截割頭的截割擺 動速度,m/min。 掘進機的設(shè)計壽命,在國際上先進的產(chǎn)品可達 3~5 年,在此期間它無需升 井大修,國內(nèi)產(chǎn)品一般為 1~2 年。</p><p>  3.按照總體設(shè)計的要求。 確定各主要部件參數(shù)及其相互之間的連 接關(guān)系</p><p>  1)截割機構(gòu)技術(shù)參數(shù)的確定及其連接關(guān)系</p><p> ?。?)截割機構(gòu)技術(shù)參數(shù)的確定截割頭上的

93、截齒排列一般為雙頭或三頭螺旋 線布置方式。 截割頭轉(zhuǎn)速 n=20~65r/min, 截齒尖的平均截割速度 V=1. 5~2. 5m /s,截割擺動速度 Vn=0.8~l0m/s。截線距離 t=20~50mm,(切煤時取大值, 切巖時取小值)。 平均單刀力應(yīng)達到: 級煤巖 F≥2500N, 級煤巖 F≥5000N, f4 f6 f8 級煤巖 F≥12000N,截齒安裝角最佳為 45°~48°。 (2)截割機構(gòu)的連接 截

94、割機構(gòu)懸臂安裝在叉形架前端,叉形架固定在回轉(zhuǎn)臺上,回轉(zhuǎn)臺固定在機 架上。根據(jù)截割機構(gòu)在作業(yè)過程中的作用力和力矩,應(yīng)用 MT475-1996《懸臂式 掘進機回轉(zhuǎn)支承型式、基本參數(shù)和技術(shù)要求》選定回轉(zhuǎn)支承的結(jié)構(gòu)型式,通過計 算確定回轉(zhuǎn)支承規(guī)格尺寸。如用戶對懸臂不要求有伸縮結(jié)構(gòu),一般不推薦采用。</p><p>  2)裝運機構(gòu)參數(shù)的確定</p><p>  (1)裝載機構(gòu) 裝載機構(gòu)與中間輸送機

95、采用聯(lián)動方式或單動方式, 裝載機構(gòu)耙爪的轉(zhuǎn)速一般 為 25~48r/min。星輪的轉(zhuǎn)速可略高一些。采用液壓馬達直接驅(qū)動時,最大輸出 扭矩應(yīng)為計算額定扭矩值的 1.5 倍。鏟煤板的傾斜角一般為 21°~25°,它 的寬度應(yīng)比履帶外寬大 0.6~1.2m,下降最低位置不應(yīng)小于臥底深度上升最大高 度應(yīng)達到 350~400mm。 (2)中間輸送機 中間輸送機的鏈條可采用單鏈或雙鏈結(jié)構(gòu)形式的圓環(huán)鏈,鏈速不應(yīng)超過 0.92m/s

96、,鏈條采用美國萬向套筒滾子鏈單鏈時,鏈速不應(yīng)超過 2.5m/s,一般取 1.6~2m 為了滿足卸載高度的變化要求,機尾應(yīng)設(shè)多級升降液壓缸實現(xiàn)升降,升 起時的最小高度應(yīng)為受料斗高度加 300mm 左右。如機尾需要左右擺動時,必須采 用一條美國萬向套筒滾子鏈, 在轉(zhuǎn)向位置的一側(cè)設(shè)置單作用液壓缸實現(xiàn)機尾左右 擺動 45°,以擴大卸載的寬度。</p><p>  3)行走履帶技術(shù)參數(shù)的確定和連接關(guān)系</p

97、><p>  a.行走履帶的驅(qū)動型式和傳動方式有兩種, 總體設(shè)計和總體布置時確定其中 一種。 (1)電動機驅(qū)動一大傳動比減速器(i≈250)→帶動主動鏈輪。 一般只能確定一種行走速度 5~7.5m/min。 (2)速大扭矩液壓馬達一直接驅(qū)動主動鏈輪或中高速馬達一減速箱一帶動主 動鏈輪能實現(xiàn)快速調(diào)動和慢速作業(yè)的需要, 行走速度為 0~10m/min 的無級調(diào)速。 b.履帶傳動的連接關(guān)系 結(jié)構(gòu)型式有滑動和滾動兩種 ,滑動

98、式結(jié)構(gòu)簡單,內(nèi)阻較大,對特輕型、輕 型、中型掘進機推薦采用滑動結(jié)構(gòu)式。滾動式運行阻力較小,履帶架底部與履帶 鏈相接觸磨損小。重型和特重型掘進機推薦采用這種結(jié)構(gòu)型式。履帶架底部裝設(shè) 的支重輪,每個承載力應(yīng)不小于機重 50%,間距一般為履帶板節(jié)距的 1.5 倍。</p><p>  4) 液壓系統(tǒng)技術(shù)參數(shù)的確定</p><p>  液壓系統(tǒng)的技術(shù)參數(shù)的確定應(yīng)在液壓設(shè)計計算后定。 系統(tǒng)的額定工作

99、壓力不 宜高于 20~25MPa。在系統(tǒng)有液壓馬達傳動動力時應(yīng)設(shè)置冷卻器,系統(tǒng)中選用串 聯(lián)輪泵時,額定壓力宣在 20MPa 以下。選用泵和馬達的安裕度應(yīng)為 1.5 左右。 系統(tǒng)中每個回路的溢流閥調(diào)定壓力為其額定壓力的 1.8~2.2 倍為宜。</p><p>  5)電控系統(tǒng)主要技術(shù)參數(shù)的確定</p><p>  電控系統(tǒng)的供電電壓應(yīng)按掘進機機型大小來確定壓等級,特輕型、輕型機應(yīng) 選 66

100、0V,中、重型機 型應(yīng)選 660V/1140V。動力部分回路中的電器元件應(yīng)滿足供 電電的波動范圍 70%~115%的要求。</p><p><b>  6)其他輔助系統(tǒng)</b></p><p>  1)外噴霧系統(tǒng),噴嘴設(shè)置在截割機構(gòu)懸臂的前端水壓為 1.5 MPa。 內(nèi)噴霧系統(tǒng)的噴嘴裝置設(shè)在截割頭截齒座的后面內(nèi)噴霧系統(tǒng)的壓力不低于 4MPa。對截割巖石的情況下應(yīng)適當(dāng)提

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