提升重量64t副立井提升機選型設(shè)計含4張CAD圖,提升,晉升,重量,64,立井,選型,設(shè)計,cad 外文文獻 EMERGENCY BRAKING OF A MINE HOIST IN THE CONTEXT OF THE BRAKING SYSTEM SELECTION HAMOWANIE AWARYJNE (KRA?COWE) URZ?DZENIA WYCI?GOWEGO – DOBóR UK?ADU HAMUJ?CEGO The paper addresses the selected aspects of the dynamic behaviour of mine hoists during the emer- gency braking phase. Basing on the model of the hoist and supported by theoretical backgrounds provided by the author (Wolny, 2016), analytical formulas are derived to determine the parameters of the braking system such that during an emergency braking it should guarantee that: –the maximal loading of the hoisting ropes should not exceed the rope breaking force, –deceleration of the conveyances being stopped should not exceed the admissible levels Results of the dynamic analysis of the mine hoist behaviour during an emergency braking phase summarised in this study can be utilised to support the design of conveyance and rope attachments by the fatigue endurance methods, with an aim to adapt it to the specified operational parameters of the hoisting installation (Eurokod 3). Keywords: mine hoists, dynamics, loading, emergency braking W referacie przedstawiono wybrane problemy dynamiczne zwi?zane z awaryjnym (krańcowym) hamowaniem naczyń wydobywczych górniczego urz?dzenia wyci?gowego. Bazuj?c na modelu urz?- dzenia oraz rozwa?aniach zawartych w opracowaniu autora (Wolny, 2016) podano wzory analityczne z pomoc? których mo?na wyznaczy? parametry uk?adu hamuj?cego, którego zastosowanie do awaryjnego (krańcowego) hamowania, gwarantuje ?e: –maksymalne obci??enie lin no?nych nie przekroczy warto?ci si?y zrywaj?cej liny, –opó?nienie hamowanych naczyń nie przekroczy opó?nienia dopuszczalnego. Wyniki analizy dynamicznej pracy urz?dzenia wyci?gowego w warunkach hamowania (krańcowego) awaryjnego, zawarte w referacie mog? stanowi? podstawy do poprawnego zaprojektowania np. elementów zawieszeń naczyń i lin wyrównawczych, równie? z wykorzystaniem metod wytrzyma?o?ci zm?czeniowej, dla konkretnych parametrów eksploatacyjnych wyci?gu (Eurokod 3). S?owa kluczowe: wyci?g górniczy, dynamika, obci??enia, hamowanie awaryjne * AGH UNIVERSITY OF SCIENCE AND TECHNOLOGY, AL. MICKIEWICZA 30, 30-059 KRAKOW, POLAND 1.Introduction Emergency braking cycles when the braking force is applied directly to conveyances which have begun an overtravel have already received a great deal of attention from researchers (Wolny, 1988, 2003). However, no analytical formulas are provided which could be used to determine the parameters of the braking system such that it guarantee that the maximal loading of the hoisting ropes should not exceed the rope breaking force and that the deceleration of the conveyances being stopped should not exceed the admissible level. This statement refers to analytical stud- ies only because some attempts have been made to handle the problem by numerical methods (Klich, 1980). The numerical data: displacements of selected model points in the conditions of emergency braking in relation to predetermined parameters of the braking system can be derived, though the accuracy of the model has to be taken into account as well. Though useful for the practitioners, obviously such solutions could not be used in the analysis of the system’s sensitiv- ity to variations in input parameters (parameters of the braking system) during the emergency braking in an event of an overtravel. This study is focused on finding an analytical solution the outlined problem, or in other words, its purpose is to determine the displacements of the hoisting and tail ropes’ cross-profiles in the two conveyances during an emergency braking phase in the function of parameters of the braking system by analytical methods. The solutions are underpinned by theoretical backgrounds and use the hoist model provided in the work by (Wolny, 2016). This study is limited to finding the maximal loads acting on the hoisting ropes and decelera- tion of the conveyances in the event of emergency braking using the system whose characteristic is given in Fig. 1. This characteristic of the braking system is corroborated by the results of dynamic testing done on braking system solutions in widespread use in Poland and world-wide (Wolny, 2003). tg?=k(k0) l0 (L0) lh [m] PK Ph 0 Fig. 1. Dynamic characteristic of the braking system; l0(L0) – distance of braking force increase: K(k0) – coeffi- cient expressing the braking force increase; t0(T0) – time of the braking force increase over the distance l0(L0), Ph – braking force, lh – braking distance 2.Emergency braking of mine hoists The work by (Wolny, 2016) provides analytical formulas to derive the displacements of any cross-profiles of hoisting and tail ropes during an emergency braking phase, i.e. whilst the braking force is applied to act on the conveyance. Recalling (Wolny, 2016), these formulas can be given in a simplified form, following an assumption that: This assumption holds true for tower – type gears, which was verified in practical applica- tions (Knop, 1975). Accordingly, we get: In consequence we get the following equalities: Finally, the dependencies expressing the displacements of rope cross-profiles can be writ- ten as: – for tail ropes – for hoisting ropes: u*(x,t); v*(y,t) are respective displacements of cross-profiles of tail ropes and hoisting ropes at the distant of x, y from the mobile coordinate systems associated with the mass M0 and M1 (for t = 0). Those displacements are calculated in the coordinate systems whose origins at the instant t = 0 coincide with the masses M0 and M1 and which move at the velocity V0 = const, which is the speed with which all hoists elements move at the initial moment, l1 — length of the hoisting rope section between the conveyance being stopped in the headgear tower and the Koepe pulley at the instant the emergency braking phase begins (Fig. 1), V0 — velocity of the conveyance beginning an overtravel, AWEW, ANEN — tensile rigidity of tail ropes and hoisting ropes, respectively, k, k0 — coefficients expressing the braking force increase in the tower and at the pit bottom, respectively (Wolny, 1988). 3.Emergency braking effects In the light of major consequence of emergency braking, these aspects seem to be of key importance: ?loads acting upon a short section of hoisting ropes between the conveyance being ar- rested in the headgear tower and the Keope pulley so that the frictional contact between the hoisting rope and the pulley should not be disturbed, and in consideration of the fact that the length of this rope section may become zero, ?deceleration of conveyances being arrested in the headgear tower or at the pit bottom should not exceed the admissible levels 3.1.Maximal loads acting on the rope section between the conveyance being arrested in the headgear tower and the Keope pulley Loads acting upon this section of the hoisting rope in the first stage of the emergency brak- ing phase (until the return of the elastic deformation wave) can be obtained from the formula (Wolny, 2016): Recalling Eq. (1) and (2), after necessary transformation Eq. (3) becomes: The extreme value of the expression (4) is found for the time t, given by the formula: The extreme value of (4) is expressed by the following dependence: Rearranging,we get: Limiting the load acting upon this rope section such that it should not exceed the rope break- ing force is one of the basic conditions underlying the selection of parameters of the braking system, guaranteeing its safe operation. This condition can be expressed as: where: SZlN — force breaking the hoisting ropes. Recalling Eq. (7), the dependence (8) gives the value of the parameter k, governing the behaviour of the braking system in the overtravel zones, ensuring its correct performance and preventing rope breaking. The value of the parameter k for the device arresting the conveyance in the headgear tower is given by: The inequality (9) involves certain hoist parameters which are beyond control of those responsible for engineering design of the braking systems, including: ?a @ 3700 m – velocity of elastic wave propagation in ropes ?E 1,1 · 105 MPa– modulus of elasticity (the velocity of elastic wave propagation in ropes is calculated based on this value) ?l1= (30÷50) m – length of the hoisting rope section between the conveyance being ar- rested in the headgear tower and the Koepe pulley at the instant the emergency braking phase begins (for typical tower-type gears operated in most collieries in Poland) As regards the remaining parameters present in formula (9), the cross-profile of hoisting ropes, denoted by A and dependent on the payload Qu and the weight of the conveyance with all necessary equipment Qm, is expressed as the total mass M of the conveyance with payload, in accordance with the relevant provisions of the Regulation by the Minister of Economy (2002). The value of the expression AE/2Ma falls in the range 0,8÷1,2 1/s and l1/2a ranges from 4 to 7 · 10–3 [s]. Thus, the value of the expression falls in the range (1÷3.75) · 10–3 for most hoist installations operated in Polish collieries. Accord- ingly, inequality (9) becomes The expression (11) can be utilised to support the selection of the braking system where the value of the coefficient of braking force increase k guarantees the secure arrest of the conveyance in the event of an overtravel and ensures the rope will not be broken. The value of 3 should be adopted in the case of hoist installations where and l1 ≥ 1,50 m and the value of 7 – for installations in which and l1 ≤30m.Theexact values of the parameter k of the braking system should be derived basing on formula (9). 3.2.Deceleration of conveyances being arrested Another aspect to be considered when selecting the parameters of the braking system is the need to restrict the deceleration of the conveyance during an emergency braking. For a convey- ance being arrested in the head tower, this condition can be written as: where adop — admissible deceleration of conveyances being arrested (one in the topmost position and the other in the lowermost), u*(x = 0, t) — displacement of the top conveyance – formula (11) (Wolny, 2016). In the event of emergency braking of the bottom conveyance, the condition (12) can be expressed as: where: v*(y = 0, t) – displacement of the bottom conveyance during an emergency braking (given by formula (12) and substituting y = 0) (Wolny, 2016). Further analysis should be restricted to emergency braking of the conveyance in the headgear tower. Recalling formula (11) (Wolny, 2016), Eq (12) becomes: Designations as above. The expression (14) has its extreme value for the time t, given by the formula: Hence, the extreme deceleration of the top conveyance in the event of emergency braking can be obtained from the formula: After necessary substitutions and recalling ω0 >> h, the simplified expression (16) becomes: Reducing the deceleration of the conveyance being arrested in the head tower such that the admissible deceleration limit should not be exceeded is another major condition underlying the selection of parameters of the braking system, guaranteeing its safe operation. For the convey- ance being arrested in the headgear tower, this condition can be written as: where: adop — admissible deceleration of a conveyance arrested in the headgear tower. Recalling Eq. (18), the formula can be derived that gives the value of the parameter k, govern- ing the behaviour of the braking system in the overtravel zones, ensuring its correct performance (and preventing the admissible deceleration levels from being exceeded). Recalling that the value of AE/2Ma falls in the range (0,8÷1,2) 1/s and l1/2a is in the range (4÷7) · 10–3 s, the value of the expression will fall in the range 0.22÷0.32 Substituting into (19), we get: The expression (21) can be utilised to support the selection of the braking system where the value of the coefficient of braking force increase k should guarantee the secure arrest of the conveyance in the event of an overtravel, preventing the admissible deceleration levels from being exceeded. 4.Summing-up Th analysis of the dynamic behaviour of a mine hoist in an event of overtravel of a convey- ance was conducted to derive the following parameters: ?maximal load acting upon a short section of a hoisting rope between the conveyance being arrested in the head tower and the Koepe pulley (including the loads acting on the conveyance attachments), ?maximal deceleration of a conveyance (this study is limited to finding the maximal de- celeration of a conveyance being arrested in the head tower). Analytical formulas are derived to determine the parameters of the braking system such that during an emergency braking phase it should guarantee that: –the maximal loading of the hoisting ropes should not exceed the rope breaking force, –deceleration of the conveyances being stopped should not exceed the admissible levels. Results of the dynamic analysis of the mine hoist behaviour during an emergency braking phase summarised in this study can be utilised to support the design of conveyance and rope at- tachments by the fatigue endurance methods with an aim to adapt it to the specified operational parameters of the hoisting installation. References Klich A., 1980. Modellerung Schachtf?rdranlagen f?r Grosse lasten und Teufen. Archiwum Górnictwa, 25, 2. Knop H., 1975. Wybrane zagadnienia z dynamiki urz?dzeń wyci?gowych. ZN AGH, Elektryfikacja i Mechanizacja Górnictwa i Hutnictwa, Z 67, Kraków. Wolny S., 1988. Teoretyczne rozwa?ania nad procesem hamowania krańcowego naczyń wydobywczych wyci?gów ko- palnianych. ZN AGH. Mechanika, z. 11. Kraków 1988. Wolny S., 2003. Wybrane problemy wytrzyma?o?ciowe w eksploatacji górniczych urz?dzeń wyci?gowych. Monografia. Problems of mechanical engineering and robotics, No 20, Kraków 2003. s. 1-260. Wolny S., 2016. Loads acting on the mine conveyance attachments and tail ropes during the energency braking in the event of on overtravel. Arch. Min. Sci. 61, 2, 497-507. Rozporz?dzenie Ministra Gospodarki z dnia 28 czerwca 2002 r. w sprawie bezpieczeństwa i higieny pracy, prowadzenia ruchu oraz specjalistycznego zabezpieczenia przeciwpo?arowego w podziemnych zak?adach górniczych. Eurokod 3. Projektowanie konstrukcji stalowych (w zast?pstwie normy PN-90/B03200).  中文翻譯 礦井提升機的緊急制動是在制動系統(tǒng)選擇的背景下進行的 HAMOWANIE AWARYJNE(KRA?COWE)URZ?DZENIA WYCI?GOWEGO ——DOBOR UK?ADU HAMUJ?CEGO 本文對礦用升降機在緊急制動階段的動態(tài)特性進行了選擇。根據(jù)作者(Wolny, 2016)提供的升降機模型和理論背景支持，推導(dǎo)出制動系統(tǒng)參數(shù)的解析公式，在緊急制動時應(yīng)保證:-吊繩的最大載荷不應(yīng)超過斷繩力，-被停止的輸送帶的減速不應(yīng)超過允許的水平礦井提升機的動態(tài)分析的結(jié)果的行為在緊急制動階段總結(jié)在本研究中可以利用支持交通工具的設(shè)計和繩疲勞耐久附件的方法,,目的是適應(yīng)指定的起重安裝的操作參數(shù)(Eurokod 3)。 關(guān)鍵詞:礦井提升機;動力學(xué);裝載 W referacie przedstawiono wybrane problemy dynamiczne zwi?zane z awaryjnym (krańcowym) hamowaniem naczyń wydobywczych górniczego urz?dzenia wyci?gowego. Bazuj?c na modelu urz?- dzenia oraz rozwa?aniach zawartych w opracowaniu autora (Wolny, 2016) podano wzory analityczne z pomoc? których mo?na wyznaczy? parametry uk?adu hamuj?cego, którego zastosowanie do awaryjnego (krańcowego) hamowania, gwarantuje ?e: – maksymalne obci??enie lin no?nych nie przekroczy warto?ci si?y zrywaj?cej liny, – opó?nienie hamowanych naczyń nie przekroczy opó?nienia dopuszczalnego. Wyniki analizy dynamicznej pracy urz?dzenia wyci?gowego w warunkach hamowania (krańcowego) awaryjnego, zawarte w referacie mog? stanowi? podstawy do poprawnego zaprojektowania np. elementów zawieszeń naczyń i lin wyrównawczych, równie? z wykorzystaniem metod wytrzyma?o?ci zm?czeniowej, dla konkretnych parametrów eksploatacyjnych wyci?gu (Eurokod 3). S?owa kluczowe: wyci?g górniczy, dynamika, obci??enia, hamowanie awaryjne 1. 介紹 當(dāng)制動力直接作用于已經(jīng)開始超速行駛的輸送機時，緊急制動周期已受到研究者的極大關(guān)注(Wolny, 1988, 2003)。然而,沒有提供分析公式可以用于確定制動系統(tǒng)的參數(shù),使其保證起重繩的最大負荷不應(yīng)超過繩破斷力,減速停止的交通工具不應(yīng)超過可接受的水平。這句話指的是分析螺柱，只是因為有人試圖用數(shù)值方法來處理這個問題(Klich, 1980)。數(shù)值數(shù)據(jù):可以推導(dǎo)出在緊急制動條件下，在制動系統(tǒng)的預(yù)定參數(shù)條件下，所選模型點的位移，盡管模型的精度也必須考慮在內(nèi)。雖然對從業(yè)者有用，但很明顯，這種解決方案不能用于分析系統(tǒng)對輸入?yún)?shù)(制動系統(tǒng)的參數(shù))的變化的敏感性，在緊急剎車時，如果發(fā)生了超速行駛。 本研究重點是找到一個解析解提出問題,或者換句話說,它的目的是為了確定位移起重和尾繩的兩個交通工具在緊急制動階段cross-profiles制動系統(tǒng)的功能參數(shù)的分析方法。解決方案以理論背景為基礎(chǔ)，采用工作中提供的提升模型(Wolny, 2016)。 本研究僅限于利用圖1所示的系統(tǒng)，求在緊急制動情況下，作用于提升繩索和輸送帶的最大載荷。 制動系統(tǒng)的這一特性得到了波蘭和全世界廣泛使用的制動系統(tǒng)解決方案的動態(tài)測試結(jié)果的證實(Wolny, 2003)。 tg?=k(k0) l0 (L0) lh [m] PK Ph 圖1所示。制動系統(tǒng)的動態(tài)特性;l0 (L0) -制動力增加距離:K(k0) - coeffi- i表示制動力增加;t0(t0) -制動力隨距離l0(l0)、Ph -制動力、lh -制動距離增加的時間 2. 礦井起重機緊急制動。 該工作(Wolny, 2016)提供了分析公式，推導(dǎo)出在緊急制動階段，任何提升和尾繩的交叉輪廓的位移，即當(dāng)制動力作用于運輸時。 回顧(Wolny, 2016)，這些公式可以簡化形式給出，假設(shè): 這一假設(shè)適用于塔式齒輪，在實際應(yīng)用中得到了驗證(Knop, 1975)。 因此,我們得到: 結(jié)果我們得到如下等式: 最后，表示鋼絲繩橫剖線位移的依賴關(guān)系可以寫成—10為: ——尾繩 ——對起重繩: u *(x,t);v *(y,t)各自的位移cross-profiles尾繩,吊繩的遙遠的x,y的移動坐標系統(tǒng)與質(zhì)量相關(guān)M0、M1(t = 0)。這些位移計算坐標系統(tǒng)的起源的即時t = 0配合大眾M0、M1和移動速度V0 =常量,這是所有起重機元素移動的速度在初始時刻, L1--在緊急制動階段開始時，在頭齒塔和Koepe滑輪之間的提升繩段的第1段長度(圖1)。 V0 --運輸速度開始過度， AWEW, ANEN --尾索和起重索的抗拉剛度， k, k0 --分別表示塔和坑底制動力增加的系數(shù)(Wolny, 1988)。 3. 緊急制動效果 鑒于緊急制動的主要后果，這些方面似乎很重要: ?負荷作用于一小部分起重運輸之間的繩索在首飾塔和ar -休息Keope滑輪,這樣提升鋼絲繩和滑輪之間的摩擦接觸不應(yīng)該被打擾,在考慮這樣的事實,這繩子的長度部分可能變成零, ?在頭套塔或坑底被逮捕的交通工具的減速不應(yīng)超過允許的水平。 3.1. 最大載荷作用于在頭齒輪塔和龍骨墩之間的輸送帶 在緊急制動階段的第一階段(直到彈性變形波返回為止)，作用于提升鋼絲繩這一段上的載荷可以得到(Wolny, 2016): 在必要的轉(zhuǎn)換式(3)后，回憶式(1)和(2)為: 式(4)的極值為時間t，由公式給出: (4) 的極值表達式為: 重新安排,我們得到: 限制作用于此鋼絲繩段的載荷，使其不超過鋼絲繩斷裂力，是制動系統(tǒng)參數(shù)選擇的基礎(chǔ)條件之一，保證其安全運行。 這個條件可以表示為: 回憶式(7)，依賴式(8)給出參數(shù)k的值，控制過動區(qū)域制動系統(tǒng)的行為，保證其正確的性能，防止斷繩。 控制頭傳動裝置的裝置參數(shù)k的值為: 不等式(9)涉及制動系統(tǒng)工程設(shè)計人員無法控制的某些提升參數(shù)，包括: ?a≈@3700m——在繩索彈性波傳播速度瓦力 ·E≈ 1,1 · 105 MPa -彈性模量(彈性波傳播速度的繩索在此基礎(chǔ)上計算值) ?l1 =(30÷50)m -提升鋼絲繩的長度之間的部分運輸ar -休息首飾塔和即時的戈培輪緊急制動階段開始(典型的塔式齒輪操作在大多數(shù)煤礦在波蘭) 至于其余的參數(shù)出現(xiàn)在公式(9),吊繩的截面,用一個和瞿依賴于負載的重量與所有必要的運輸設(shè)備Qm表示為與負載的總質(zhì)量為M運輸,依照有關(guān)規(guī)定規(guī)定的經(jīng)濟部長(2002)。表達式的值A(chǔ)E / 2馬落在0 8÷1 2 1 / s和l1/2a范圍從4到7 · 10–3 [s]. 因此，表達式的值 落在范圍(1)÷3.75)·三分對于大多數(shù)起重機安裝在波蘭煤礦。一致地，不平等(9)變成了 表達式(11)可用于支持制動系統(tǒng)的選擇，其中制動力增加系數(shù)k的值保證了在超跑情況下運輸?shù)陌踩苿?，并確保繩索不會斷裂。在升降機安裝中，應(yīng)采用3的值和l1≥1,50米和7 -的設(shè)施的價值和l1≤30米。根據(jù)式(9)導(dǎo)出制動系統(tǒng)參數(shù)k的精確值。 3.2。車輛減速被阻止 在選擇制動系統(tǒng)參數(shù)時要考慮的另一個方面是在緊急制動時需要限制輸送機的減速。對于在主塔內(nèi)被逮捕的傳達，這個條件可以寫成: adop -可容許的輸送帶減速(一個在最上面，另一個在最下面)， u*(x = 0, t)-頂部運輸?shù)奈灰?公式(11)(Wolny, 2016)。 當(dāng)?shù)讓虞斔蜋C發(fā)生緊急制動時，條件(12)可表示為: 式中:v*(y = 0, t) -緊急制動時底板輸送機位移(由式(12)給出，y = 0替代)(Wolny, 2016)。 進一步的分析應(yīng)局限于對塔頂傳動系統(tǒng)的緊急制動。式(11)(Wolny, 2016)，式(12)為: 式(14)對時間t有極限值，公式給出: 因此，在緊急制動情況下，可以從公式中得到頂層輸送機的極限減速: 必要的替換和回憶ω0 >> h后,簡化表達式(16)就變成: 降低塔頂被卡輸送機的減速，使其不超過允許的減速限值，是制動系統(tǒng)參數(shù)選擇的另一個重要條件，保證其安全運行。對于在帽架塔中被扣留的傳送帶，這個條件可以寫成: 式中: adop — 可容許的傳動裝置的減速裝置，在起落架塔中停止。 回顧式(18)，可以推導(dǎo)出參數(shù)k的取值，控制過動區(qū)域制動系統(tǒng)的行為，保證其正確的性能(并防止超出允許的減速水平)。 將0.22÷0.32代入(19)，我們得到: 該式(21)可用于支持制動系統(tǒng)的選擇，其中制動力增加系數(shù)k的值應(yīng)保證在超車情況下運輸車輛的安全制動，防止超出允許的減速水平。 4. 總結(jié) 通過對礦井提升機在運輸超越軌情況下的動態(tài)行為進行分析，得出以下參數(shù): ?作用于在塔頭和Koepe滑輪之間的輸送帶短段上的最大載荷(包括作用于輸送帶附件的載荷)， ?輸送機的最大減速(本研究僅限于尋找在塔頂被截住的輸送機的最大減速)。推導(dǎo)出制動系統(tǒng)參數(shù)的解析公式，在緊急制動階段應(yīng)保證: -吊繩的最大載荷不應(yīng)超過斷繩力， -被停止的輸送帶的減速不應(yīng)超過允許的水平。 本研究總結(jié)的礦井提升機在緊急制動階段的動態(tài)分析結(jié)果，可以用來支持疲勞持久度方法的輸送帶和鋼絲繩的設(shè)計，以使其適應(yīng)規(guī)定的操作提升裝置參數(shù)。 參考文獻 Klich A., 1980. 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