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外文文献EMERGENCY BRAKING OF A MINE HOIST IN THE CONTEXT OF THE BRAKING SYSTEM SELECTIONHAMOWANIE AWARYJNE (KRACOWE) URZDZENIA WYCIGOWEGO DOBR UKADU HAMUJCEGOThe 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 levelsResults 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 brakingW referacie przedstawiono wybrane problemy dynamiczne zwizane z awaryjnym (kracowym) hamowaniem naczy wydobywczych grniczego urzdzenia wycigowego. Bazujc na modelu urz- dzenia oraz rozwaaniach zawartych w opracowaniu autora (Wolny, 2016) podano wzory analityczne z pomoc ktrych mona wyznaczy parametry ukadu hamujcego, ktrego zastosowanie do awaryjnego (kracowego) hamowania, gwarantuje e:maksymalne obcienie lin nonych nie przekroczy wartoci siy zrywajcej liny,opnienie hamowanych naczy nie przekroczy opnienia dopuszczalnego.Wyniki analizy dynamicznej pracy urzdzenia wycigowego w warunkach hamowania (kracowego) awaryjnego, zawarte w referacie mog stanowi podstawy do poprawnego zaprojektowania np. elementw zawiesze naczy i lin wyrwnawczych, rwnie z wykorzystaniem metod wytrzymaoci zmczeniowej, dla konkretnych parametrw eksploatacyjnych wycigu (Eurokod 3).Sowa kluczowe: wycig grniczy, dynamika, obcienia, hamowanie awaryjne*AGH UNIVERSITY OF SCIENCE AND TECHNOLOGY, AL. MICKIEWICZA 30, 30-059 KRAKOW, POLAND1.IntroductionEmergency 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 systems 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 mPKPh0Fig. 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 distance2.Emergency braking of mine hoistsThe 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 effectsIn 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 levels3.1.Maximal loads acting on the rope section between the conveyance being arrested in the headgear tower and the Keope pulleyLoads 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 ropesE 1,1 105 MPa modulus of elasticity (the velocity of elastic wave propagation in ropes is calculated based on this value)l1= (3050) 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 0,81,2 1/s and l1/2a ranges from 4 to 7 103 s.Thus, the value of the expressionfalls in the range (13.75) 103 for most hoist installations operated in Polish collieries. Accord- ingly, inequality (9) becomesThe 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 arrestedAnother 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:whereadop 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 0 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 (0,81,2) 1/s and l1/2a is in the range (47) 103 s, the value of the expressionwill fall in the range 0.220.32Substituting 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-upTh 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 operationalparameters of the hoisting installation.ReferencesKlich A., 1980. Modellerung Schachtfrdranlagen fr Grosse lasten und Teufen. Archiwum Grnictwa, 25, 2.Knop H., 1975. Wybrane zagadnienia z dynamiki urzdze wycigowych. ZN AGH, Elektryfikacja i Mechanizacja Grnictwa i Hutnictwa, Z 67, Krakw.Wolny S., 1988. Teoretyczne rozwaania nad procesem hamowania kracowego naczy wydobywczych wycigw ko- palnianych. ZN AGH. Mechanika, z. 11. Krakw 1988.Wolny S., 2003. Wybrane problemy wytrzymaociowe w eksploatacji grniczych urzdze wycigowych. Monografia.Problems of mechanical engineering and robotics, No 20, Krakw 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.Rozporzdzenie Ministra Gospodarki z dnia 28 czerwca 2002 r. w sprawie bezpieczestwa i higieny pracy, prowadzenia ruchu oraz specjalistycznego zabezpieczenia przeciwpoarowego w podziemnych zakadach grniczych.Eurokod 3. Projektowanie konstrukcji stalowych (w zastpstwie normy PN-90/B03200).中文翻译矿井提升机的紧急制动是在制动系统选择的背景下进行的HAMOWANIE AWARYJNE(KRACOWE)URZDZENIA WYCIGOWEGODOBOR UKADU HAMUJCEGO本文对矿用升降机在紧急制动阶段的动态特性进行了选择。根据作者(Wolny, 2016)提供的升降机模型和理论背景支持，推导出制动系统参数的解析公式，在紧急制动时应保证:-吊绳的最大载荷不应超过断绳力，-被停止的输送带的减速不应超过允许的水平矿井提升机的动态分析的结果的行为在紧急制动阶段总结在本研究中可以利用支持交通工具的设计和绳疲劳耐久附件的方法,目的是适应指定的起重安装的操作参数(Eurokod 3)。关键词:矿井提升机;动力学;装载W referacie przedstawiono wybrane problemy dynamiczne zwizane z awaryjnym (kracowym) hamowaniem naczy wydobywczych grniczego urzdzenia wycigowego. Bazujc na modelu urz- dzenia oraz rozwaaniach zawartych w opracowaniu autora (Wolny, 2016) podano wzory analityczne z pomoc ktrych mona wyznaczy parametry ukadu hamujcego, ktrego zastosowanie do awaryjnego (kracowego) hamowania, gwarantuje e: maksymalne obcienie lin nonych nie przekroczy wartoci siy zrywajcej liny, opnienie hamowanych naczy nie przekroczy opnienia dopuszczalnego.Wyniki analizy dynamicznej pracy urzdzenia wycigowego w warunkach hamowania (kracowego) awaryjnego, zawarte w referacie mog stanowi podstawy do poprawnego zaprojektowania np. elementw zawiesze naczy i lin wyrwnawczych, rwnie z wykorzystaniem metod wytrzymaoci zmczeniowej, dla konkretnych parametrw eksploatacyjnych wycigu (Eurokod 3).Sowa kluczowe: wycig grniczy, dynamika, obcienia, hamowanie awaryjne1. 介绍当制动力直接作用于已经开始超速行驶的输送机时，紧急制动周期已受到研究者的极大关注(Wolny, 1988, 2003)。然而,没有提供分析公式可以用于确定制动系统的参数,使其保证起重绳的最大负荷不应超过绳破断力,减速停止的交通工具不应超过可接受的水平。这句话指的是分析螺柱，只是因为有人试图用数值方法来处理这个问题(Klich, 1980)。数值数据:可以推导出在紧急制动条件下，在制动系统的预定参数条件下，所选模型点的位移，尽管模型的精度也必须考虑在内。虽然对从业者有用，但很明显，这种解决方案不能用于分析系统对输入参数(制动系统的参数)的变化的敏感性，在紧急刹车时，如果发生了超速行驶。本研究重点是找到一个解析解提出问题,或者换句话说,它的目的是为了确定位移起重和尾绳的两个交通工具在紧急制动阶段cross-profiles制动系统的功能参数的分析方法。解决方案以理论背景为基础，采用工作中提供的提升模型(Wolny, 2016)。本研究仅限于利用图1所示的系统，求在紧急制动情况下，作用于提升绳索和输送带的最大载荷。制动系统的这一特性得到了波兰和全世界广泛使用的制动系统解决方案的动态测试结果的证实(Wolny, 2003)。tg=k(k0)l0 (L0)lh mPKPh图1所示。制动系统的动态特性;l0 (L0) -制动力增加距离:K(k0) - coeffi- i表示制动力增加;t0(t0) -制动力随距离l0(l0)、Ph -制动力、lh -制动距离增加的时间2. 矿井起重机紧急制动。该工作(Wolny, 2016)提供了分析公式，推导出在紧急制动阶段，任何提升和尾绳的交叉轮廓的位移，即当制动力作用于运输时。回顾(Wolny, 2016)，这些公式可以简化形式给出，假设:这一假设适用于塔式齿轮，在实际应用中得到了验证(Knop, 1975)。因此,我们得到:结果我们得到如下等式:最后，表示钢丝绳横剖线位移的依赖关系可以写成10为:尾绳对起重绳:u *(x,t);v *(y,t)各自的位移cross-profiles尾绳,吊绳的遥远的x,y的移动坐标系统与质量相关M0、M1(t = 0)。这些位移计算坐标系统的起源的即时t = 0配合大众M0、M1和移动速度V0 =常量,这是所有起重机元素移动的速度在初始时刻,L1-在紧急制动阶段开始时，在头齿塔和Koepe滑轮之间的提升绳段的第1段长度(图1)。V0 -运输速度开始过度，AWEW, ANEN -尾索和起重索的抗拉刚度，k, k0 -分别表示塔和坑底制动力增加的系数(Wolny, 1988)。3. 紧急制动效果鉴于紧急制动的主要后果，这些方面似乎很重要:负荷作用于一小部分起重运输之间的绳索在首饰塔和ar -休息Keope滑轮,这样提升钢丝绳和滑轮之间的摩擦接触不应该被打扰,在考虑这样的事实,这绳子的长度部分可能变成零, 在头套塔或坑底被逮捕的交通工具的减速不应超过允许的水平。3.1. 最大载荷作用于在头齿轮塔和龙骨墩之间的输送带在紧急制动阶段的第一阶段(直到弹性变形波返回为止)，作用于提升钢丝绳这一段上的载荷可以得到(Wolny, 2016):在必要的转换式(3)后，回忆式(1)和(2)为:式(4)的极值为时间t，由公式给出:(4) 的极值表达式为:重新安排,我们得到:限制作用于此钢丝绳段的载荷，使其不超过钢丝绳断裂力，是制动系统参数选择的基础条件之一，保证其安全运行。这个条件可以表示为:回忆式(7)，依赖式(8)给出参数k的值，控制过动区域制动系统的行为，保证其正确的性能，防止断绳。控制头传动装置的装置参数k的值为:不等式(9)涉及制动系统工程设计人员无法控制的某些提升参数，包括:a3700m在绳索弹性波传播速度瓦力E 1,1 105 MPa -弹性模量(弹性波传播速度的绳索在此基础上计算值)l1 =(3050)m -提升钢丝绳的长度之间的部分运输ar -休息首饰塔和即时的戈培轮紧急制动阶段开始(典型的塔式齿轮操作在大多数煤矿在波兰)至于其余的参数出现在公式(9),吊绳的截面,用一个和瞿依赖于负载的重量与所有必要的运输设备Qm表示为与负载的总质量为M运输,依照有关规定规定的经济部长(2002)。表达式的值AE / 2马落在0 81 2 1 / s和l1/2a范围从4到7 103 s.因此，表达式的值落在范围(1)3.75)三分对于大多数起重机安装在波兰煤矿。一致地，不平等(9)变成了表达式(11)可用于支持制动系统的选择，其中制动力增加系数k的值保证了在超跑情况下运输的安全制动，并确保绳索不会断裂。在升降机安装中，应采用3的值和l11,50米和7 -的设施的价值和l130米。根据式(9)导出制动系统参数k的精确值。3.2。车辆减速被阻止在选择制动系统参数时要考虑的另一个方面是在紧急制动时需要限制输送机的减速。对于在主塔内被逮捕的传达，这个条件可以写成: adop -可容许的输送带减速(一个在最上面，另一个在最下面)，u*(x = 0, t)-顶部运输的位移-公式(11)(Wolny, 2016)。当底层输送机发生紧急制动时，条件(12)可表示为: 式中:v*(y = 0, t) -紧急制动时底板输送机位移(由式(12)给出，y = 0替代)(Wolny, 2016)。进一步的分析应局限于对塔顶传动系统的紧急制动。式(11)(Wolny, 2016)，式(12)为: 式(14)对时间t有极限值，公式给出:因此，在紧急制动情况下，可以从公式中得到顶层输送机的极限减速:必要的替换和回忆0 h后,简化表达式(16)就变成:降低塔顶被卡输送机的减速，使其不超过允许的减速限值，是制动系统参数选择的另一个重要条件，保证其安全运行。对于在帽架塔中被扣留的传送带，这个条件可以写成:式中: adop 可容许的传动装置的减速装置，在起落架塔中停止。回顾式(18)，可以推导出参数k的取值，控制过动区域制动系统的行为，保证其正确的性能(并防止超出允许的减速水平)。将0.220.32代入(19)，我们得到:该式(21)可用于支持制动系统的选择，其中制动力增加系数k的值应保证在超车情况下运输车辆的安全制动，防止超出允许的减速水平。4. 总结通过对矿井提升机在运输超越轨情况下的动态行为进行分析，得出以下参数:作用于在塔头和Koepe滑轮之间的输送带短段上的最大载荷(包括作用于输送带附件的载荷)，输送机的最大减速(本研究仅限于寻找在塔顶被截住的输送机的最大减速)。推导出制动系统参数的解析公式，在紧急制动阶段应保证:-吊绳的最大载荷不应超过断绳力，-被停止的输送带的减速不应超过允许的水平。本研究总结的矿井提升机在紧急制动阶段的动态分析结果，可以用来支持疲劳持久度方法的输送带和钢丝绳的设计，以使其适应规定的操作提升装置参数。参考文献Klich A., 1980. Modellerung Schachtfrdranlagen fr Grosse lasten und Teufen. Archiwum Grnictwa, 25, 2.Knop H., 1975. Wybrane zagadnienia z dynamiki urzdze wycigowych. ZN AGH, Elektryfikacja i Mechanizacja Grnictwa i Hutnictwa, Z 67, Krakw.Wolny S., 1988. Teoretyczne rozwaania nad procesem hamowania kracowego naczy wydobywczych wycigw ko- palnianych. ZN AGH. Mechanika, z. 11. Krakw 1988.Wolny S., 2003. Wybrane problemy wytrzymaociowe w eksploatacji grniczych urzdze wycigowych. Monografia.Problems of mechanical engineering and robotics, No 20, Krakw 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.Rozporzdzenie Ministra Gospodarki z dnia 28 czerwca 2002 r. w sprawie bezpieczestwa i higieny pracy, prowadzenia ruchu oraz
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