BARREL COUPLINGS FOR DRUMS MVX SERIES MECHANICAL AND TRANSMISSIONS
4. APPLICATION 6. DESIGN AND CHARACTERISTICS 9. ADVANTAGES BETWEEN HOIST GEAR AND BARREL COUPLINGS 10. COUPLINGS SIZE SELECTION 14. DIMENSIONS AND PARAMETERS MVX 16. SHAFT CONNECTION TYPES 17. WEAR INDICATOR 19. MANUFACTURING PROGRAM
COMPANY PROFILE Meccanica Vimercati was founded in 1972 as a mechanical engineering workshop specialized in the production of high precision mechanical parts on behalf of third parties. Over the last twenty years, we have specialized in the production of a wide range of mechanical couplings and transmissions for an increasingly demanding clientele worldwide. In Italy, we design and produce Barrel Couplings for hoisting equipments, Gear Couplings, Special Bearing Cages. Continuous research into cutting-edge technology is one of the strengths of Meccanica Vimercati. In fact the production department can rely on the latest generation CNC machinery and tooling. Production technology follows strict rules in the pursuit of total product quality and customer satisfaction. 3
APPLICATION MVX Barrel Couplings are recommended to connect the output shaft of a gearbox with the rope drum of cranes and hoisting equipment. The MVX coupling allows to remedy the problems deriving from a rigid connection between the gearbox shaft and rope drum, eliminating the need of a third support and compensating for substantial misalignments. Thus it eliminates the difficulty of alignment during component assembly, stress concentration mainly on the gearbox shaft; high bending moments due to misalignments and subsequent damage to bearings and gears, long shut-down times due to long installation times and subsequently increasing general costs. 4
RIGID CONNECTION WITHOUT MVX BARREL COUPLINGS Fig. 1 CONNECTION WITH MVX BARREL COUPLINGS Barrel Coupling Fixed bearing Fig. 2 5
DESIGN DESIGN AND DESIGN AND CHARACTERISTICS MVX Barrel Couplings are built with special high quality steel and the perfect dimensions are guaranteed by the latest generation CNC technology. In order to guarantee easy assembly and maintenance, MVX Barrel Couplings comprise only a small number of components (Fig. 3-4) 6
Fig. 3 1 External Sleeve 2 Hub 3 Barrel rollers 4 Cover 5 Wear indicator 6 Cover screws 7 Grease connection 8 Seal 7
Fig. 4 MVX Barrel Couplings can compensate misalignments of the hub and the external sleeve thanks to hardened steel barrel rollers, positioned in the holes formed by the machining of hub and external sleeve, with high precision internal tolerance. The described design allows to achieve high torque and radial load ratings, to compensate unpredictable axial displacements and misalignments between gearbox and rope drum. 8 MVX Barrel Couplings is provided ready assembled and without lubricant. They are supplied with a corrosion protection adequate for normal storage conditions. According to Meccanica Vimercati s warranty policy the coupling hub and the external sleeve cannot be supplied separately. The coupling should be considered as a complete spare part.
ADVANTAGES BETWEEN HOIST GEAR AND BARREL COUPLINGS The first advantage of the use of a MVX Barrel Coupling instead of a gear coupling is a significant decrease in needed room. The barrel coupling is partly positioned inside the drum and it is quite narrower than the corresponding gear coupling. Barrel couplings are subjected to much lower bending stress compared to gear couplings. As barrel couplings have increased contact area, the radial load is better distributed and hence the life of the coupling is increased. The radial load is also better distributed with coupling wear. b1 b2 9
COUPLINGS SIZE SELECTION Max. torque T max [Nm] The determined torque T max to be transmitted on the basis of the installed or used capacity of the coupling must be smaller than the max. permissible torque TN max of the Barrel Coupling in accordance with Table 1. N = max. motor power [kw] n = speed of the rope drum [rpm] fs = necessary service factor for drive groups Drive group according to DIN15020 F.E.M. 1.001 fs 1Bm / 1 Am M3 / M4 1,25 T max = N 9550 n fs 2 m M 5 1,40 3 m M 6 1,60 4 m M 7 1,80 5 m M8 2,00 MAX. RADIAL LOAD F max [N] The radial load is the portion of the load that must be covered by the barrel coupling due to the payload and the weight of the cable hoist. Since the Barrel Coupling forms one of the drum bearings, it must bear part of the total load. The static load P [N] on the rope drum must be determined first before calculating the radial load F max Q = max payload under hook [N] G = load of tackle and ropes[n] z = transmission ratio of tackle ƞ = efficiency of the rope drum and tackle Efficiency η P = (Q + G) z ƞ z Slide bearing Roller bearing 2 0,92 0,97 3 0,90 0,96 4 0,88 0,95 5 0,86 0,94 6 0,84 0,93 7 0,83 0,92 8 0,81 0,91 10
Calculation of the radial load F max with multiple rope lines to the drum P = static load on the rope drum [N] W = dead weight of the rope drum [N] F max = P + W 2 2 Multiple rope lines Calculation of the radial load F max with a single rope line to the drum P = static load on the rope drum [N] W = dead weight of the rope drum [N] b = smallest distance from the rope to the middle of the barrel roller [mm] I = distance between the bearings [mm] The determined radial load F max must be smaller than the max permissible radial load Fr max of the Barrel Coupling in accordance with Table 1. ( F max = P 1- ) [ ] b + W l 2 Single rope line 11
Option for corrected radial load Fr agg [N] If the max torque TN max is smaller than the max. permissible torque TN max of the preselected barrel coupling, the max permissible radial load Fr max can be corrected or increased. The unused torque can be converted for the purporse of increasing the max permissible radial load Fr max as follows: T max = max torque. [Nm] TN max = max permissibile torque [Nm] according to Table 1 fs = necessary service factor for drive groups according to DIN15020 or F.E.M. 1.001 Fr max = max permissibile radial force [N] according to Table 1 The reverse procedure to increase the max. permissible torque if the radial load is not fully exploited, is not allowed. Fr agg = (TN max - T max ) fs + Fr max Check the geometric dimensions of the hub-shaft connection It must also be checked whether or not the diameter of the gear shaft is smaller than the max. permissible bore diameter in the barrel coupling according to Table 1. In addition, the transmitted torque related to the hub/shaft connection must be checked for all types of connection. 12
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DIMENSIONS AND PARAMETERS MVX TABLE 1 MVX TN max (Nm) Fr (N) d max [mm] d min [mm] D [mm] L [mm] L min. [mm] M [mm] B [mm] C [mm] E [mm] 2,5 6500 17500 68 38 250 95 85 90 95 159 160 5 8000 19500 80 48 280 100 85 105 110 179 180 7,5 9400 21000 90 58 320 110 95 120 125 199 200 10 14800 27000 100 58 340 125 95 135 140 219 220 13 20800 37000 115 78 360 130 95 150 160 239 240 16 26000 41000 130 78 380 145 95 170 180 259 260 20 30000 45000 136 98 400 170 95 190 200 279 280 30 38000 53000 156 98 420 175 95 210 220 309 310 40 52000 75000 185 98 450 185 120 250 260 339 340 50 77000 115000 215 98 510 220 132 290 300 399 400 60 120000 130000 235 118 550 240 132 302 312 419 420 100 170000 145000 250 138 580 260 140 341 351 449 450 150 230000 175000 295 158 650 315 143 403 415 529 530 210 330000 265000 305 168 665 330 153 418 428 544 545 260 410000 310000 315 168 680 350 153 432 443 559 560 340 500000 350000 340 198 710 380 170 455 475 599 600 420 625000 400000 385 228 780 410 170 524 539 669 670 620 770000 470000 430 258 850 450 170 583 603 729 730 820 900000 525000 455 255 940 500 191 614 634 796 800 920 1050000 550000 500 255 1025 500 191 674 694 856 860 size 2.5-60 14
F [mm] K [mm] G [mm] R [mm] e [mm] I [mm] d2 [mm] d1 i [mm] d3 [mm] Max.axial displacement [+\-mm] weight [kg] 220 42 12 2,5 31 220 15 M 12 - - 3 11 250 42 12 2,5 31 250 15 M 12 - - 3 15 280 45 15 2,5 32 280 19 M 16 - - 4 20 300 45 15 2,5 32 300 19 M 16 - - 4 25 320 45 15 2,5 34 320 19 M 16 - - 4 30 340 45 15 2,5 34 340 19 M 16 - - 4 38 360 45 15 2,5 34 360 19 M 16 168 M 16 4 50 380 45 15 2,5 34 380 19 M 16 188 M 16 4 60 400 60 20 2,5 40 400 24 M 20 215 M 20 4 82 460 60 20 2,5 48 460 24 M 20 255 M 20 6 222 500 60 20 2,5 48 500 24 M 20 270 M 20 6 154 530 60 20 2,5 50 530 24 M 20 290 M 24 6 182 580 65 25 2,5 48 600 24 M 20 350 M 24 6 280 590 65 25 4 61 615 24 M 20 365 M 30 6 324 600 65 25 4 61 630 24 M 20 375 M 30 6 350 640 81 35 4 64 660 28 M 20 395 M 30 8 415 700 81 35 4 64 730 28 M 20 445 M 30 8 575 760 81 35 4 64 800 28 M 20 500 M 30 8 720 830 86 40 4 71 875 28 M 20 570 M 30 10 1120 900 86 40 4 71 945 34 M 20 630 M 30 10 1395 size 100-150 size 210-620 size 820-920 15
SHAFT CONNECTION TYPES 0.0 PILOT 0.1 CYLINDRICAL 1.1 ONE KEYWAY 1.2 TWO KEYWAYS AT 180º 1.3 TWO KEYWAYS AT 120º 1.4 TWO KEYWAYS AT 90º 2.1 CONICAL BORE ONE STRAIGTH KEYWAY 2.2 CONICAL BORE TWO STRAIGTH KEYWAYS 3.1 CONICAL BORE ONE TAPERED KEYWAY 3.2 CONICAL BORE TWO TAPERED KEYWAYS For any special requests please do not hesitate to contact our Technical Assistance Office 16
INDICATOR WEAR INDICATOR MVX Barrel Couplings are provided with a wear indicator which allows to perform preventative maintenance operations. The amount of wear in the barrel coupling can be inspected using the wear indicator by comparing the location of the center marker to the wear mark. The recommended wear limits are shown in Table 2. MVX Barrel Couplings must be replaced whenever the mark exceeds the recommended limits. The recommended wear limits shown in Table 2 are for applications in which the load is applied in only one direction (e.g. crane hoists). In the case where the coupling is loaded in both directions (e.g. travelling cranes), then the recommended wear limits (u/2) must be halved. Unless otherwise specified in the customer s order, the wear indicator marks on the coupling will be equal to the values shown in Table 2. Tab. 2 Coupling size 2,5 5 7,5 10 13 16 20 30 40 50 60 Max. wear u/2 [mm] 4 4 4 4 6 6 6 6 6 8 8 Coupling size 100 150 210 260 340 420 620 820 920 Max. wear u/2 [mm] 8 8 8 8 8 8 8 8 8 INDICATOR u/2 u 17
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MANUFACTURING PROGRAM PROGRAM Gear Couplings Barrel Roller Couplings Barrel Couplings for drums 19
MECCANICA VIMERCATI S.R.L. Via W.Tobagi, 9 20063, Cernusco sul Naviglio (MI) Italy C.F./P.Iva 03204190155 T +39 0292101473 F +39 0292104554 info@meccanicavimercati.com www.meccanicavimercati.com