Selecting Flexible Couplings Introduction to couplings Selecting the ideal coupling In the simplest of terms a coupling's purpose is to transfer rotational movement from one shaft to another. Reality is somewhat more complicated, though, as flexible shaft couplings have also to compensate for misalignment between two shafts. This ability must be balanced with the need to be pliable in the planes of misalignment while still having the torsional strength to carry out the coupling's main function. This is known as the Compliance mechanism where compliance is the capacity for allowing relative displacement. The choice of couplings available to today's engineers can be daunting, but follow our guidelines and you will arrive at the optimum coupling for your particular application. Several factors should always be taken into consideration when looking to specify flexible shaft couplings. These are torsional stiffness, backlash, torque, life and attachment system. All of these have bearing on coupling selection. 2 Does the coupling provide adequate misalignment protection? 2 Can it transmit the required torque? 2 Do I need axial motion or axial stiffness? 2 Can it sustain the required speed of rotation? 2 Will it fit within the available space envelope? 2 Can it operate at the designated ambient temperature? 2 Does it provide torsional stiffness required for positional accuracy? 2 Does it provide electrical isolation between the shafts? 2 Will it have the required life expectancy? Service Factors 2 Peak torque values quoted in the coupling performance tables apply to uniform load conditions at constant speed where there is no misalignment or axial displacement. 2 The torque capacity of flexible couplings will reduce when acceleration is present, for example, in stop/start or reversing conditions. 2 The more severe the acceleration, the greater reduction in torque capacity. 2 Sliding couplings (Oldham and UniLat) are subject to a wear rate dependent on the number of cycles completed. Peak torque must be greater than application torque x service factor Load Steady State Huco Flex B Huco Flex K Huco Flex M Huco Flex Ni Huco Flex P Huco Flex G Huco MultiBeam Huco S-Beam Huco TorqLink Huco Oldham Huco Flex - B Uni-Lat Stop/Start Reversing 1.5 1.5 1.5 1.0 1.0 1.0 1.0 1.0 1.0 - 2.0 2.0 2.0 2.0 1.5 2.0 1.5 1.5 1.5 - 2.0 2.0 2.0 2.0 1.5 4.0 2.0 2.0 2.0 - Duty (Hours/Day) Shock Shock & Reversing <1 1-2 3-5 6 - 12 >12 3.0 3.0 3.0 3.0 3.0 4.0 (Note 1) (Note 1) (Note 1) - 4.0 4.0 4.0 4.0 4.0 4.0 (Note 1) (Note 1) (Note 1) - 1.0 1.0 1.0 2.0 1.5 1.5 4.0 2.0 2.0 6.0 3.0 3.0 8.0 4.0 4.0 Note 1: Not recommended in these conditions 6 Huco Dynatork +44 (0) 1992 501900 Product Overview Universal / Lateral type Sliding Disc type Oldham Blind bored Uni-Lat Double Loop type Flex-P Universal Joints & Teleshafts Jaw Coupling Jaw coupling Friction Clutches Bevel Gearboxes Huco-Pol Single joints Vari-Tork, Polyclutch Basic clutch L-Box Double joints Basic clutch + Oldham coupling Teleshafts Polyclutch Light duty plastic universal joints and extensible drive shafts (teleshafts). Low mass, corrosion resistant, ideal where conventional steel joints would be under-utilised. Small, user-adjustable torque limiters for concentric or in-line mounting. Operate by friction using interleaved clutch plates. Small 90 drives encased in molded housings providing electrical isolation between shafts and mounting surface. The L-Box is rated for intermittent use, the T box for continuous. 1:1 & 2:1 ratios are available with the T-Box. Intermittent applications in business machines, instrumentation, lab equipment, analytical apparatus, etc., where steel joints would be under-utilised. Friction clutches interrupt rotation when the load being transmitted reaches a predetermined threshold. Used in all kinds of small drives to help protect personnel and equipment. L-box offers a compact means to route drives thru' 90. T-box offers 2 & 3 shaft configurations for multiple power offtake. Up to 1000 rpm Up to 1000 rpm slipping speed Up to 1500 rpm for T-box 10.7 Nm 60 Nm 0.68 Nm 3 to 20 6 to 32 4 & 5 (shafts) -20 to +60C -10 to +80C (when operating) -20 to +60C Yes No See General Description above Set Screw, Bonding, or Cross-Pinning Clamp or Set Screw N/A Thru' bored T-Box Thru' bored Material Options: Aluminium Stainless Steel General description General purpose, robust, easy to use 3-part couplings with replaceable wear elements. Generous radial compensation and pull-apart / re-engage facility for blind assemblies. High torque capacity and high Unique, general purpose light Exceptional flexibility in all duty couplings with generous three directions, radial, angular speed are available from this naturally balanced coupling and axial angular and radial misalignment compensation. Resist axial motion, can anchor unrestricted shafts and perform light push/pull duties. Where to use Stepper drives for most applications including positioning slides, pumps, actuators, etc. Encoder, resolver, tacho, Light power drives, pumps and potentiometer drives. Small small generators positioning slides, dosing pumps, & light drives generally. Light power drives where misalignment is small Up to 3000 rpm. Up to 3000 rpm. Up to 40,000 rpm. Speeds Up to 3000 rpm. Peak torque largest size 44 Nm 12 Nm 18 Nm 133 Nm Standard bores 2 to 30 3 to 22 3 to 16 3 to 16 Temperature range -20 to +60C -20 to +60C -40 to +100C Yes Yes Yes -40 to +80C Electrically isolating Yes Connection Clamp or Set Screw Page 28 - 30 Clamp or Set Screw Set Screw Page 26 - 27 Huco Dynatork +44 (0) 1992 501900 Page 44 Clamp or Set Screw Page 42 - 43 Page 45 - 50 Page 51 - 56 Page 57 - 58 5 Selecting Flexible Couplings Round & Keywayed Bore Details & Codes Metric mm Inch fraction Inch decimal Round bore code Metric keys Key size wxh - - - Keywayed bore code Inch keys K 1 1.588 2 - 1/16 - 0.0394 0.0625 0.0787 08 10 11 2.286 3 - - 0.0900 0.1181 12 14 - - - - 3.048 3.175 *3.969 - 1/8 5/32 0.1200 0.1250 0.1563 15 16 - - - - 4 4.763 5 - 3/16 - 0.1575 0.1875 0.1969 18 19 20 6 6.350 - 1/4 0.2362 0.2500 7 7.938 - 5/16 K - - - - - - - - - - - - - - - - - - - - - - - - each product in the product pages are standard. - - - - - - - - - - - - - - - To specify a keywayed bore, prefix the 2-digit number with a `P' for metric keyways or an `R' for an inch keyway. 22 24 - - - - - - - - - - Standard keyways are machined to 2 specifications: 0.2756 0.3125 25 27 2x2 - 8.00 - - 1/8 x 1/8 - 0.3755 P25 R27 Bore codes prefixed 'P' denote a metric keyway conforming to ISO 773/774 (BS 4235 Pt. 1). - 0.3150 28 2x2 9.00 - - P28 - 3/8 0.3543 0.3750 30 31 3x3 - 10.40 - - 1/8 x 1/8 - 0.4380 P30 R31 10 - 0.3937 32 3x3 11.40 - - P32 11 - 0.4331 33 4x4 12.80 - - P33 - 1/2 0.4724 0.5000 35 36 4x4 - 13.80 - - 1/8 x 1/8 - 0.5630 P35 R36 13 - 0.5118 37 5x5 15.30 - - P37 14 - 0.5512 38 5x5 16.30 - - P38 - 5/8 0.5906 0.6250 40 41 5x5 - 17.30 - - 3/16 x 3/16 - 0.7160 P40 R41 16 - 0.6299 42 5x5 18.30 - - P42 17 - 0.6693 43 5x5 19.30 - - P43 18 - 0.7087 45 6x6 20.80 - - P45 - 3/4 0.7480 0.7500 46 47 6x6 - 21.80 - - 3/16 x 3/16 - 0.8410 P46 R47 - 0.7874 48 6x6 22.80 - - P48 22 22.225 24 25 25.400 - 7/8 - - 1 0.8661 0.8750 0.9449 0.9843 1.0000 49 50 51 52 53 6x6 - 8x7 8x7 - 24.80 - 27.30 28.30 - - 1/4 x 1/4 - - 1/4 x 1/4 - 0.9930 - - 1.1180 P49 R50 P51 P52 R53 28 28.575 - 1-1/8 1.1024 1.1250 54 55 8x7 - 31.30 - - 5/16 x 1/4 - 1.2400 P54 R55 30 31.750 32 34.925 - 1-1/4 - 1-3/8 1.1811 1.2500 1.2598 1.3750 56 57 58 59 8x7 - 10 x 8 - 33.30 - 35.30 - - 5/16 x 1/4 - 3/8 x 1/4 - 1.3580 - 1.4830 P56 R57 P58 R59 35 38 - - 1.3780 1.4961 60 61 10 x 8 10 x 8 38.30 41.30 - - - - P60 P61 40 - 1.575 63 12 x 8 43.30 - - P63 50 50.800 55 - - 1.969 2.000 2.165 70 71 73 14 x 9 - 16 x 10 53.8 - 59.3 _ 1/2 x 1/2 - _ 2.224 - P70 R71 P73 60 63.500 65 - 2-1/2 - 2.362 2.500 2.559 75 77 78 18 x 11 - 18 x 11 64.4 - 69.4 - 5/8 x 5/8 - - 2.778 - P75 R77 P78 8 9 9.525 12 12.700 15 15.875 19 19.050 20 - - - Key size wxh - - - All shaft mounted products in this catalogue can be specified with inch and/or metric bore diameters. A standard range of sizes is listed for each product. Where physical dimensions permit, keyways may be specified at extra cost. For the sake of uniformity and avoidance of errors when ordering, bore diameters are designated with a 2-digit number which forms part of the order code. Please note that only the bore diameters listed for Bore codes prefixed 'R' denote an inch keyway conforming to BS 46 Pt. 1. In most cases, keyways prefixed 'R' are compatible with AGMA 9002-A86 but can differ in the depth of the key seat. All Huco couplings are RoHS compliant. Key width K Shaft Diameter Note that our tooling produces a key seat classified as `nominal' being a nominal clearance on standard keys Order Codes Combine the COUPLING REF in Main Product Tables with BORE REFS in Standard Bores Table. Please identify both bores e.g. 706.19.1924 Coupling ref. O B1 ref. *Not manufactured. Nearest alternative 4mm. Intermediate size available on request Huco Dynatork +44 (0) 1992 501900 O B2 ref. 7 Flex-P | Double Loop Flexible Coupling DIMENSIONS & ORDER CODES Size steel zinc plated hubs Dimensions stainless steel hubs Order Code Fasteners Max Diameter Length L +/- 1.0 Bore length Max Bores Mass kg x 10-3 Size 27 27 7.9 9.53 25 M3 48 48 12.7 12.7 92 M4 54 55 16.0 16.0 124 M5 56 56 16.0 16.0 136 M6 56 56 16.0 16.0 136 M6 047.10 - - 049.10 047.20 - - 049.20 047.30 - - 049.30 047.40 - - 049.40 - 050.40 Size Max Torque 1 (Nm) Max Torque 2 (Nm) Angular deg Radial mm Axial +/- mm 10 0.5 0.8 10 2.6 4.5 20 1.8 3 15 3.2 7.5 Flexing Element: 8.5 Fastener: 10 20 30 40 40* A/F (mm) Torque (Nm) 0.94 1.5 0.32 2.27 2.0 2.0 4.62 2.5 2.1 7.61 3.0 3.75 7.61 3.0 PERFORMANCE Materials & Finishes max misalignment/displacement Hubs: Steel 230M07 pb Zn plated + clear passivate or 30 5 8 15 3.2 40 10 18 15 3.2 11 40* 2.5 4.5 15 3.2 11 Stainless Steel 303 S31 natural finish Hytrel Steel Hub: Alloy steel, black oiled Stainless Steel Hub: stainless steel Temperature Range Torque 1 = torque at maximum displacement Torque 2 = torque at 1 deg. angular, 2mm axial and 0.5mm radial displacement -40C to +100C Maximum Rotational Speed 3000 rev/min STANDARD BORES* Size 10 +0.05/-0mm 3 3.175 4 4.763 5 20 6 6.350 7.938 8 9.525 22 24 27 28 31 32 35 36 38 40 41 42 30 40 Bore Ref 14 16 18 19 20 10 12 12.700 14 15 15.875 16 * Couplings with dissimilar bores are non-standard 44 Huco Dynatork +44 (0) 1992 501900