Cardan Shafts Selection_Wuxi Driveshafts Co. Ltd

According as standard JB5513-91, use the following methods to select SWC-Ⅰseries and SWC series universal joint shafts. Please consult us for selecting other product series.

1．Universal joint shafts are selected according to the load features, calculated torques,bearing life, and operating speed.
2．The calculated torque is acquired from Formulas (1)、 (2) or (1)、(3):

Where： Tc = Calculated torque, N·m;
T = Theoretic torque, N ·m;
Pw = Driving power, kW;
PH = Driving power, hp;
n = Operating speed, rpm；
K = Service factors (See Table 10)

Service Factors K

Service Factor Type	Driven Equipment	K
Light shock load	Generators Centrifugal pumps Ventilators Wood handling machines Belt conveyers	1.1～1.3
Medium shock load	Compressors (multi-cyl.) Pumps (multi-cyl.) Small section mills Continuous wire mills Conveyer primary drives	1.3～1.8
Heavy shock load	Marine transmissions Transport roller tables Continuous tube mills Continuous working roller tables Medium section mills Compressors (single-cyl.) Pumps (single-cyl.) Mixers Presses Straightening machines Crane drives Ball mills	2～3
Extra heavy shock load	Paper machines Crane accessory drives Crushers Reversing working roller tables Reeling drives Scale breakers Blooming stands	3～5
Extreme shock load	Feed roller drives Plate shears	6～15

3．Generally, universal joint shafts are selected according to the torque to be transmitted and the required bearing life. They can also be selected by checking their torque strengths or bearing life with relation to the requirements of the applicable equipment.
3.1 Checking the torsional strength using Formula (4), Tc ≤ Tn or Tc ≤ Tf or Tc ≤ TP ................ (4)
Tc = Calculated torque, N·m
Tn = Nominal torque, N·m (i.e., a theoretically calculated value under these pre-determined conditions: speed of shaft n≈10 rpm, deflection angle β = 3°, and a bearing life
LN = 5000 hours under even Icad).
Tf = Permissible torque according to the fatigue strength under alternating loads, N·m
TP = Permissible torque according to the fatigue strength under pulsating loads, N·m
TP＝1.45Tf

3.2 Checking the bearing life Using Formula (5)

LN = Service life, hrs;
n = Operating speed, rpm;
β= Joint operating angle in operation, (°);
K1 = Prime motor factor
Electric motor: K1 = 1
Diesel generator: K1 = 1.2
KL = Bearing capacity factor (See Table 11);
Lmin = Min. bearing life, hrs;
T = Theoretic torque,kN·m

Bearing Capacity Factor

design	KL	design	KL	design	KL	design	KL
SWC－Ⅰ58	0.022×10-5	SWC160	0.16	SWC440	8.25×103	SWCL225	9.79
SWC－Ⅰ65	0.012×10-4	SWC180	0.51	SWC490	2.145×104	SWCL250	34.7
SWC－Ⅰ75	0.058×10-4	SWC200	1.47	SWC550	6.335×104	SWCL285	106
SWC－Ⅰ90	0.048×10-3	SWC225	7.812	SWC620	0.13×106	SWCL315	356
SWC－Ⅰ100	0.26×10-3	SWC250	28.2	SWCZ700	0.32×106	SWCL350	938
SWC－Ⅰ120	0.26×10-2	SWC265	54.8	SWCZ750	0.75×106	SWCL390	2323
SWC－Ⅰ150	2.65×10-2	SWC285	82.8	SWCZ800	1.06×106
SWC－Ⅰ180	3.60×10-2	SWC315	279	SWCZ900	5.62×106
SWC－Ⅰ200	1.03	SWC350	744	SWCZ1060	30.3×106
SWC－Ⅰ225	1.89	SWC390	1860

4．When there are simultaneous horizontal andvertical angular misalignments on the universal jointshaft，the composite deflection angle is calculated using Formula (6)：

Where，β= Composite deflection angle，(°)；
β1= Horizontal deflection angle，(°)；
β2= Vertical deflection angle，(°)．

5．If the joint diameter of the shaft is 390mm or less，Formulas (7) and (8) should be used to check the maximum speed in addition to the considerations of torque and bearing life．

Where，nmax = Maximum operating speed，rpm；
[nβ] = Maximum permissible speed in relation to operating deflection angle，rpm．(See Figure 7-1)
[nL] = Maximum permissible speed in relation to operating length, rpm．(See Figure 7-2)

6．If the line speed of the shaft is over 7m/s, dynamic balancing test is requested, normally to a balancing accuracy between G16~G40. There are complex variables which effects the balancing grade. The customer's verification should be in a lower rank.