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THERMAL CAPACITY

Since there is slippage within the flow charge during acceleration, 
heat is generated from friction. The thermal capacity of the 
FLEXIDYNE mechanism is based on balancing this heat 
generated during acceleration against the cooling time between 
accelerations. The amount of heat generated is determined 
by the amount of horsepower dissipated by slipping and the 
duration of each acceleration. If the flow charge weight is light, 
the heat generated will not be as great as that which would 
be generated with a heavier flow charge, when compared at 
the same acceleration time. A longer time between starts will 
dissipate more heat; therefore, higher starting horsepowers may 
be transmitted, or longer acceleration times may be allowable. 
(See Starting Cycle)

Acceleration times shown in Table 1 are for starting frequencies 
of one start per hour or less. If starting  frequency is more than 
once per hour, use acceleration time for actual starting cycle 
shown in Table 2.

Acceleration times listed in Tables 1 and 2 are the MAXIMUM 
permissible for the various starting frequencies listed. The 
MINIMUM acceleration time required for proper FLEXIDYNE 
mechanism operation is 1 to 1½ seconds. This is the time required 
for the flow charge to be uniformly distributed around the housing 
cavity before the unit "locks in". Any acceleration time between 
the minimum and maximum listed is acceptable, although a 
shorter acceleration time will generally provide longer wear life. 
For applications requiring a specific acceleration time (within 
these limits) flow charge may be added or removed to produce 
the required results.

Stalled

 — If a jam-up stalls the drive, the motor continues to 

run and the FLEXIDYNE mechanism slips. This causes heat to 
be generated at twice the rate of normal acceleration. Therefore, 
the allowable slipping time, when stalled, is half the allowable 
acceleration time given in Table 1.

Starting Cycle

 is the time from the beginning of one acceleration 

to the beginning of the next. Allowable acceleration times in Table 
2 are based on the assumption that the FLEXIDYNE mechanism 
will be running continuously except for a momentary stop before 
the next start. If the stop is more than momentary, decrease the 
actual starting cycle by one-half the stopped time before using 
Table 2; for example, with a 50 minute actual starting cycle of 
which 20 minutes is stopped time, decrease 50 by half of 20 to 
give 40 minutes as the starting cycle time to use for Table 2.

Grouped Starts

 — For several starts grouped together followed 

by uninterrupted running, add the acceleration times of all starts 
and consider it as the time for one start. The starting cycle would 
be the time from the beginning of one group of starts to the 
beginning of the next group.

Summary of Contents for FLEXIDYNE 70C

Page 1: ...ing without slip and with 100 efficiency Consequently the motor accelerates instantly to base speed while the load starts gradually and smoothly Housing Flow Charge Output Shaft Rotor Flexible Couplin...

Page 2: ...will be observed with greater amounts of flow charge The FLEXIDYNE mechanism should start the load smoothly and without delay provided the proper amount of flow charge has been used Should the accele...

Page 3: ...e housing cavity before the unit locks in Any acceleration time between the minimum and maximum listed is acceptable although a shorter acceleration time will generally provide longer wear life For ap...

Page 4: ...s Oz Lbs Oz 1 70C 70D 1 0 1 10 500 1 2 1 12 400 1 5 1 14 33 1 1 2 70C 70D 1 5 1 13 300 1 9 2 1 260 2 2 2 3 210 2 75C 75D 2 0 1 10 250 2 5 1 13 190 3 0 2 0 150 3 75C 75D 3 0 1 15 150 3 7 2 3 125 4 5 2...

Page 5: ...36 2 5 143 140 88 85 49 45 33 29 3 0 133 120 80 74 45 39 28 25 4 0 90 83 60 54 36 30 23 19 6 0 60 38 21 13 8 0 41 29 16 10 10 0 36 23 13 8 Starting HP Maximum Allowable Acceleration Time in Seconds Fo...

Page 6: ...and needle bearing inner race 7 Remove the six drive hub screws and remove the drive hub housing Remove housing seal 8 Remove rotor retainer and seal felt 9 Remove ball bearing snap ring and remove b...

Page 7: ...1 305138 411296 419007 407082 305018 419190 305091 305138 411296 419007 407082 305018 419190 305091 305138 411296 419007 407082 305018 419190 305091 305138 411296 419007 407082 305018 419190 30 32 34...

Page 8: ...tainless flow charge 3 Add flow charge Flexidyne Mechanism Doesn t Slip 1 Improper installation Output shaft jammed against housing 2 Flow charge in bearings causing bearing seizure 1 Readjust spacing...

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