Chapter 3

In a batch machining operation, setup time is 1.5 hours and batch size is 80 units. The cycle time consists of part handling time of 30 sec and processing time of 1.37 min. One part is produced each cycle. Tool changes must be performed every 10 parts and this takes 2.0 min. Determine (a) average cycle time, (b) time to complete the batch, and (c) average production rate.

Solve for :

a: Cycle time = ? minutes

b: Batch Time = ? per hour

c: Average Production Time: ? Minutes/piece

Typical cycle time for a production operation: T_c = T_o + T_h + T_th

where T_c = cycle time,

T_o = processing time for the operation

T_h = handling time (e.g., loading and unloading the production machine)

T_th = tool handling time (e.g., time to change tools)

Batch production: batch time T_b = T_su + QT_c

Average production time per work unit T_p = T_b/Q

T_su = setup time

Production rate R_p = 1/T_p

Job shop production: For Q = 1, Tp = T_su + T_c (Q=80 units)

For quantity high production: R_p = R_c = 60/T_p

For flow line production : T_c = T_r + Max T_o and R_c = 60/T_c

Group of answer choices

a=2.07 minutes b= 4.26 hrs c= 3.2 min/piece

a=2.07 minutes b= 4.26 hrs c= 4.0 min/piece

a=2.07 minutes b= 4.75 hrs c= 3.2 min/piece

None of the above