Question

A firm operates a flow shop building kitchen cabinetry for recreational vehicles. The major activities of this process are listed below.

Task	Duration (hours)	Predecessor 1	Predecessor 2	Predecessor 4
A	4	--
B	6	--
C	2	A
D	6	A
E	3	B	C
F	3	B	C
G	5	D	E	F
H	1	G

Draw the appropriate network for this project.

What would the cycle time be if the goal is to produce 20 units per month (the plant operates 160 hours per month)?

What is the theoretical minimum number of workstations needed?

Balance with the most following tasks heuristic. What tasks are assigned to which stations?

What is the efficiency of the line obtained in part d?

please write the the answer, no pic :)

Answer 1

Network:

.

Task	Duration (in hours)	Predecessors	ES	EF
A	4	none	0	4
B	6	none	0	6
C	2	A	4	6
D	6	A	4	10
E	3	B,C	6	9
F	3	B,C	6	9
G	5	D,E,F	10	15
H	1	G	15	16
Total cycle time	30	30

Task	Task followed
A	6
B	4
C	4
D	2
E	2
F	2
G	1
H	0

TCT	Total cycle time	30
TC	Target cycle time	8	160/20	Ans B
(TCT/TC)	Min Workstation	3.75	4	Ans C

Balancing:

Task	Time (in minutes)	Work station	IDLE TIME
A	4	1	4
B	6	2	2
C	2	2	0
D	6	3	2
E	3	1	1
F	3	4	5
G	5	4	0
H	1	1	0

TCT	Total cycle time	30
TC	Target cycle time	8	160/20	Ans B
(TCT/TC)	Min Workstation	3.75	4	Ans C
	Idle time	2	mins	Sum of spare
TCT/(6*8)	Efficiency of general cycle	62.50%	Theoretical	Ans D
TCT/(4*8)	Efficiency of general cycle	93.75%	Actual