CH 7-Overtime Curves
July 21, 2022 | Author: Anonymous | Category: N/A
Short Description
Download CH 7-Overtime Curves...
Description
Ch 7
Overtime Curves Rate of slow down in Productivity due to Overtime Fatigue
Overtime Curves Productivit y Rate - 2hr over time load
100%
100% 95% 93%
y a d / e t a r n o i t c u d o r P
91%
89%
87%
85%
80%
83%
81%
80%
79% 79 %
79% 79 %
78%78%
60%
40%
0
2
4
6
8
10
12
14
Days
1
Ch 7
Overtime Curves Productivity Rate Rate - 4hr over time lo load ad 100%
100% 95% 93%
91%
88% 86% 83%
y a d / e t a R n o i t c u d o r P
81%
80%
78%
76% 73%
72% 70%
68%
60%
40% 0
2
4
6
Days
8
10
12
14
Overtime Curves
2
Ch 7
Overtime Curves Duration curve to reach zero added production in a 2hr O. O.T T work
x=0
y= b=
ax + b 125
x=14
out of
125
0.8
y=
100
14a= x= at 2 HR
y=
‐25
‐1.8
‐1.8
x +
125
At y=
100
1.8
x
=
25
x
=
14.0
Overtime Curves Duration curve to reach zero added production in a 2 hr O.T O.T work y‐axis 150% 125%
y = 100% 100%
y = 125% ‐ 1.8 x
50%
Prod day
(0,0)
2
4
6
8
10
12
14
16
18 18
20
x‐axis
3
Ch 7
Overtime Curves Duration curve to reach zero added production for 2hr O. O.T T work
Calculated days for zero additional production
x =
14.0
The average extra daily production
125 + 0
/2
days 12.5 %
Overtime Curves Duration curve to reach zero added production for 2hr O. O.T T work To impose a net additional production of 20%
120
Av y
At day 1
125
Max Y
Select
115
Min Y
Find x =
5.6
days
Calculate the days for this scenario
4
Ch 7
Overtime Curves Duration curve to reach zero added production in a 2hr O. O.T T work Decisions to be made
A
add few laborers, or
B
make OT shifts per each alternating crew, or
C
let all laborers work OT before they reach zero additional Production
Overtime Curves – – Plaster Example Given
Forecasted quantities of plaster Existing crews
4 crews x
62,000.00 ms 6 laborer
Average rate
3.00 $/hr
Normal working time
8.00 hr/day
To date total production
Required
24.00 Lab
42,000.00 ms
Number months incurred
4.00 mth
Av production rate / laborer /hr
1.95 ms/hr
Av Prod / mth 1‐GM asks for an increase of 40% production for the next coming month (4 weeks)
10,500.0 ms/mth 14,700.0
2‐ Extra OT cost rate is 1.25 3‐ avoid working times more than 2 hrs a day
5
Ch 7
Overtime Curves – – Plaster Example Scenario A
1‐ Use additional 12 laborer
Prod factor=
12 24.0
percent increase
50.00 %
deduct crowding impact 8%
Net Increase
42.00 %
2‐ No Overtime usage crews No 3‐ NO over Time factor
36.0 0%
Total percent increase
42.00 %
Total new Prod /lab/hr
2.77 ms
Total new Prod /mth/crews
14,910.0 ms
Remaining Production Needed
210 ms
Overtime Curves ‐ Plaster Example Cost A
Add laborer cost
day
rate/ hr
28 x 12
336
OT. OT. cost
day
OT.rate/ hr
add/1 lab
NA
NA
3.00
Add.Cost 8,064.00 Add.Cost
add/ x lab
Total Add Cost
8,064.00
6
Ch 7
Overtime Curves ‐ Plaster Example Scenario B
1‐ Use additional 4 laborers
Prod factor=
4 24.0
percent increase
16.67 %
2‐ Split the crew into 2 groups and use weekly alternating OT shifts
crews No
28.0
3‐ Use the curve of y = ‐1.8x + 125
x=7 y=
113 %
Av production
118.8 %
percent increase / week
18.8 %
percent increase / week /crew
9.4 %
Total percent increase
26.0 %
Total new Prod /lab/hr
2.46 ms
Total new Prod /mth/crews
13,234.4 ms
Remaining Production Needed
‐1,466 ms
Overtime Curves ‐ Plaster Example Cost B
Add laborer cost
day
rate/ hr
28 x 4
112
3
OT OT.. cost
day
OT.rate/ hr
Add.Cost 2,688.00 Add.Cost
28
0.75
add/1 lab
1
3.75
7.50
add/ 14 lab x 28 d
14
2.00
2,940.00
Total Add Cost
5,628.00
7
Ch 7
Overtime Curves ‐ Plaster Example Scenario C
1‐ Use the 0 laborers
Prod factor=
0 24
percent increase 0.00 2‐ Split the crew into 2 groups and use 2 days OT shifts alternating OT shifts crew No 24 3‐ Use the curve of y = ‐1.8x + 125 x=2 y= 121 Av production 123.2 percent increase / week 23.2 percent increase / week /crew 11.6 Total percent increase 11.6 Total new Prod /lab/hr
%
% % % % %
2.18 ms
Total new Prod /mth/crews Remaining Production Needed
11,718.8 ms ‐2,981 ms
Overtime Curves ‐ Plaster Example Cost C
Add laborer cost
OT. OT. cost
day
rate/ hr
Add.Cost
0
3
NA
day
OT.rate/ hr
Add.Cost
28
0.75
add/1 lab
1
3.75
7.50
add/ 12 lab x 28 d
12 12
2.00
2,520.00
Total Add Cost
2,520.00
8
Ch 7
Overtime Curves Decisions to be made Still you can come up with other scenarios and assess the optimal production increase rate and its cost impact. Note that sometimes GMs prefers to pay a penalty that is cheaper than involving additional OT rates and OT staff fees.
Overtime Curves Decisions to be made Scenario
% recovery
Total Add Cost
A ‐ Plaster
42
%
8,064.00
B ‐ Plaster
26
%
5,628.00
C ‐ Plaster
12
%
2,520.00
D ‐ Plaster (pay Penalty)
0
%
7,500.00
A ‐ Tiles
25
%
4,704.00
B ‐ Tiles
35
%
9,408.00
C ‐ Tiles
11
%
1,680.00
D‐ Tiles (pay Penalty)
0
%
5,000.00
9
Ch 7
Overtime Curves Decisions to be made YOU YO U ARE THE ONE TO MAKE A PROPER DECISION, AND NOT ANY COMPUTER SYSTEM
10
View more...
Comments
