Environmental Engineering Reference
In-Depth Information
20
W/
2). For the revised example, we will also assume that the worker is now
required to twist 90 degrees when placing the object on the packing station. We
will also assume the object has good couplings.
RWL
+
LC
(
HM
)(
VM
)(
DM
)(
AM
)(
FM
)(
CM
)
The LC (load constant) has been defined as 23 kg, or 51 lb.
Tables 2.7 to 2.12 are multiplier tables for the revised lifting equation (see
Waters et al. 1994), and can be used to evaluate these equations:
H
=
=
20
+
25
/
2
=
32
.
5cm
;
HM
=
0
.
78
V
=
70
;
VM
=
0
.
99
D
=
5cm
;
for
D<
25 cm
,
set
D
=
25
;
DM
=
1
.
00
90
◦
A
=
;
AM
=
0
.
71
F
=
4 lifts
/
min
;
≤
≤
;
=
0
.
72
1 hour
duration
2 hours
FM
;
=
1
.
0
Coupling is “good”
CM
9
.
08 kg
Recall from the example using the 1981 guide that AL was calculated to
be 14.25 kg. If we were to discount the asymmetry factor, the RWL would be
12.8 kg, which is close to the AL value of 14.3 kg.
Therefore, the RWL
=
23
(
0
.
78
)(
0
.
99
)(
1
.
00
)(
0
.
71
)(
0
.
72
)(
1
.
00
)
=
Ta b l e 2 . 7
Horizontal Multiplier
H
(in.)
HM
H
(cm)
HM
<
10
1.00
<
25
1.00
11
0.91
28
0.89
12
0.83
30
0.83
13
0.77
32
0.78
14
0.71
34
0.74
15
0.67
36
0.69
16
0.63
38
0.66
17
0.59
40
0.63
18
0.56
42
0.60
19
0.53
44
0.57
20
0.50
46
0.54
21
0.48
48
0.52
22
0.46
50
0.50
23
0.44
52
0.48
24
0.42
54
0.46
25
0.40
56
0.45
>
25
0.00
58
0.43
60
0.42
63
0.40
>
63
0.00
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