R&M Materials Handling WIRE ROPE HOISTS Service - Manual (Page 126)

R&M Materials Handling, Inc.
4501 Gateway Boulevard
Springfield, Ohio 45502
P.: (937) 328-5100
FAX: (937) 325-5319
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R&M Materials Handling, Inc. reserves the right to alter or amend the above information without notice.
8.3.5 STEP 5: SWP% and remaining service life
SWP% and estimated remaining service life can be obtained from table below.
Hoist operating group marked on hoist's rating
plate
M4
(1Am)
M5
(2m)
M6
(3m)
M7
(4m)
Actual duration of service, S [h] SWP%
Estimated
remaining
service life
[years]
0 0 0 0 100% 10
80 160 320 630 90% 9
160 320 640 1260 80% 8
240 480 960 1890 70% 7
320 640 1280 2520 60% 6
400 800 1600 3150 50% 5
480 960 1920 3790 40% 4
560 1120 2240 4410 30% 3
640 1280 2560 5040 20% 2
720 1440 2880 5670 10% 1
800 1600 3200 6300 0% 0
When SWP% is zero, a General Overhaul (GO) must be conducted. Refer to section 'General Overhaul
(GO)'.
8.4 General Overhaul, GO
Once the SWP% of the hoist reaches zero, the hoist has exhausted its theoretical lifetime. The probability
of a defect in the hoist is therefore higher and operating safety is jeopardized. When the theoretical
lifetime is exhausted, a General Overhaul (GO) of the hoist must be conducted. Only the hoist
manufacturer or a service organization authorized by the hoist manufacturer may conduct a GO. The
components in the hoist that have an impact on hoist lifetime are inspected in a GO and critical
components are replaced. A new theoretical SWP is given to the hoist after completion of a GO.
!
When the Safe Working Period (SWP) of the hoist is exhausted, the hoist may only be used
after a GO has been conducted.
If the hoist is not provided with a condition monitoring unit, the end of the Safe Working Period must be
calculated in accordance with standard FEM 9.775, refer to section 'Calculation of the Safe Working
Period'.
8.5 Recommended tightening torques
Recommended tightening torques for screws and nuts in the hoist.
Tightening torque
Size Strength 8.8 Strength 10.9
[Nm] [Ft lb] [Nm] [Ft lb]
M4 2.7 2.0 4.0 2.9
M5 5.4 4.0 7.9 5.8
M6 9.3 6.8 14 10.3
M8 23 17.0 33 24
M10 45 33.0 66 48.5