Maintenance overview
5.4 Measures required for winch monitoring
5 - 26 3 302 577 en Maintenance manual
GMK7450
16.08.2018
5.4.3 Example
A GMK7450 is equipped with a separate operating hours counter for the
hoist and is classified by Manitowoc Crane Group Germany GmbH as fol-
lows:
The used proportion S of theoretical service life is calculated based on the
individual inspection intervals as follo
ws:
1st Inspection
(1st year)
The truck crane was used for assembly work during the previous year: Load
sp
ectrum L 1, i.e. Km
1
= 0.125.
The operating hours counter for the main hoist reads 160 h, i.e. T1 = 160 h.
The used proportion S
1
of theoretical service life after the first inspection
therefore is: Inspection:
Remaining theoretical service life:
D1 = 3,200 h -160 h = 3,040 h.
The aforementioned values are entered in the table (see table example
p. 5 - 28).
2nd inspection (2nd year)
The truck crane was used for unloading work on docks: Load spectrum:
L 3, i.e. Km
2
= 0.5.
The operating hours counter for the main hoist reads 640 h, i.e. during this
period: 640 hrs. - 160 hrs. = 480
hrs. (160 hrs. were used during the first year)
T2 = 480 hrs.
Power unit group: M 3
Load spectrum: light L1, Km = 0.125
Theoretical service life: D = 3,200 h
S
i
0,125
0,125
---------------
160 h× 160 h==