LOAD KING 35-127 M, Operator'S Manual

Page: 136 / 216

136
35-127 M
Maintenance
Hydraulic Hoses
The service life of a hose used on a mobile crane may significantly vary from the indicated lifetime of the
hose from the manufacturer� The service life is influenced by a number of factors such as environment
(temperature, humidity, corrosive air���) and use, duty cycles, bending cycles, abrasion, fluid etc� External
unfavorable factors like heat, repeated bending under pressure etc� can reduce the lifetime significantly
whereas other circumstances could allow a service life that may exceed a given period�
Inspection of Hydraulic Hoses
A daily visual check of the crane by the operator or a competent service person before starting operation
shall include an inspection of the hydraulic hoses as far as possible; any traces of hydraulic oil on the
crane or beneath a parked mobile crane shall lead to further investigation� The daily check might indicate
irregularities and / or leakages in the hydraulic system that should be taken care of immediately� In
addition to these daily checks,
Load King
recommends annual inspections of all hose assemblies as a
part of the maintenance of the crane� Older cranes may require more frequent inspections�
Inspection Criteria:
Hydraulic hoses should be replaced if any of the following criteria are true:
●
Damage on outside surface (cover) of the hose (e�g� crack, cuts, any abrasion that exposes the
hose braid (reinforcement)�
●
Embrittlement due to the aging of the outer surface (cracking appearing)�
●
Deformation that does not correspond to the original routing and shape of the hose� This criteria
shall be checked in both non-pressurized and pressurized conditions and / or when bending (e�g�
check for separation of hose layers, formation of blowholes, crushed points, kinks, torsioning)�
●
Leakage�
●
Damage or deformation of hose fittings (sealing functionality affected)�
●
Movement between hose bulk and hose assembly (e�g� hose creeping out of fitting)�
●
Corrosion on a fitting that can affect the strength or function of the fitting�