SAFETY NOTICE 6/88
The
Department has now completed its review of the results obtained from the study
(conducted during 1986/87 with the assistance of the industry) to examine the
deterioration in the strength of inservice crane wire rope. The following
recommendations should be considered:
1.
The
study showed that the records for wire rope installed on cranes were, in many
cases, unsatisfactory and incomplete. Owners and operators are therefore
requested to review the systems currently employed to ensure that accurate date
is maintained including:-
a.
copy
of the original wire rope Test Certificate,
b.
date
fitted to crane clearly identifying particular crane,
c.
record
of any cutting and slipping,
d.
record
of lubrication (type, frequency, etc.)
2.
The
wire rope lubrication frequency and application procedure should also be
reviewed; it was found that 20% of the wire rope samples examined had received
inadequate lubrication.
3.
Owners
and operators are requested to review their crane rope renewal/maintenance
policies: the Department would recommend that the following approach be
adopted:-
a.
for
cranes known to be in frequent use rope should be routinely renewed on an
annual basis. (More frequent replacement may be necessary in some cases.)
b.
for
cranes known to be operated less frequently, where corrosion is likely to be
the dominant mechanism in any deterioration that may occur, it is recommended
that spare ropes be maintained so that all ropes may be changed on an annual
basis. The rope removed from service should then be sent onshore for cleaning,
inspection and, if fit for further use, lubrication (the lubrication should be
carried out using a suitable system which ensures full penetration) prior to
being returned for further service. Consideration should be given to the
application of storage lubricants, as distinct from service lubricants, where
appropriate.
4.
Investigations
into recent crane rope failures have identified a need for regular cutting and
slipping of inservice wire rope (particularly on cranes used less frequently)
to remove the “dead end” section. This section appears to be particularly
vulnerable to corrosion due to its exposed position and inaccessibility for
effective dressing techniques.
5.
Any
queries regarding this Safety Notice should be addressed to Mr T Kimber,
Principal Mechanical Inspector, at the address below (Tel. 01-211-3822)
N G
Marguerie
Head of
Inspection and Operations Branch
Department
of Energy
Petroleum
Engineering Division
Thames
House South
Millbank
LONDON SW1P
4QJ