- Operational planning:
-
Higher floor loading than provided for,
-
difficult handling of the additional test load,
- ban on carrying out any overload tests on-site in some fields of industry (e.g.
petrochemical plants).
- Operational safety:
- Anyone in the vicinity of the crane must be warned of the test procedure and
- must leave the area during the test.
Risk of accidents due to damage to load-bearing parts
After an overload test, carry out extensive investigations to ensure the intactness
of the load-bearing components.
Damage to load-bearing parts can occur due to cracks caused by overload and/or fatigue;
such defects are not exposed by an overload test. For this reason, an overload test can
give owners and operators a false sense of security.
To ensure the intactness of load-bearing components, extensive investigations are
recommended after an overload test and before carrying out hoist work. Such an
investigation consists of a visual inspection combined with function tests (including the
safety equipment) and can necessitate non-destructive inspections such as magnetic
particle or ultrasonic inspections.
Any malfunction or irregularity discovered during the inspection must be evaluated by an
expert. This person must determine whether the movement can be carried out safely or
whether immediate repair/modification is required.
Recommendations of Terex Cranes with Regard to Load Tests
Checking Assembly
Checking the correct crane assembly (e.g. after reconfiguration) must include:
- a visual inspection of all assembled parts on the ground before erecting the boom,
- a function check of the crane without or with limited load including:
• any movements important for the job
• an inspection of all limit switches (among others, the hoist limit switches),
- an inspection to ensure the assembly has been carried out in accordance with the
assembly instructions.
Load Test Factors
If load tests are required due to national laws for checking the assembly of the crane,
100% of the permitted load of the crane in the given configuration must not be exceeded.
Load tests due to national laws can be e. g. required
T300-1_T500-1_T780
Inspection
154 P/N 12261-683
REVISED: January 2015
To Next Page
Loading...
