2. Lifting rigging Precautions
• 1 weight lifting spreader material shall not exceed the
working load limit before using the spreader used visual
inspection and check their working load limit based on load
lifting spreader before use to meet the requirements .
• 2 spreader is not allowed to repair or re-processing (
welding , heating, heat treatment, surface chemical
treatment ) , mobile crane 500 ton as described above must
be handled , should be returned to the original
manufacturer or under the expert guidance of the original
manufacturer .
• 3 When lifting heavy objects , beneath the weight strictly
prohibited.
3. Lifting point mechanical coupling
component overhaul
• Mainly used to connect coaxial coupling or substantially parallel to the two axis , torque is transmitted . On the crane motor torque transmitted
through the gear unit and coupling to the low speed shaft to complete the load lifting , big, car running , etc., on a multi-purpose crane gear
couplings, flexible pin coupling not commonly used , because installation accuracy , anchor bolts loosening and bridge deformation, poor lubrication
and other reasons the tooth wear. Therefore, to carry out regular checks to deal with the coupling .
•
• ( 1 ) The basic requirements for inspection of the coupling : coupling connections firmly , bolts and keys are not allowed to connect loose coupling
rotating radial runout and runout , when there should be a clear visual observation feeling, when measured by the instrument , can not exceed the
limit.
•
• Security checks ( 2 ) Gear couplings : transmission gear coupling noise increases occurred or equipment overhaul should open inspection , the focus
check the following:
•
• ① shaft coupling bolt holes badly worn , the agency will start beating occurred , and even cut off the bolt , so the bolt holes badly worn and can not
be repaired should be scrapped.
• ② tooth wear thick 15% -20 % more than the original tooth thickness should be scrapped . Lifting bodies and non- equilibrium luffing mechanism was
15% , 20% other agencies .
• ③ flat keyway wear , the key to loosening , monorail cranes or even fall off . Primary keyway in the shaft rotated 90 ° or 180 ° position, the re-
opening a new keyway or key plus the thickness of not more than 15% of the cushion pad. Welding allowed keyway , keyway hoisting mechanism
allowed for repair.
• When any part of the coupling ④ cracks should be scrapped , have broken teeth should be scrapped.
•
• ( 3 ) Flexible Couplings check: flexible pin coupling rubber ring or leather pad when damaged, should be replaced , if the dowel pin hole and pushed a
bad vibration, rotation angle should be half re- drilling replace the standard new studs are not allowed to expand with the original ones dowel pin
holes .
• ( 4 ) with a lubricating device for coupling seal is intact , oil is bad, if there is oil leakage leakage. The problems mentioned above , you should replace
the seal or lubricating oil, lubricating oil should replenish missing .
4. Common causes of damage hook
lifting machinery group analysis
• Hook set is in use, from the loss of the ring in the form of appearance can be seen, often wear mouth parts hook
and pulley rim broken.
•
• Wear hook mouth parts as a normal phenomenon , mainly when the heavy lifting to be bound to adjust the focus
of their own , forcing the child or wire rope sling hook sliding wear in the mouth .
•
• Wheel rim broken, mainly caused by the collision , because the group did not rise to the necessary hook height ,
the car was pulled oblique instability or hanging crooked , heavy line and hook produced a strong swing to the
other objects in the pulley collision the cause ; there drivers violate the rules, do not check up from the limit
switch , the starting pay no attention to hook up the situation , causing the hook , " heaven ", so that the pulley
damage ring .
•
• Risk hardly occurs in the hook block , the sipes are often empty at the end of the threaded bore or a threaded rod
portion between the tail hook , and cracks due to stress concentration . Maintenance should remove the hook nut
, clean the top of the dirt, carefully check . Hook should always check whether the nuts and bolts hook , materials
lifting equipment or parts of other connections are loose or off the case , to prevent the hook off on their own .
You should also check for corrosion tail hook threaded nut for each hook , smear grease if necessary.
•
• Insulation pad insulation on the hook set , insulating sleeve etc. not broken , you should always check , and
remove dust, moisture should be dried immediately after . Should report regularly to the lubrication points and
grease hinge point , the thrust bearing at the bottom of the hook nut to regularly refuel.
