Manitowoc National Crane NBT30H-2, Руководство по обслуживанию

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National Crane
03-20-2019 Control # 613-06
1-11
NBT30H-2 SERVICE MANUAL INTRODUCTION
1
10
Electrical System
Harnesses, Wires, and Connectors
Visually inspect all electrical harnesses, cables, and
connectors every month or 250 hours for the following:
• Damaged, cut, blistered, or cracked insulation.
• Exposed bare wires.
• Kinked or crushed wires and cables.
• Cracked or corroded connectors, battery terminals, and
ground connections.
If any the above conditions exist, evaluate, clean and replace
as necessary.
The climate in which the crane operates affects the service
life of the electrical components. The climate zones are
defined in Figure 1-1. Recommended replacement of
harness and cables is as follows:
• Climate zone C after 10,000 hours of service.
• Climate zones A and B with high ambient temperatures
and duty cycles after 8000 hours of service.
• Climate zones D and E after 5,000 hours of service.
• Salt water conditions after 8,000 hours of service.
Fatigue of Welded Structures
Experience has shown that highly stressed welded
structures when repeatedly subjected to varying stresses
caused by twisting, shock, bending, and intentional and/or
unintentional overloads, often become subject to weld
cracking which may be attributed to fatigue of the welded
joint. This condition is not uncommon in construction
equipment.
Equipment should be periodically inspected for evidence of
weld fatigue. The frequency of these inspections should
increase with the age of the equipment and the severity of
the application.The following are known high stress areas
applicable to National Cranes, and a visual inspection of
these areas should be made part of an owner’s planned
preventive maintenance program:
• Telescopic Boom: wear pad retaining structures,
hydraulic cylinder attaching points, boom pivot shaft
retaining structures.
• Outrigger pads, beams, boxes and attachment
structures.
• Main frame: generally in the area of doubler plates and
crossmembers; at the junction of front and rear frame
members on truck cranes.
• Turntable bearing connection—where bearing is welded
to the crane superstructure or chassis.
• Counterweight support structures.
• Chassis axle and suspension mounting structures.
• Hydraulic cylinder end connections.
The above is provided only as a guide, and your inspection
plan should not be limited to the areas listed. A thorough
visual inspection of all weldments is good practice.
Anyone requiring more detailed inspection instructions and/
or repair procedures may request same by contacting your
local National Crane distributor.
Loctite
Always follow the directions on the Loctite container, as not
all Loctite types are suitable for all applications.Various types
of Loctite are specified throughout the Service Manual. The
following types of Loctite brand adhesives are available from
the Parts Department of the local National Crane distributor.
Application of Medium Strength Loctite®
NOTE: The fastener may be re-used; the adhesive may be
re-applied over cured adhesive residue.
The following procedure covers the proper application and
curing method for medium strength Loctite® adhesive/
sealant (Loctite® #243).
NOTE: Ensure the threaded surface, both male and
female, is clean of contaminants and free of dirt
and oil.
CAUTION
Skin and/or Eye Hazard!
Loctite type adhesives contain chemicals that may be
harmful if misused. Read and follow the instructions on
the container.
!