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Overhaul of Fire Trucks

Overhaul of Ladder Trucks

Overhaul Overhaul of Ladder Trucks

Ladder Truck Overhaul Process

Disassembly of Ladder Trucks

Disassembly of a ladder truck is done by removing the ladder and its fixtures from the vehicle body. The removed ladder is further disassembled into sections and then measured for distortion, warp and deformation and checked for crack, damage and other defects to ensure safety of the ladder.

  • Example of deformed ladder
    Example of deformed ladder
  • Disassembling a ladder
    Disassembling a ladder

Repair of Cylinders

A ladder truck is in danger when its ladder cylinder loses functionality. Among the ladder truck components subject to overhaul, the cylinders are particularly important.

  • Re-plated cylinder rod
    Re-plated cylinder rod
  • Sliding damage in a cylinder
    Sliding damage in a cylinder

Replacement of Hydraulic Gear Pump

After a long time of use the gears and casing of the hydraulic pump may have wear and damage, leading to performance deterioration.

Worn/damaged gear
Worn/damaged gear
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Disassembly and Repair of Gyro Turntable

Damage in the gyro turntable may result in a major accident. Disassembly and repair of the turntable is one of the critical maintenance items during overhaul.

  • Damaged gyro turntable
    Damaged gyro turntable
  • Gyro turntable being repaired
    Gyro turntable being repaired

Disassembly and Repair of On-board Equipment

After 7 years of use, consumables including internal packing are found to have deteriorated due to wear and sliding parts are considerably damaged.

Damaged drive shaft
Damaged drive shaft
  • Disassembling equipment
    Disassembling equipment
  • Reassembling equipment
    Reassembling equipment
  • 4-way solenoid valve (before disassembly)
    4-way solenoid valve (before disassembly)
  • 4-way solenoid valve (after disassembly)
    4-way solenoid valve (after disassembly)
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Replacement of Wire Ropes and Hydraulic Hoses

  • Hydraulic hoses
    Hydraulic hoses
    Hydraulic rubber hoses deteriorate and get deformed due to aging. All rubber hoses should be replaced during overhaul.
  • Wire ropes
    Wire ropes
    Ladder trucks use wire ropes in two locations: the extension device and the lifter.

Guideline for Replacing Wire Ropes

  • Deformation
    Deformation
  • Damage
    Damage
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Maintenance of Control Computers and Sensors

Unlike the conventional ladder trucks, the new model ladder trucks are fully controlled by a computer. It is thus very important to maintain the computer and connected sensors in good condition.

  • Printed circuit board  examination
    Printed circuit board examination
  • Computer for ladder control
    Computer for ladder control

Change of Hydraulic oil

Most of hydraulic device/machinery malfunctions and increased power consumption are said to be caused by the use of deteriorated fluid. These problems may lead to breakage or even shutdown of the overall hydraulic system.

New and old return filter elements
New and old return filter elements

Appearance Inspection
The hydraulic oil is sampled from the top and bottom of the tank as well as the piping and then put in test tubes to be compared against new one in terms of color, odor and inclusion of foreign substances.

  • A. Brand new
  • B. Normal
  • C. Needs to be changed
  • D. Deteriorated
A. Brand new→ B. Normal→ C. Needs to be changed→ D. Deteriorated

Painting, Plating and Rigging

Primer repair (including sheet metal and patty) → Wash primer coating (pink) → Painting (red) → Finishing (red)

  • Primer coating
    Primer coating
  • Re-plating
    Re-plating
Fixing
Fixing

Internal Inspection and Examination

  • Test operation and internal inspection of ladder Equipment Inspection Institute
    Test operation and internal inspection of ladder
  • Examination commissioned by Japan Fire
    Examination commissioned by Japan Fire Equipment Inspection Institute
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