Doosan D20G, Service Manual

Page: 1136 / 1209

Maintenance Section
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Inspection, Maintenance and Repair of Lift Truck Forks
The following section gives practical guidelines for
inspection, maintenance and repair of lift truck forks.
It also provides general information on the design
and application of forks and the common cause of
fork failures.
Lift truck forks can be dangerously weakened by
improper repair or modification. They can also be
damaged by the cumulative effects of age, abrasion,
corrosion, overloading and misuse.
A fork failure during use can cause damage to the
equipment and the load. A fork failure can also
cause serious injury.
A good fork inspection and maintenance program
along with the proper application can be very
effective in preventing sudden failures on the job.
Repairs and modifications should be done only by
the fork manufacturer or a qualified technician who
knows the material used and the required welding
and heat treatment process.
Users should evaluate the economics of returning
the forks to the manufacturer for repairs or
purchasing new forks. This will vary depending on
many factors including the size and type of fork.
Forks should be properly sized to the weight and
length of the loads, and to the size of the machine on
which they are used. The general practice is to use a
fork size such that the combined rated capacity of
the number of forks used is equal to or greater than
the “Standard (or rated) Capacity” of the lift truck.
The individual load rating, in most cases, will be
stamped on the fork in a readily visible area. This is
generally on the top or side of the fork shank.
y
A fork rated at 1500 pounds at 24 inch load
center will be stamped 1500x24.
y
A fork rated at 2000 kg at 600 mm load center
will be stamped 2000x600.
The manufacturer identification and year and date of
manufacture are also usually shown.
Some countries have standards or regulations which
apply specifically to the inspection and repair of
forks.
Users may also refer to the International
Organization For Standardization-ISO Technical
Report 5057- Inspection and Repair of Fork Arms
and ISO Standard 2330 - Fork Arms - Technical
Characteristics and Testing.
While there are no specific standards or regulations
in the United States, users should be familiar with
the requirements for inspection and maintenance of
lift trucks as provided by the 29 Code Federal
Register 1910.178 Powered Industrial Truck, and
ANSI/ASME Safety Standard(s) B56.1, B56.5 or
B56.6 as applicable to the type of machine(s) in use.
Environment Protection
When servicing this lift truck, use an authorized
servicing area and an approved container to collect
coolant, oil, fuel, grease, electrolyte and any other
potential environmental pollutant before any lines,
fittings or related items are disconnected or removed.
After servicing, dispose of those materials in an
authorized place and container. When cleaning the
lift truck, be sure to use an authorized area.