Doosan D20S-5 Operation & Maintenance Manual page 132

inclines or poor surface conditions. inclines or poor su
Maintenance Section Maintenance Section
Inspection, Maintenance and Repair of Lift Truck Forks Inspection, Maintenance and Repair of Lift Truck Forks
The following section gives practical guidelines for The following section gives practical guidelines for
inspection, maintenance and repair of lift truck forks. inspection, maintenance and repair of
It also provides general information on the design It also provides general information on the design
and application of forks and the common cause of and application of forks and the common cause of
fork failures. fork failures.
Lift truck forks can be dangerously weakened by Lift truck forks can be dangerously weakened by
improper repair or modification. They can also be improper repair or modification. They can also be
damaged by the cumulative effects of age, abrasion, damaged by the cumulative effects of age, abr
corrosion, overloading and misuse. corrosion, overloading and misuse.
A fork failure during use can cause damage to the A fork failure during use can cause damage to the
equipment and the load. A fork failure can also equipment and the load. A fork failure can also
cause serious injury. cause serious injury.
A good fork inspection and maintenance program A good fork inspection and maintenance program
along with the proper application can be very along with the proper application can be very
effective in preventing sudden failures on the job. effective in preventing sudden failures on the job.
Repairs and modifications should be done only by Repairs and modifications should be done only by
the fork manufacturer or a qualified technician who the fork manufacturer or a qualified technician who
knows the material used and the required welding knows the material used and the required welding
and heat treatment process. and heat treatment process.
Users should evaluate the economics of returning Users should evaluate the economics of returning
the forks to the manufacturer for repairs or the forks to the manufacturer for repairs or
purchasing new forks. This will vary depending on purchasing new forks. This will vary depending on
many factors including the size and type of fork. many factors including the size and type of fork.
Forks should be properly sized to the weight and Forks should be properly sized to the weight and
length of the loads, and to the size of the machine length of the loads, and to the size of the machine
on which they are used. The general practice is to on which they are used. The general practice is to
use a fork size such that the combined rated use a fork size such that the combined rated
capacity of the number of forks used is equal to or capacity of the number of forks used is equal to or
greater than the "Standard (or rated) Capacity" of greater than the "Standard (or rated) Capacity" of
the lift truck. the lift truck.
The individual load rating, in most cases, will be The individual load rating, in most cases, will be
stamped on the fork in a readily visible area. This is stamped on the fork in a readily visible area. This is
generally on the top or side of the fork shank. generally on the top or
A fork rated at 1500 pounds at 24 inch load A fork rated at 1500 pounds at 24 inch load
 
center will be stamped 1500x24. center will be stamped 1500x24.
A fork rated at 2000 kg at 600 mm load center A fork rated at 2000 kg at 600 mm load center
 
will be stamped 2000x will be stamped 2000x600.
The manufacturer identification and year and date The manufacturer identification and year and date
of manufacture are also usually shown. of manufacture are also usually
rface conditions.
lift truck forks.
side of the fork shank.
600.
shown.
-129- -129-
Some countries have standards or regulations Some countries have standards or regulations
which apply specifically to the inspection and repair which apply specifically to the inspection and
of forks. of forks.
Users Users may may
Organization For Standardization-ISO Technical Organization For Standardization-ISO Technical
Report 5057- Inspection and Repair of Fork Arms Report 5057- Inspection and Repair of Fork Arms
and ISO Standard 2330 - Fork Arms - Technical and ISO Standard 2330 - Fork Arms - Technical
asion, Characteristics and Testing. Characteristics and Testing.
While there are no specific standards or regulations While there are no
in the United States, users should be familiar with in the United States, users should be familiar with
the requirements for inspection and maintenance of of the requirements for inspection and maintenance
lift trucks as provided by the 29 Code Federal lift trucks as provided by the 29 Code Federal
Register 1910.178 Powered Industrial Truck, and Register 1910.178 Powered Industrial Truck, and
ANSI/ASME ANSI/ASME Safety Standard(s) B56.1, B56.5 or Safety Standard(s) B56.1, B56.5 or
B56.6 as applicable to the type of machine(s) in B56.6 as applicable to the type of machine(s) in
use. use.
Environment Protection Environment Protection
When servicing this lift truck, use an authorized When servicing this lift truck, use an authorized
servicing area and an approved container to collect servicing area and an approved container to collect
coolant, oil, fuel, grease, electrolyte and any other coolant, oil, fuel, grease, electrolyte and any other
potential environmental pollutant before any lines, potential environmental pollutant before any lines,
fittings or related items are disconnected or fittings or related items are disconnected or
removed. removed. After After
materials in an authorized place and container. materials in an authorized place and container.
When cleaning the lift truck, be sure to use an When cleaning the lift truck, be sure to use an
authorized area. authorized area.
also also refer refer to to the the International International
specific standards or regulations
servicing, servicing, dispose dispose
repair
of of those those