Tuesday, August 27, 2013

Types & Fundamentals: Parts -> Attachments

Attachments
Slipsheet attachment eliminates need for pallets.
Figure 2. Slipsheet attachment eliminates need for pallets.

Side-shifter controls enable the forks to be moved right and left.
Figure 3. Side-shifter controls enable the forks to be moved right and left.

Forklift equipped with a barrel clamp attachment.
Figure 4. Forklift equipped with a barrel clamp attachment.

Reach stacker used in marine terminals and longshoring.
Figure 5. Reach stacker used in marine terminals and longshoring.

Data plate for an attachment (sideshifter).
Figure 6. Data plate for an attachment (sideshifter).
Some common attachments are:
  • Slipsheet attachments which avoid the use of pallets. (Figure 2)
     
  • Sideshifters shift the forks right and left. (Figure 3)
     
  • Container handlers designed to lift shipping containers.
     
  • Carton clamps equipped with a pressure valve to squeeze the load.
     
  • Cotton or pulp bale clamps that grab and hold bales.
     
  • Paper roll handlers.
     
  • Barrel clamps. (Figure 4)
     
  • Rotators that grab and rotate the load.
     
  • Extending or telescoping forks such as in reach and turret trucks. (Figure 5)
     
  • Personnel platforms specially designed for lifting personnel.
Operators must be trained in the proper use of attachments because they alter the performance of the forklift. Attachments affect the truck's performance by changing its center of gravity, visibility, and capacity.

Potential Hazards:
  • Overloading. The weight of the attachment reduces the lifting capacity of the truck.
     
  • Tipover and falling loads. The attachment increases the load center by moving the load further away from the balance or fulcrum point.
Requirements:
  • Train operators in the fork and attachment adaptation, operation, and use limitations. [29 CFR 1910.178(l)(3)(i)(G)]
     
  • Retrain an operator if a new attachment is added to the forklift. Consult the operator's manual for instructions on how to use the new equipment.

  • Do not exceed the rated capacity of the forklift/attachment combination.
     
  • Know the mechanical limitations of your forklift.
     
  • Change capacity, operation, and maintenance instruction plates, tags, or decals when a forklift truck is equipped with an attachment.
     
  • Treat an unloaded forklift with an attachment as partially loaded. [29 CFR 1910.178(o)(4)]

  • Include attachments in a scheduled maintenance and inspection program. Tailor inspection steps to the attachment.

    • Examine load-bearing components for deformation.

    • Examine load-bearing welds for cracks.

    • Inspect mechanical and hydraulic components and maintain in accordance with the manufacturer’s instructions.
  • If the truck is equipped with front-end attachments other than factory installed attachments, request the truck be marked to identify the attachments and show the approximate weight of the truck and attachment combination at maximum elevation with load laterally centered. [29 CFR 1910.178(a)(5)]
     
  • Modifications or additions that affect capacity or safe operation shall not be performed without prior written approval from the forklift truck manufacturer. Capacity, operation, and maintenance instruction plates, tags, or decals shall be changed accordingly. [29 CFR 1910.178(a)(4)]

    • If no response or a negative response is received from the manufacturer, written approval of the modification/addition from a qualified registered professional engineer is acceptable. A qualified registered professional engineer must perform a safety analysis and address any safety or structural issues contained in the manufacturer’s negative response before granting approval. The forklift nameplates must be changed accordingly.

    • See Forklifts: Free Rigging Requires Manufacturer's Approval, OSHA Standard Interpretation, (1999, October 22). Free rigging is the direct attachment to or placement of rigging equipment (slings, shackles, rings, etc.) onto the forks of a powered industrial truck for a below-the-forks lift. This type of lift does not use an approved lifting attachment. Although free rigging is a common practice, it could affect the capacity and safe operation of a powered industrial truck.

Friday, August 23, 2013

Types & Fundamentals: Parts-> Forks

The forks (also known as tines or blades) carry the load. They have a heel where they curve upward and an upright shank where they are attached to the carriage.

Forks
Damaged fork.
Figure 2. Damaged fork.
Potential Hazards:

A fork that shows any of the following defects shall be withdrawn from service and discarded or properly repaired:
  • Surface cracks.
     
  • Blade or shank are not straight.
     
  • Fork angle from blade to shank is not straight.
     
  • Difference in height of fork tips.
     
  • Positioning lock not in working order.
     
  • Fork blade or shank wear.
     
  • Fork hooks wear.
     
  • Fork marking not legible.
Requirements and Recommended Practices:
  • Do not operate the forklift if the forks show any of the defects listed above.
     
  • Always inspect forks during the pre-operation inspection. Repair or replace the forks if they are not in good working order. Replacement parts shall be equivalent as to safety with those used in the original design. [29 CFR 1910.178(q)(5)]
     
  • Do not operate a forklift from which the positioning lock has been removed or is inoperable. As the forklift travels, the positioning lock holds the forks in position and prevents sliding of the forks and loss of the load.
Additional Information:

Tuesday, August 13, 2013

Types & Fundamentals: Parts -> Mast Types

Mast Types
There are a number of mast types:
SIMPLEX:

The features of a simplex mast are:
  • Single stage mast.
     
  • Limited Free Lift (4-6") Free lift is the distance the forks go up before the mast is extended.
     
  • Recommended Use: In loading and unloading trucks and in areas where overhead clearance is a problem.
DUPLEX:

The features of a duplex mast are:
  • Two stage mast.
     
  • Has greater Free Lift (50-60") than the simplex mast.
     
  • Can load and unload higher-tiered stacks than simplex.
Triplex mast in narrow aisle rider reach truck. Note that the forklift is removing stock from a rack. Foot and truck traffic in the opposite aisle way should be controlled to prevent injury from falling materials.
Figure 2. Triplex mast in narrow aisle rider reach truck. Note that the forklift is removing stock from a rack. Foot and truck traffic in the opposite aisle way should be controlled to prevent injury from falling materials.
TRIPLEX:

The features of a triplex mast are:
  • Three stage mast.
     
  • Has same Free Lift (50-60") as duplex mast but extends further.
     
  • Can load and unload higher-tiered stacks than simplex or duplex.
 
QUAD:

The features of a quad mast are:
  • Four stage mast.
     
  • Has same Free Lift (50-60") as duplex or triplex mast but extends further.
     
  • Can load and unload higher-tiered stocks than the duplex or triplex, but requires precautions at its highest lifting heights.
Note: The lifting capacity of the forklift decreases as its load is raised. For more information, see Load Handling and Narrow Aisles.




Visibility
Mast configuration can affect the operator's visibility. Newer mast designs, such as those that use two side cylinders, can provide substantially improved visibility compared with some older mast designs that have a single central cylinder. (Figures 3 and 4)

The operator should travel with the load trailing and/or use a spotter whenever necessary to achieve adequate visibility.
 
Mast with central cylinder obscuring visibility.
Figure 3. Mast with central cylinder
obscuring visibility.
High visibility mast with hydraulic cylinders on the sides.
Figure 4. High visibility mast with
hydraulic cylinders on the sides.

Tuesday, August 6, 2013

Types & Fundamentals: Parts

Types & Fundamentals: Parts

Basic Parts of a Forklift
As we continue our look at these very useful but potentially lethal powered industrial trucks (PIT), we will take an in-depth look at the various parts.

The following are the major parts of a forklift. This discussion focuses on the most common types of forklifts. Be sure to read the operator's manual for your forklift and follow the manufacturer's recommendations.
  • Mast and Carriage
  • Forks
  • Attachments
  • Nameplate
  • Danger, Warning and Caution Labels
  • Controls
  • Instruments
  • Battery
  • Overhead Guard
  • Tires
  • Other Safety and Warning Devices

Thursday, August 1, 2013

Types & Fundamentals Part 14: Power Sources

Hydrogen Gas


Flammable hydrogen gas is always present during battery recharging. Hydrogen gas is potentially explosive if allowed to accumulate in a closed area.

Potential Hazards:
  • Ignition/explosion of accumulated hydrogen gas.
Requirements and Recommended Practice:
  • Post no smoking signs.
     
  • Use non-sparking tools.
     
  • Prevent open flames, sparks, or electrical arcs in the battery charging area to minimize the danger of explosion.
     
  • Provide adequate ventilation.
     
  • Open the battery cover when charging, so that the hydrogen gas can vent better. This is especially important in confined areas where the danger of accumulation is greatest.