Imagine you've just climbed inside the cab of your telehandler. A hulking load of concrete blocks sits on the dusty path in front of you. Your mission, should you choose to accept it, is to lift and place that load up to the second story of the structure your crew is building. What do you do?
First things first: consult your load chart.
Typically found inside the operator's compartment of a telehandler, load charts contain the vital information you need to lift and place material safely. They tell you how high you can lift and extend a certain weight without tipping the machine and endangering the lives of those around you.
Potentially confusing and difficult to decipher, load charts aren't much help if you don't know how to read them. But with a little bit of studying, anyone can learn to understand the load charts. In fact, understanding load charts is included in the forklift operator training course required in the United Statesby OSHA.
Take this typical load chart on the next page, for example. The scale on the left indicates height in feet above the ground level. The scale on the bottom shows the distance in feet out from the front tire of the machine. The arc lines represent the distance the boom is extended from the unit. Noted by the numbers 1 through 5, these arcs correspond with the position-extension markers on the operator side of the boom.
Load charts are developed using the ANSI/ASME B56.6 Safety Standard, which governs the design of rough-terrain forklifts. The weight or load shown on the chart assumes a 24-inch load center as defined by the B56.6 standard. This means that the load has a center of gravity that is 24 inches from the front of the carriage. Note that the standard is referenced at the bottom of the load chart. Telehandlers designed for the European market use a 20-inch load center, and as a result may list up to 20-percent more load capacity. Be sure to look for the standard for which the load chart was designed.
So, let's assume that your telehandler is equipped with a standard carriage and attachment tool, and that you do not plan to use outriggers. You want to raise that 3,000-pound load of concrete block 20 feet high, and you can only get to within 15 feet of the building. Referring to this load chart, can you accomplish your assigned task?
Because you will need to extend the boom 15 feet, you need to start at the 15-foot mark on the horizontal axis. By projecting up from that mark to intersect a line at the 20-foot mark on the vertical axis, the height to which you want to lift the load, you can see that the load will be in the 4,000-pound zone. That means you will be able to lift and place your 3,000 pounds of concrete blocks to the second story without exceeding the lifting capacity and stability of the machine.
You will need to monitor the position-extension markers on the boom as you are placing the load. Notice that the arc reference number 3 is on the edge of the 4,000-pound zone when the load is 0 to 12 feet off the ground. As the load is raised from 12 feet to 20 feet, the arc reference number is 3.5.
A telehandler load chart is 2-D and is designed assuming a load center that is 24 inches in front of the fork carriage back-rest and on the center line of the machine. If the weight of the load is off center — for instance, you are lifting a long pipe or trusses that aren't centered on the forks or scaffolding wider than 4 feet — the load center will shift and the load chart will no longer be accurate for lifting that specific load.
In this situation you should try to adjust the load to move its load center to 24 inches in front of the fork carriage and centered along the centerline. You can also look at fork extensions for large bulky loads that don't fit on standard forks. In addition you can adjust the distance between the forks. If you believe your load center is greater than 24 inches, you can then add the extra distance to the horizontal axis of the load chart. Compare this load with the actual load to determine if it can be lifted safely. In all situations, once you pick up the load, check the inclinometer in the canopy or cab. If the inclinometer is not at zero degrees, use the frame leveling feature of the machine until the inclinometer reads zero. This centers the machine's weight and the weight of the load along the centerline of the machine.
Keep in mind that the proper load chart will change depending on the attachment being used. Different fork carriages, such as those designed for masons, framers, and log and pipe applications, generally have different weight capacities. There are also job-specific attachments, such as truss booms and jib booms with and without winches, which come with their own load charts.
A telehandler is primarily intended for use as a material handler, but it can also be equipped with a personnel work platform, if approved by the manufacturer, and if the platform complies with the requirements of ANSI/ASME B56.6 - 2002, Section 8.24, "Platforms for Elevating Personnel." When using a personnel platform, you must keep in mind that the combined weight of the platform, personnel, tools, and load must not exceed one-third of the material-handling capacity of the telehandler.
Remember, safety should always be at the forefront of any construction job, and by learning to use load charts properly for each type of lifting task, your telehandler will continue to be a safe and productive tool for your job site.