BEAM CLAMPS

Steelworkers are required to move and handle many steel beams and steel shapes. When off-loading steel from vehicles and storing for further use, beam clamps are much more practical than using slings or chokers, especially when the flanges are the only available parts of the load. Figure 6-30 shows three different types of beam clamps. View A shows a clamp designed for use on a beam with a flat flange, either an I or an H. The clamp in view B may be used on beams with a circular cross-sectional area or where only one side of the flange is accessible. View C shows a clamp that is useful for connection to a column with a snatch block attached. The clamps shown can all be fabricated in the shop or field.

Hooks, shackles, and beam clamps must have the rated capacities and SWL permanently stenciled or stamped on them. OSHA identification tags can be acquired at no cost from COMTHIRDNCB DET, Port Hueneme, California, or COMSECONDNCB DET, Gulfport, Mississippi. Metal dog tags are authorized providing the required information is stamped onto the tags.

OTHER LIFTING EQUIPMENT

Other devices used for moving equipment are as follows: spreader bars, pallets, jacks, planks and rollers, blocks and cribbing, and scaffolds.

SPREADER BARS

In hoisting with slings, spreader bars are used to prevent crushing and damaging the load. Spreader bars are short bars, or pipes, with eyes fastened to each end. By setting spreader bars in the sling legs above the top of the load (fig. 6-31), you change the angle of the sling leg and avoid crushing the load, particularly in the upper portion.

Spreader bars are also used in lifting long or oversized objects to control the sling angle, as shown in figure 6-32. When spreader bars are used, make sure you do not overload the end connection. A spreader bar has a rated capacity that is the same as hooks and shackles. A good rule of thumb is the thickness of the spreaders end connection should be the same as the thickness of the shackle pin.

PALLETS

Cargo pallets coupled with slings are an immense advantage on jobs that involve moving a lot of small items (fig. 6-33). Spreader bars can be used often to avoid damaging the pallet and the load. The pallet supplies a small platform on which a number of items can be placed and then moved as a whole instead of piece by piece. Palletizing is clearly easier and faster than moving each item by itself.

Commonly, packages of the same size are palletized together, and when shipped, remain on the pallet until they are used up. You may not have the luxury of having excess pallets at your job site;

Figure 6-31.-Using spreader bars.

Figure 6-32.-Spreader bar used with an oversized load.

however, you need to have several to work efficiently. One can be loaded as the prior loaded one is being lifted. After each pallet is unloaded, the hoist will return for reloading. With two pallets, you are able to maintain a steady flow of material. One set of slings will be able to handle any number of pallets.

JACKS

To be able to place cribbing, skids, and rollers, you need to be able lift a load a short distance. Jacks are designed and built for this purpose. Jacks are also used for precise placement of heavy loads, such as beams, or for raising and lowering heavy loads a short distance. There are a number of different styles of jacks available; however, only heavy-duty hydraulic jacks or screw jacks should be used. The number of jacks used is determined by the weight of the load and the rated capacity of the jacks. Ensure the jacks have a solid footing and are not susceptible to slipping.

Jacks are available in capacities from 5 to 100 tons. Small capacity jacks are normally operated through a rack bar or screw, and large capacity jacks are usually operated hydraulically (fig. 6-34).

The types of jacks used by Steelworkers are as follows:

1. Ratchet lever jacks are rack bar jacks having a rated capacity of 15 tons. These jacks have a foot lift by which loads close to the base of the jack can be engaged (fig. 6-34, view A).

2. Steamboat ratchets (often referred to as pushing and pulling jacks) are ratchet screw jacks of 10-ton-rated capacity with end fittings that permit pulling parts together or pulling them apart. They are primarily used for tightening lines or lashings and for spreading or bracing parts in bridge construction (fig. 6-34, view B).

3. Screw jacks have a rated capacity of 12 tons. They are approximately 13 inches high when closed and have a safe rise of 7 inches. These jacks are used for general purposes, including steel erection (fig. 6-34, view C).

Figure 6-35.-Use of planks and rollers.

4. Hydraulic jacks are available in many different capacities and are used for general purposes (fig. 6-34, view D).

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