Precast Inc. - November/December 2008 - (Page 58) accidents have occurred during these operations due to the size and weight of some of the casted members, and employees have been seriously hurt or even killed by falling panels that had not been stacked correctly, or they were stored in the upright position in poorly designed racks without the proper holding mechanisms. Preparing for prestressing operations This is perhaps one of the most critical operations performed in a prestressing plant, as most hazards can be eliminated by taking the proper safety precautions. Cables, strands or tendons should be carefully inspected during placement in the casting beds to detect any defects that could cause failure under tension. These defects include nicks, corrosion, kinks or broken wires that could weaken the cables and make them snap when force is applied. These defects usually are the consequence of improper cable spool storage and handling, such as exposure to the elements or being hit by rolling equipment. Welding and flame cutting operations must not be allowed near tendons while in storage or once they have been placed in the forms. An electric arc jumping to or from the cable, or the heat from a cutting torch could change the molecular structure of the metal and weaken it. Only shears or abrasive wheel saws must be used when cutting tendons from the spool or for splicing. It is also important to keep tendons clean at all times. Use approved eye protection, leather gloves, steel-toed shoes and hard hats. Chucks, or strand vises, must be kept clean and lubricated. They should be placed away from any distorted or deformed area of the strand, at least 6 inches or 12 cable diameters, The new 40 Series crane handles 40,000 lbs at 10 ft through a full 360 degree of rotation. The solid platform is greatly improved buy the newly designed 20 ft spread rear outriggers. The 40 series efficient design still allows for up to 20,000 lbs payload capacity on a standard 3-axle truck. Call Today for information on our current special. Lease to own a 4030R mounted on a new Peterbilt 365. No money down and payments as low as $3998/month on approved credit. Terms: 82-month lease with $1 buyout at end. Price based on standard equipped crane and truck. Call for Details. Special based on 2008 delivery and production slot availability. BOOTH 821 THE PRECAST SHOW QMC Hydraulic Cranes 58 NOVEMBER/DECEMBER 2008 | PRECAST INC. R 800-331-7959 R 714-754-0337 R www.QMCcranes.com Photo courtesy Nitterhouse Concrete Products http://www.QMCcranes.com http://www.QMCcranes.com
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