Document Ra64nw8gKkKVmx7mOOXqbYb5z

Machine Tools severed and arms severely cut One fatality has been reported from a coil which became snarled around the operator's neck Opera tors should remove the tool when necessary to allow the swarf to break off The chuck of a spinning lathe is usually a form built up of hardwood, shaped exactly like the finished part If the piece being worked must be "necked-down" so that after the piece is formed the chuck cannot be taken out, the chuck is made m sections held to gether by locking rings or locking grooves There is a definite hazard from such a chuck's flying apart if the grooves should be come worn or the nngs should break In view of the speed of spinning lathes (500 to 2000 rpm), the danger of flying sections ofthe chuck is obvious Prevention of injuries from this cause lies in periodic inspechon and maintenance of chucks Similarly, lathe tools should be inspected frequently for cracks m the handles or in the tools themselves On some older equipment, vibration or worn parts may cause the tailstock to loosen during operabon and the piece to work loose or fly off, exposing the operator to almost cer tain injury Again, the solubon is frequent inspection and maintenance Gear cutters In the operabon ofgear cutters and bobbers, both the tool and the work move during the operabon As a result, the point of operabon guard should be simple and easily adjusted On operations where the work (gear blank or rough-cut gear) is moved to the tool, a simple barrier guard, formed to cover the point of operabon and sized to fit the work, is sabsfactory The guard can be mounted on a spindle that carries the work so that the guard will fit over the point of operabon when the work is brought into posibon When the tool is brought to the work, and when the tool and work are adjustable, an encircling type of guard may be attached to the tool head Such a guard can be an automabc dropgate device or can be equipped with a release latch to open the guard en closure or a spring release to return the guard to a posibon clearing the work Each guard should have an automabc interlock so that the machine will not operate except when the guard is in place On some makes of machines sbll m use, the lever which controls the direcbon of operabon of the spindle is located so that the operator's hand may be caught on the back gears driving the spindle An auxiliary lever should be installed which can be op erated at a point outside the danger zone created by these gears On large machines where the operator may not be close to the regular control switch, a pendant switch mounted on an arm or sweep should be installed to operate a magnebc brake so that the machine can be stopped in stantly When the operator inserts an arbor into the spindle, he should be sure that both arbor and spindle holes are clean and free from nicks He should draw the arbor firmly into place by a sleeve nut, and securely bghten the nut Before he removes the arbor from the spindle, he should make certain that the machine is at a standstill Planing Machines Similar to a carpenter's hand plane, a planer machines a metal surface with the cutbng tool held stationary while the work is moved back and forth underneath it Shapers are gen erally classified as planing machines, but the process is reversed--the work is held station ary while the cutting tool is moved back and forth Other machine tools coming within this classification are slotters, broaches, and keyseaters Planers and shapers Planer accidents result frequently from un safe prachces which are basically problems of training and supervision 1 Placing the hand or fingers between the tool and the work 2 Running the bare hand over sharp metal edges 3 Measuring the job while the machine is running 4 Failing to clamp the work or tool securely before starting the cut 5 Riding the job 6 Having insufficient clearance for work 758