According to OSHA 29 CFR 1910.217, “The employer shall provide and enforce the use of safety blocks for use whenever dies are being adjusted or repaired in the press.” They also satisfy the lock-out/tag-out requirements for isolating mechanical energy.
Die safety blocks are placed between the die punch and holder with the machine stroke up. They are rated to support a static load. The static load represents the combined weight of the press ram, ram components (ram-adjust assembly and connection rod[s] or pitman arm[s]), and the upper die.
In some applications, as many as four safety blocks may be required. This is determined by the size of the press bed and the weight the blocks must support. On larger presses, the total slide weight must then be distributed among the quantity of safety blocks required.
The ram is usually adjustable; therefore, wedges or the adjustable screw device is offered to provide a proper fit. If the die takes up most of the space on the die set, it may be difficult to find a place to insert the block. To avoid accidentally stroking the press or leaving the safety block in the die after use, an electrical power cut-off interlock system should be used.
Note: Electrical interlocking of die safety blocks to the machine’s motor and control circuits is required by ANSI B11.19.
4199 DIE SETTING:
The employer shall establish a die-setting procedure that will ensure compliance with this section. The employer shall provide spring loaded turnover bars for power presses designed to accept such bars. The employer shall provide die stops or other means to prevent losing control of the die while setting or removing dies in inclined power operated presses. The employer shall provide and enforce the used of SAFETY BLOCKS for use whenever dies are being adjusted or repaired in the power operated press.
EXCEPTION: Press Brakes using general purpose dies. The employer shall provide brushes, swabs, lubricating rolls, and automatic or manual pressure guns so that operators and die setters shall not be required to reach into the point of operation or other hazard areas to lubricate material, punches or dies.