Ask the Stamping Expert: Do we really need die safety blocks for die setting?

A: You must meet OSHA 1910.147 lockout/tagout standards at all times during die setting. Any time you need to put your hands in the die area of a press or you need to work on the die, you must use die safety blocks. This is mandated by the OSHA regulations, and there are no exceptions.

The safety blocks, or jacks, must be fitting with dummy electrical plugs on a metal chain connected securely to each safety block. When you remove the safety blocks from storage and put them into the press or die, you have to remove the plug from the socket in the safety block storage area. That socket is wired to the press’s main motor run control circuit. When the plug is removed from the socket, the circuit is broken, and the main motor cannot run.

Before you go into the die area you must visually confirm that the main motor and flywheel have stopped.

This all takes time and is a troublesome task, but it is absolutely necessary for safety.

The safety blocks are designed for gravitational force to support only the weight of the press slide and the weight of the die. When the flywheel is turning, enough energy is available to crush the safety blocks if the press clutch engages.

Presses fitted with front and rear safety light curtains or guards can run continuously only when the light curtains or guards are operable. If the light curtain is broken or guard opened, the press must stop immediately, not continue and stop on top.

The inch mode must be designed to be a two-handed control function. You must have both hands on the two inch-control buttons to make the press inch over. The two buttons must be set a certain distance apart so that they cannot be operated with just one hand. They also must be arranged electrically so that one button cannot be tied down to make the function take place. If one of the buttons is a switch, it must be spring-loaded to return to the safe mode when released.

Protection also is needed for any other person in the press area when inching, so the front and rear safety curtains or guards must be operable.

Because so many variations of part and die design and so many different circumstances could apply to your 100- to 400-ton presses, I cannot give you a defined answer about OSHA’s minor servicing exception.

I can tell you that OSHA does not require the lockout procedure for minor adjustments or service activities if they are a part of the normal production; if the unexpected energization or start-up of the equipment would not affect the operator’s safety; or employees are provided appropriate protection. At no time should you perform adjustments or service within the point of operation or other hazardous area without taking proper protection measures that meet OSHA and ANSI requirements.

OSHA’s minor servicing exception must not and cannot be used as an excuse to deviate from 1910.147 procedures.

The minor servicing exception for normal and repetitive issues must have written safety procedures documented specifically for that process and authorized by your company and safety department, with training given before the implementation of the process.

I cannot emphasize enough that you must adhere to these procedures to protect everyone in your press shop and your company’s liability.