Safety Blocks

Occupational Safety and Health Administration (OSHA) standard 1910.217 for mechanical power presses requires use of safety blocks.

“The employer shall provide and enforce the use of safety blocks for use whenever dies are being adjusted or repaired in the press.”

Please refer to 1910.217(d)(9)(iv) as referenced in OSHA document:
Regulations: Machinery and Machine Guarding / Standard Number: 1910.217.
Information is also available online from the
American National Standards Institute B11.1-2009 document
Refer to section 9.2.6 “die adjustment, cleaning, or repair.”

Safety blocks are designed to prevent accidental die closure during press setup and maintenance. Safety blocks are constructed from lightweight extruded aluminum or magnesium and are available in fixed lengths with wedges for minor adjustment or adjustable versions. Consideration should be given to the weight of safety blocks as they can sometimes be cumbersome to lift where press bolster heights are well off the floor.

Static load and open height requirements determine the optimal size and style of safety block. See the download sheet for more details or contact our Application Engineers for more information.

Series 42 Protech Safety Blocks

Series 42 Protech Safety Blocks provide safety during set-up and maintenance for power presses. This is done by mechanically and electrically preventing inadvertent die closure. The new model Safety Blocks, Model 42o are for smaller presses, with a maximum static load of 35 tons (having a wide span of adjustable heights). Made of high strength lightweight extruded aluminum. Selection of the proper style and size is determined by the press static load and the required open height. Safety Blocks using wedges are also available, as well as the standard model 42 for larger presses.

Protech die safety blocks are placed between the die punch and holder or ram and bolster 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.

  Series 42 Protech Safety Blocks specifications

Safety Blocks from Saf-T-Block

Standard Safety Blocks

These heavy-tonnage, heavy-weight safety blocks are available in 4 sizes in many difference capacities. 4” to 92” lengths available.

Adjustable Safety Blocks

Feather-Weight (5 Ton Maximum Capacity) & Light-Weight (35 Ton Maximum Capacity)

• Designed to provide maximum protection for most press brakes and smaller presses where working space is at a premium during set up and maintenance.
• Convenient to use and handle, adjusting screw and nut assemblies offer a wide span and have precision-cut Acme threads for extra strength. The 6061-T6511 high-strength aluminum body is machined for ultimate stiffness with maximum adjustability at a minimum weight.

Mid-Weight Adjustable Safety Blocks (75 Ton Maximum Capacity)

• Specifically engineered to be used between the Light-Weight and Standard adjustable press blocks.
• Available from 10″ to 60″ by the inch with the option of 5″ to 12″ of screw adjustment. This safety block is easily stored in Saf-T-Block’s optional press-mounted holder. These blocks are also available with Saf-T-Block’s electrical power cut-off system.
• Base plate included.

Heavy-Weight (125 Ton Maximum Capacity)

• Standard screw adjustability is 5 inches, but screw adjustment up to 12 inches is available.
• Used in place of wedges, an adjusting screw and nut assembly provides easy adjustment by hand and allows for greater flexibility. The adjusting screw and nut assembly is mounted securely on top of the safety block at the factory. A bottom end cap is used for additional stability and safety.

Available with handles, holders, and power cut-offs.

• Use only certified material, preferably aluminum. Aluminum is malleable, and will deform. Magnesium is supposed to fracture at a 45 degree angle, but can fracture and cause shrapnel. Steel should never be considered due to potential shrapnel issues.
• .250″ of daylight. Under no circumstances should there be more space between the top of the Die Safety Block and the die, or between the top of the Die Safety Block and the slide if the die is absent. It is absolutely critical to accurately calculate the needed Safety Die Block length. An opening greater than .250″ changes the force of a moving slide from static to dynamic.
• If two Die Safety Blocks are needed, they should be placed at diagonal corners.

Slide Locks

Slide locks are an alternative to press safety blocks, which can be time-consuming, cumbersome and physically demanding to use.

The Pascal Slide Lock System (SLA) is an electric slide fall protection system that eliminates the risk of physical injury, accident, or damage to the tool. One of the most significant advantages of the SLA is that the operator can lock the press slide in any position between T.D.C. and B.D.C., all with the flick of a switch in a few seconds compared to several minutes to place die blocks.

While slide locks are expensive compared to the die block and retro-fitting requires some skill, the cost of slide locks is easily justified, due to the safety, ergonomic, and time saving benefits.

Available in three sizes:

• SLA32, which can hold a 35 U.S. ton ram and upper die
• SLA50, which can handle a 55 U.S. ton ram and upper die
• SLA80, which can hold an 88 U.S. ton ram and upper die

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