Views: 43 Author: Site Editor Publish Time: 2018-05-09 Origin: Site
Equipment designed to detect people or parts of their bodies and to send a signal to the control system intended to reduce the risk to which the detected people are exposed. The signal can be triggered when a person or a part of his body goes beyond a pre-established limit – for example, when the person enters a danger zone – (detection of the crossing of a boundary) or while a person is detected in a previously delimited zone (presence detection), or in both cases.
(Free translation of French version)
1.Electro-sensitive devices that can ensure safeguarding of the rear zone are, for example:
- a safety light curtain,
- a pressure-sensitive mat,
- a laser scanner,
- several mono-beams,
- a combination of these devices.
2.The safety light curtain is the electro-sensitive device that can ensure safeguarding of the side zones. N.B. These devices must comply with the requirements related to the safety distance principle stated in Appendix 8.A.
Additional information
- CSA Z142-02 clauses 11.3.2., 11.3.5, 11.3.6, 11.3.8, Code for Power Press Operation: Health, Safety, and Guarding Requirements.
- IEC/EN 61496-1 and -2 (2004) Safety of machinery - Electro-sensitive protective equipment.
MOVABLE GUARD WITH INTERLOCKING DEVICE
Definition (CSA Z142-02) Movable guard associated with an interlocking device, in such a way that :
- the hazardous press functions “covered” by the guard cannot operate until the guard is closed;
- if the guard is opened while hazardous press functions are operating, a stop instruction is given; and
- when the guard is closed, the hazardous press functions “covered” by the guard can operate, but the closure of the guard does not by itself initiate their operation.
Additional information
- CSA Z142-02 clauses 11.1.3.4.1 and 11.3.1, Code for Power Press Operation: Health, Safety, and
- ISO 14119: 1998, Safety of machinery
– Interlocking devices associated with guards
– Principles for design and selection. - ISO 14120: 2002, Safety of machinery
– Guards - General requirements for the design and construction of fixed and movable guards.
FIXED GUARD
(Suggested only for the side zones where access is almost never required.) Definition (CSA Z142-02)
A guard kept in place (i.e., closed) either permanently (by welding, etc.), or by means of fasteners (screws, nuts, etc.) making removal/opening impossible without using tools.
Additional information
- CSA Z142-02 clauses 11.1.3.2 and 11.1.3.3, Code for Power Press Operation: Health, Safety, and Guarding Requirements.
- ISO 14120: 2002, Safety of machinery – Guards – General requirements for the design and construction of fixed and movable guards.
In addition to the proposed means of safeguarding (safety light curtain, laser beam device, etc.), several other means, generally intended to improve production, can be used to reduce risks and consequently, accidents. The list below presents some of them, with their advantages and disadvantages:
BACK GAUGE
Advantages:
• Allows the sheets to be correctly and rapidly positioned with fewer risks if the height of the gauge is sufficient.
• Reduces the number of adjustment interventions when it is automated. Disadvantage:
• Possibility of crushed fingers or hands between the back gauge and another part of the press.
FRONT GAUGE
Advantages:
• Allows the sheets to be correctly and rapidly positioned with fewer risks. • May also serve as a fixed sheet support.
Disadvantages:
• May disturb the proper operation of a safety light curtain. • Possibility of pinc
LATERAL GUIDE
Advantage:
• Allows the sheets to be correctly and rapidly positioned with fewer risks. Disadvantages:
• May disturb the proper operation of a safety light curtain.
• Possibility of pinching and crushing between the lateral guide and the sheet.
USE OF A HOIST Advantages:
• Allows heavy parts to be handled, and also avoids certain risks of back pain, impacts, crushing, etc.
• May allow fewer operators to be mobilized.
Disadvantage:
• Requires a lot of vigilance if several operators are working together.
PROGRAMMING THE BENDING SEQUENCE
Advantages:
• Makes it possible to avoid situations in which the opening of the dies is larger than necessary (thickness of the part + 6 mm) to release the parts.
• Limits the blanking of some or all of the safety device (e.g., safety light curtain) to make the final bends.
• Makes it possible to avoid parts hanging behind the dies and therefore the part tipping behind the press.
TRAINING OF OPERATORS AND MAINTENANCE STAFF
Advantages: • Allows accidents to be avoided through better knowledge of hydraulic power press brake operation and of the bending process.
• Helps minimize bypasses if the worker is trained in the operation and use of means of safeguarding.
• Allows personnel to be more efficient in press maintenance and operation.
AVOIDING HAZARDOUS BENDING THROUGH PARTS DESIGN
Advantages:
• Eliminates bending that can be dangerous to perform. (e.g., Bends that create sheet return movement, those that are too close to the edge, etc.). Note: Consulting press brake operators before finalizing the design of the part could be one approach to consider.
• Avoids designing large parts that have to be removed from the side, and as a result, rendering some means of safeguarding unusable (safety light curtain, laser beam device, lateral guards).
UNIFORMIZATION OF DIE HEIGHT
Advantages:
• Reduces the interventions and adjustment times for dies.
• May allow several series of parts to be produced without readjusting the safety devices (e.g., laser beams).
SPEED REDUCED TO 10 MM/S AND 3-POSITION PEDAL [OFF/ON/EMERGENCY STOP]
The reduction of the ram’s speed to 10 mm/s and the use of the 3-position pedal reduce the risk by increasing the possibility of avoiding harm.
• This measure is not a means of safeguarding, but is instead a means of risk reduction. It therefore does not comply with ROHS according to section 182. It is a last resort or temporary measure when it is impossible to safeguard the press brake in another way, or even when the existing safety device must be bypassed.
If this method is permanently installed, there must be proof that it is the only method available for risk reduction.