Ask the Experts
Show Per Page:
Inside of a robotic cell, is there a minimum required distance between conveyors or any equipment in the cell for aisles or access? Does RIA have definitions? OSHA? CSA?
Are there any standards addressing colors for robots or automated equipment?
I am doing a risk assessment on a robot cell where boxes go in on a continuous running conveyor to be fill-up and then go out of the robot cell. The opening to let the boxes go in and out is around 24 inches by 24 inches. A human can goes in by this opening. To protect the access, we can not use a light curtain with muting because the distance between the boxes is extremely variable. Is the use of a 36 inch-long tunnel is a good safety practice to move the operators away from the danger even if a suicidal one can lay down on the conveyor and goes in the robot cell?
Your solution is much more cost effective than the mechanical door, however if an operator really wanted to get into the cell, the tunnel would not keep him out. With a mechanical door, logic could be programmed into the controller to shut the machine down if the door was opened without a box passing by the appropriate photo cell. S Diebold WireCrafters LLC wirecrafters.com
We are moving several robots from one building to another 240 miles away. The current shop has been in production for 10 plus years. Production will stop and everything must move. Is there a new stet of standards that must be applied and do I need to update the old equipment to the new standards (if any)? Where do I get a road map to help in this move?
Steve Diebold WireCrafters LLC 800.626.1816
Is there a defined minimum width defined for a robotic cell door other then common sense?
- President
sdiebold@wirecrafters.com
(800) 626-1816
We have a robot that is enclosed by a wire fence enclosure 8 ft. in height that has a 32" wide access opening covered by a 36" wide interlocked sliding door. When the door is in the closed position the left hand side of the door is restrained by the upper track at the top, and by a channel shaped guide at the bottom. The right hand side of the door when closed is likewise restrained by the upper track, and is captured at mid frame within a channel shaped latch mechanism and at the door frame bottom by a channel shaped slam plate. This hardware is secured in place by tamper proof fasteners and captures and brackets the door within the channel shapes and will prevent the door from being pulled outward so as to potentially permit an individual to pass behind the door and to enter the cell. Will this door arrangement comply with R15.06 Clause 11.2.1 (e)?
Reference ISO 14120 "Safety of machinery - Guards - General requirements for the design and construction of fixed and movable guards", Second edition 2015-11-01 5.3.12 Movable guards, which states that attachments shall only be removable with the use of a tool.
Specifically, in regards to your question, yes, I believe that communicated design effectively "complies" with the ANSI/RIA R15.06-1999.
Other standards in regards to interlocked guards: ANSI B11.19-2010 "Performance Criteria for Safeguarding", ISO 14119 Second edition 2013-10-01 Safety of machinery - Interlocking devices associated with guards - Principles for design and selection", and RIA TR R15.406-2014.
Erik Johnson - Innovation Manager
ejohnson@wirecrafters.com
(502) 357-7264
I design automation cells and regularly have conveyor openings in fencing. I've read through the RIA safeguarding manual but can't seem to figure out the proper distance I need to have hazards from the fence/tunnel end. The best I've come up with is treating a hole in the fence bigger than 4.7" as a reaching over scenario which doesn't quite seem correct.
RIA TR R15.406-2014 Table 7 "Reaching THROUGH or AROUND a guard or protective structure" states "Openings within a guard >120mm (4.7 in.) are not permitted without additional safeguarding"
ISO 13857 4.2.4.1 "Reaching through regular openings - Persons of 14 years of age and above" states "For openings > 120mm, safety distances in accordance with 4.2.2 shall be used.
I agree that ISO 13857 4.2.2 "Reaching over protective structures" is not sensical in my opinion, to calculating minimum safe distance(s) based on an "e" dimension.
I acknowledge that the aforementioned does not answer your question. Please feel free to email me directly ejohnson@wirecrafters.com
Erik Johnson - Plant Engineer
ejohnson@wirecrafters.com
(502) 357-7264
If I'm not using any safety devices in my robot cell, what equation do I use for safety distance? I believe S = K*T + C is only for used with safety devices, due to the variables dealing with human interaction speeds. Is there a general equation for safety distance with regards to fencing and so maintenance personnel can't get pinned?
ISO 14120 (General requirements for the design and construction of fixed and movable guards) states that guards intended for preventing access to hazard zones shall be positioned to prevent parts of the body from reaching hazard zones according to ISO 13857 (Safety of machinery - Safety distances to prevent hazard zones being reached by upper and lower limbs) . For interlocked movable guards, safety distances according to ISO 13855 shall also be fulfilled.
There are several factors that affect the safe distance of guards, to include but not limited to, protective structure opening dimensions, type of opening (i.e. slot, square, round), height of the protective structure, height of the hazard zone, etc.
Erik Johnson - Innovation Manager
ejohnson@wirecrafters.com
(502) 357-7264
Hello, In R15.06-2012, it states that there is a maximum height a barrier can be above adjacent walking areas is 7". This is to ensure that no one can come in contact with the equipment inside. In applications where there could be large build ups of combustible dust or require routine cleaning of the area, is there a different height/ acceptable alternative to the 7"? Currently there is an installation which the eentire robot system is shutdown in order to clean the area due to the height of the guarding. This dramatically hinders production and could potentially cause employees to attempt to defeat the guarding to maintain the equipment. Thank you for your help
ANSI RIA R15.06-2012 Part 2 5.10.4.2 states "ISO 13857 shall be used to determine the appropriate dimensions for the opening from the bottom of the guard to adjacent standing surfaces and any openings in the guard" (also shown in figure 12)
RIA TR R15.406-2014 states "... the opening between the walking surface and the guard shall be no greater than 180 mm (7 in.)." Note 2 states " In Canada, CSA Z432 and Z434 require a lower dimension of 150 mm (6 in.) .."
Erik Johnson - Innovation Manager
ejohnson@wirecrafters.com
(502) 357-7264
We are considering a new robotic cell to pack our product in large re-useable totes. The opening in the barrier guarding is more than large enough for a human to enter. We intend to protect that opening with a light curtain. Even so, is there a minimum distance the robot's controlled movement must be from the entry point of the barrier opening? If so, what is that distance?
The ANSI for Robot and Robot Systems (ANS/RIA R15.06-1999) uses the following formula to determine the safety distance for your presence sensing safeguarding devices
Ds = [ K x (Ts + Tc + Tr)] + Dpf
Where:
Ds = minimum safe distance between safeguarding device and the hazard K = speed constant: 1/6 m/sec (63 inches/sec) minimum based on the movement being the hand/arm only and the body being stationary Ts = worst stopping time of the machine / equipment Tc = worst stopping time of the control system Tr = Response time of the safeguarding device including its interface Dpf = maximum travel towards the hazard within the presence sensing safeguarding devices field that may occur before a stop is signaled. Depth penetration factors will change depending on the type of device and application.
That ANS/RIA R15.06-1999 also has several charts and tables that are pretty handy concerning this topic and probably not a bad idea to take a look at.
Gary Bruner - Production Direction
gbruner@wirecrafters.com
(800) 626-1816