Slightly scary event today

[SilentTrigger]

No the robot didn't go carusell but sounded about the same.
Was standing by a big vertical center lethe (http://www.machinetooldirect.co.uk/c..._LA-VT-550.jpg, one of these) and they had made this thing to take care of all the metal cutway as it was causing problems, it was a 5 mm (0.2 inches) thick by 1 inch wide by 10 inches long peice of steel.

They started it up and everything went well, just the normal cutaways agains the protective housing. It started to sound a bit louder and then hell broke lose, the thing was smashing around in the lethe and then there was this extreme bang. I had turned my face the other way around and covered a distance of around 6-7 feet from the machine and it had stopped with the help of it's hydraulic disc-breaks. I looked and saw about an inch thick dent in the thick protective housing. Based on the sound i was sure that something would come through the machine, there ware protective see through pastics with metall bars going across it. Was actully concerned for my helth there for a moment. If it had come against the pastics I think it would of gone through.


This is the same type of machine, but the bed that the workpiece is strapped to on the lethes that I work around at the moment has a size of the workpiece in the video and it's alot thicker. Alot of mass in movement.

http://www.youtube.com/watch?v=H6bF3...eature=related


THe metal bar that was to remove the cutways had broken away with quite a nice and straight cut.


I went home after that, they hade quite a bit of work to do (he considered it to be an idiotic thing of course, he was not the one that put it there but was the one who had to sort it out. This is the last time I stand reallt close to these kinds of machines. (Probebly not heh)

[Ronbo*MFA*]

Re: Slightly scary event today

CNC machines are inherently safe to work around.....

There are many safety features such as the brakes you mentioned as well as over-spin fault switches, but you can't predict when a metal part is going to break so that is where an experience operator should be watching the work progress. Many times while working in factories have I seen the operator place the part to be machined in and then walk away to get a cup of coffee or to pick up the magazine he was reading. Thankfully there was no failure on the part of the machine or part.

As far as I'm concerned the operator is being paid to do a job, which means that he stand there to hit the emergency shutoff if something goes awry. Sounds like your operator wasn't doing his job.

While I know that working with Robots is your thing Alex, things go wrong and things break, that is why you need a human element to be in the loop to make sure that if it does someone is there to hit the big red button.

[SilentTrigger]

Re: Slightly scary event today

There's two operators on 4 machines. He was near the machine when it happend but this didn't take minutes, it took seconds so there was not much he could of done.

I have operated CNC machines aswell and have check all their work and they are really professional in their job however the machines should go nonestop and there for they are not shutdown during breaks and such.

[Ronbo*MFA*]

Re: Slightly scary event today

There's two operators on 4 machines. He was near the machine when it happend but this didn't take minutes, it took seconds so there was not much he could of done.

I have operated CNC machines aswell and have check all their work and they are really professional in their job however the machines should go nonestop and there for they are not shutdown during breaks and such.

Like I said for the most part CNC machines are relatively safe, but I am speaking of machines over 25 years ago when most CNC machines are manually loaded.

But like I said equipment failure happens, that is where you need the human element. I've known some really good operators that could tell you where in the process the machine is at by the sound it's making...so if something didn't sound quite right it was shut down as a precaution to save the machine and countless hours of retooling by the tool makers. Sadly we have as a society come to rely to heavily on automatic systems so operators have lost the ability to hear what is going on in their machines. The company I worked for made food service and oil industry pumps, as well as muzzle brakes for tanks and field artillery pieces, so tolerances were fairly tight.