Engineering: how NOT to do it

[Ellirium113]

Don't get me started on plastic

Fine for Lego blocks, but it's mostly useless in the field. Even the ultra-hard PMMA (Lexan,Plexiglass) will go brittle when exposed to UV or heat, in other words, outdoors

Not only falling rocks, but a lot of my problems with sensors was people standing on them

My standard technique has always been to allow for this and house the sensor in a thick pipe welded to the frame, or a thick plate bolted to the frame. This allowed for easy adjustment of the sensor, and people can stand on it.
The drawback is that it may get knocked out of alignment, which will give problems, but it's a lot quicker, easier, and cheaper than to keep replacing sensors.

We have more of a problem where the pipe gets crushed from rock and you must dig it out and change the entire pipe, harness & sensors. We find some loom and keep the wiring as close to the main frame as possible so the upright supports deflect most of the damage or we route the wiring unde heavier components that can take a beating.

I have often replaced nylon bushes with bronze ones

I know these, they are either ON or OFF, must be a real pig to get them out....and i've had cases where the dump valve lever was rusted solid

In our environment we are finding the hydraulic ram attached to the system is corroded and seized solid. We usually just change out the works every so often.

And i hate hydraulic oil,.
Hydraulics are very efficient & flexible, & it would be nice to see one with sunflower oil in it, something more environmentally (& human) freindly.

Anyone want to do some research on that?

It all depends on your hydraulic setup...some pumps need higher detergents and anti-foaming capabilities. Some systems require nothing more than 10w30. There are many companies already working on these sort of oils though for example:

http://www.bio-lubcanada.com/en/our-products/59.html

Been digging in the archives, not much more on BAD engineering, but i've got a whole bunch of GOOD engineering examples from my past.
So i guess that will be 'part 2' of this thread

I might need a new forum, called 'Uncle Luke's Agony Column for Stressed Engineers'
In the meantime, i'm very interested in hearing your stories, preferably with photo's?
LOL

I don't have any good photos of equipment failures here...but next week I'll get you some doozies. 

[Ellirium113]

I don't have pictures as we are not allowed to take pictures where I work. This happened a few months ago.

Yeah many companies are doing this they say because of "espionage" which is a half truth, there is a lot of blackmailing potential if pictures of safety infractions find their way to the inspectors without going through proper channels and reports etc.

On our roof there is a 400hp motor that is part of our cooling system. There is a solid platform where a crane can set it down and a trolley set up to put it in place. they decided that they would not spend the money for a crane. They welded an extension on a fork truck and put 10 55 gallon drums on a counter weight. Stacked skids 8 high and had another lift put the motor on the skids. When they raised it to the roof 2 guys had to stand on the back of of the modified lift to keep it on the ground. The platform is about 5 ft from the roof edge. Then they hooked upped the trolley system and swung it to the platform.

It did work and no one got hurt. I still get cold chills thinking about it.

Bless
Back

That's a crazy one. It's all fun and games until someone loses an eye eh?

[PLAYSWITHMACHINES]

Back, i already got the chills when you talked about 'welding extensions'- this is not only very difficult to do properly, it's illegal. No wonder you can't take photo's
Yes it got the job done, and if the weld is good then OK but it's still a suicide mission to load a forklift like that.

Typical bloody managers taking risks with our lives for a little more profit

Good for you Ellerium

We find some loom and keep the wiring as close to the main frame as possible

That, and place a quick-change plug somewhere near the sensor, AND a junction box here & there, so you only have to replace short lengths of cable

We usually just change out the works every so often.

Preventive maintenance eh?
At least they got that right

Nearly all the pics i showed are from big companies & are of course, illegal.
But what they are doing is illegal, too (or should be) so i say what the heck?

At least i'm not naming names

[zorgon]

When they raised it to the roof 2 guys had to stand on the back of of the modified lift to keep it on the ground.

LOL sounds like what we did all the time at conventions when the big machine displays came in

As to cameras at work... get yourself a necktie spy cam. Then you can get cool pics and no one is the wiser... like these at a DARPA convention revealing the 2004 deployed SBL (space based laser) 








Shhhh I know nothing.....

[PLAYSWITHMACHINES]

MMMM now that's a peice of kit i'd like to play with.
Smaller than i thought, too

I see from the agenda that the whole project was scheduled to be fully operational in....2013

Oops