question for operators...overide

[mostlyred]

i dont post much ,but i do read a lot... i know nothing about operating or operation of a crane...i use to work with company that built modulars for hospitals..... of course cranes where hired for both loading and setting these on site,and have seem thes e operators do some scary things..you probably wouldnt beleive if i told the story anyways. i just would like a little more info on the overide?does the on board computer disable the system if it has reached its max..so you hit the overide to continue going more over the limit?i just wondered if this is safety device why do you overide?

 

[willie59]

Actually, the LMI or anti-two block override is there in case there is a fault with the system that won't let you boom the machine down or winch the cable up. It really shouldn't be used to get "just a little farther out" with a load.

 

[yvettessherpa]

The cranes we load test at work have to be put in override to perform the test. We lift 110% of the cranes rated load and the crane handles it fine. However NO operator should be overloading any crane they are using. If they do they are just wanting to hurt someone....

my .02 cents

 

[heavylift]

the override key on the panel will let you continue a function... turn key push and hold a button ...

the computer key will disable the system but continue to signal a warning but won't lockout crane functions
I have recently been operating a crane where it is working at a continuous two block... which requires the computer to be disabled... beep beeep beeeeeeeeep for at least 30 minutes at a time.. Impossible to use the panel override... The lifts are about 80+ feet in the air next to the ceiling... But the signal person watches the boom tip as he is also just a few feet away from the tip also.

most companies don't leave the computer key in the machine... but it is a needed option for this job...
I've worked for companies that removed the panel and computer keys...

 

[cranetools]

The override is for maintenance purposes and in the case of system failure. It is never advised under any circumstances to override the safe load system to complete a lift.
There are many reasons operators use the override key or leave the system in override.
I have traveled Europe, United States, Canada, South America troubleshooting LMI systems and electronic controls in cranes and I can tell you that 70% of all cranes I get into have the override turned or clearly have a device at the key switch or on the dash to override the system.
This is why the new European EN13000 rule for building cranes require the override key to now be located outside of the cabin and the use of a set-up switch that will limit operation speed and function when used in the cabin only.
Also included now in most cranes is that when the key is turned the data logger then records all important operational data like radius, load on the hook, outrigger configuration, function being used & more.
In the case of accident or warranty claim the manufacturer has some back up so to speak. You will see this in all newer cranes very soon along with telemetry data to better manage the fleet.
It is important to remember that every operator has a professional responsibility to all members of the team on every job site!
Think First - - Be Safe!
www.cranetools.com

 

[heavylift]

I would never use it to overload a crane.. just to position the load at at the required height... 11,600# was the max load for that configuration... most of the loads weighed in the 6000# range... a few 8000#
I did take a pic of the LMI 94 feet of boom, 91 feet floor to center of sheave,62 degrees...
The finished height of the steel was 80 feet...
The boom out 6", the lower the load 6".. more out.. then boom down 6"... load down... It probably took 30 to 40 movements to position the steel... a 26 foot tall by 10 foot by 10 cage type affair..

I like the LMI it gives valuable feedback...

I even mentioned the fact to the boss that if the ever downloaded the computer that they may be able to see the overrides..

 

[mostlyred]

a big thanks

first let me say thanks for the info: secondly crane operating is a very skilled and dangerous job,for operators,oilers riggers etc..when ever we were loading or setting these modulars i was always thinking if there is some failure i want to be out of harms way,,after thinking about it i wish i had taken pics of the crane and modular that was being set in the wee, hour in am after a long day of cribbing repositioning.etc..i am sure operators here would have saidto the operator and his boss ARE YOU CRAZY OR JUST PLAIN STUPID...everyone ccame away lucky and safe that night..i would try to explain the situation but iwill saythe load was over the back riggers and the front of crane was lifting ,by time got load boomed down enough to clear back of cranefront was 4 or 5 ft high to this day i dont know what kept it from going over.maybe because it was acatholic hospital we was working.be safe and have good day ...thanks again everyone

 

[Tiny]

That sounds like a lot of luck and Some intervention may have happened .

I don't like to see the key in the switch , But don't like the idea of it not being in the cab . If a 911 deal happened it needs to be where it can be used .

I have heard pros and cons both ways . Being in the field..... I prefer the key close.

IMHO If a Guy or Gal tells me that you have to override to get the job done . They are nuts and need replaced .

 

[heavylift]

well just reading your last post... mostly red... my guess is the crane is seriously overloaded...
Just clear of the outriggers is a stout area as to capacity ... on a 40 ton ... 8 foot is 80,000, which a nearly impossible area to lift... 15 foot is a more practical area to start when figuring a crane capacity in my books...
10 feet which would be the outriggers and 72,200
12 feet... 61,000
15 feet... 47,950
20 feet... 34,550
now this is for 32' of boom...
10 feet to 20 feet of radius and you have lost almost half of the crane's capacity

Think it's time for a new operator

Find your crane load chart online and get the load chart... I think it would help you...
as a aide to help set the crane up in a safer manner...

just my opinion

another thing as the crane was tipping it was losing even more capacity... I think one book says 3% out of level is 30 % less capacity...

 

[Tiny]

Depending on the machine , If Its a rubber tired machine too much of the weight on the tires will make for a situation like that .

At any rate I agree with heavylift ,Think it's time for a new operator

 

[Impact]

I know I'm setting myself up here with you safety conscious guys. But, I'm a big boy with broad shoulders.

We will push the override swtich on occassion to set a piece of steel. I don't think we're nuts either. Both of my crane operators are instructed to call me BEFORE overriding the LMI. We discuss job site conditions, such as Soil bearing. Is the site muddy, or is the ground firm. Which outrigger pads are you using? Sometimes we're setting on cribbing blocks. Sometimes we may be setting on 6' x 6' wooden/steel pads we've built for sloppy conditions. Are you absolutely SURE you're not over any excavations? That's something we check EVERYTIME we set our cranes up, BUT, if we're going to overirde, we triple check. On one call asking permission to overide, we were set up on 21" thick concrcte footings 10' wide poured in a 110' diameter. I don't think the outriigers would punch through the dirt there. What weight are you picking? How much radius do you lack? If we are set up with a long boom, working at a 80' radius, and lack 2' setting the piece, we'll override. If we lack 8' we'll move the rig.

If you override the LMI , you're in a major danger zone for sure. You have to know your machine and it's limitations and use good judgement.

Go ahead and beat me up, I can take it.

 

[cranetools]

The problem with taking this approach is that many newer cranes and their LMI's are set to protect the operator and the job site from a possible crane accident. Crane accidents do not only occur because of bad ground conditions. In todays newer cranes many of their load charts are NOT based on tipping but on structural capacity another words - the boom will bend BEFORE the crane tips over or the ground gives way. Where that breaking point is only the manufacturer may know BUT they will never tell you this piece of information.
It sounds to me that you are tying to be proactive and take the necessary precautions so as to not have an accident but please consider all the possibilities and the possible repercussions of this type of action. Remember if the operator calls in and you tell him yes it SOUNDS okay to override and there just happens to be an accident I am pretty sure that operator will throw you under the bus and tell the investigator that he was told it is okay to override by the owner. Under the new crane rules in the U.S. BOTH the operator AND the owner will be held liable as well as the job site contractor!
Besides you ask questions of the ground and some other good questions but I did not hear you say you calculated the ground bearing pressures from the outrigger load chart and understood the nature of outrigger loading and ground bearing capacities as well as having the proper outrigger ground supports for the type of soil condition. How did you check the ground area? Jumping up and down or it looks good do NOT count!
Think First - Be Safe

 

[Impact]

How did you check the ground area? Jumping up and down or it looks good do NOT count!

The outriggers were setting on a concrete foundation 10' wide x 21" thick and 305' long reinforced with 40,000 pounds of steel. I didn't jump up and down on the footings to see if it would hold, but, I like that idea.....Next time I will...& I'll snap photos.

 

[BigIron25]

Some companies like to ask operators *ahem* I should say encourage operators to use the over-ride key way too liberally to make thier estimators look good or to make the company look good, so you dont have to break the crane down and move the center pin closer to make the pick, of course that all costs more money to move the crane and costing more money and time is generally frowned upon. But of course when something fails on the crane, its the operators fault. In a career that is basically built on reputation of skills, who really wants to throw the dice that often? Im more afraid of overloading squirt booms honestly than conventional crawlers. Its not always going to be the ground that gives way, or the crane that flips over. I see guys all the time overload the cranes capacity way over 100 percent of the chart... especially for crawlers, and my thought is, yeah the crane is designed to be loaded over 100 percent of the chart, but not intentionally and continuosly... so how long can you overload a crane before the boom buckles from stress? How long until the welds on lacings crack or chords begin to twist? Pennant lines stretch and expload? Alot of these guys dont realize that metal can become fatigued, and if they do realize it I wonder if they think they are the first ones doing it? Its a big gamble in my opinion because our best friend Murphy is always peeking around the corner waiting to kick us in the ass! And the boss is ready to cuss us when we didnt chance it...

 

[joelmartin]

Over ride info

I realize this is an old post. Another thing that can happen is you just fatigued the boom by overloading it. You think you got away with it.
Typically it could be several months later after many cycles of flexing the steel, possibly a different operator will be performing a light pick when, "SNAP" it may not buckle but merely open a long crack / seam.
Now what ya gonna do?

 

[mostlyred]

want to say thanks for all the replies...the company that i worked for , which built these modulars .would hire crane and riggers etc...to lift and set these modulars...i personally have no crane operater experiecnce ...i wish i could remember the tonnage and brand of crane in question..was several years back when we did this set.it was hydraulic though and failrly new one at that...when crane company where hired they where given all dimensions and weight of the modular...it was up to crane company to inspect site.and get adequate size crane to do the job...and a lot of times crane came undersized...be safe and just do what crane specs are certified to do..take no chances we were extremely lucky on this occasion

 

[gostr8r]

The O/R functions are there for emergency situations, i.e. inspections [like booming down, within stable ratings, to see the head section area], repairs, load testing or proof testing, and are to be used with extreme caution. Not to be used to overload, or exceed ratings, not to be used to avoid moving the crane so as to be within it's charted capacities. The bottom line is, it's an operator's job to stay in chart, use his professional skills and judgement to make all lifts safely and and successfully. An operator that says he hasn't cheated is likely not being honest, but the better operator has now learned his lessons [hopefully not the hard way] and does it right from then on!