Crane tip-over.

[treevet]

TreeVet,

I agree with you about chart numbers going out the window when dealing with wood chunks still on the trunk.
I prefer to keep loads in trees to 50% of chart limit. If I was using the crane hoister posted the chart for, I may lower it to 25-33% of chart limit, if that limit is structual. A chunk doesn't have to fall far to hit with 2 G's. Structual overloads happen instantly in steel. Even if it doesn't fail then, it remembers the overstress and can fail at a lower limit later.

The crane I'm currently running is at a home construction site on a mountain. It is sitting with the front of the truck higher than the rear. ( about 10 degrees ) That throws the chart out the window as well.
Rick

Great points VA Sawyer....besides being off level you need to stay away of being marginal when cribbed to the max as well. We have a very hilly town here and have had my crane and a subbed 30 ton truck crane with the bumper well over head level in some jobs.

This is a great informational thread. One thing not discussed very much is the crew (aside from the op and the climber). IMO these jobs are the most demanding for ground personnel of any in the business. In this case it involved communicating from the back yard to the front yard while blind (which we do quite often). Sometimes the op cannot even see the climber on picks and this is even more dangerous. Walkie talkies are advantageous
but only somewhat. This job likely involved the gm communicating and identifying weights of picks. There had been numerous picks beyond (boomed out even further) the catastrophic pick prior to the house so they must have been correct in these estimates or....again it was the case of the piece still attached to the trunk that caused the dirty deed.

Also the gm needs to be highly skilled at cutting under pressure and recognizing that pressure. When the op sets a piece down in a very tight spot that will not fit the piece then it has to be whittled down quickly, efficiently and professionally. No newcomers wanted here. I had a new crew once where one gm was a decades old experienced pro and his buddy was not. We were booming into a very tight spot. I was in the tree. If I am in a bucket I don't mind booming down sometimes to help out.

But I gave explicit orders that the relatively inexperienced new guy was not to even TOUCH a saw. Well, I guess the guy thinks he knows more than I do and next thing he is cutting a hanging piece up and damn near cuts his leg off. I had to come out of the giant tree and take the dumass to the hospital while the crane was on the clock.

He didn't even want to use my WComp and because of that my guess is he had drugs in his system. He was fine except for a bunch of stitches. But a dumass like that prob gonna get run over on the street at some point.

 

[Hddnis]

The City of Vancouver has just instituted a maximum $10,000 fine if any tree greater than 8"dbh is cut on private property WITHOUT a permit.

The notion of personal property rights is idyllic at best. It has never truly existed and never will. Regardless of where you live, you can't open a toxic waste dump in your backyard, or build a 37 story skyscraper on your city lot.

Shame on the city of vancouver.



Mr. HE


P.S. I didn't capitalize because vancouver just went down in my opinion.

 

[ROOTSXROCKS]

it seems to me that personal liberty with property ends when it affect the liberty and enjoyment of your neighbors property.

removal of large trees affect the surrounding properties and the ambiance of the whole street.

so Yeah Im behind the city on this one, a permit Inspection to validate the necessity to remove is a good thing.

 

[Hddnis]

Well, then I'm glad you live on the other side of the country. Maybe we can ship some like minded people over to live with you.:greenchainsaw:



Mr. HE

 

[ROOTSXROCKS]

were the houses are more than 15 feet apart, I think this is less important, but here a lot of snowbirds want to clear cut so there precious winter homes are "safer" from the hurricanes during the summer when they are away. regardless of the impact that the loss of canopy has on the rest of the ecology and micro climate.

however Even On vast acreage if your actions detract from the vistas and beauty of the area, I see were fellow owners might want to do something.

 

[treevet]

I have called my city's government numerous times to see if they want to give input in a decision to remove or leave a historical tree when it has become dangerous. I have given up as either they do not want the liability or they are confident in my basis and knowledge for decisions.

In any case more often than not, the local government will not have someone capable of being the deciding force in such a predicament. A highly educated and ethical private arborist will most of the time be the right one to make the decision.

My inclination if I was just a homeowner would be to talk to 2 or 3 highly reputable arbs and make my own decision based on that rather than having the govt. (yeahhhcccchhhh) get involved.

 

[John Paul Sanborn]

it seems to me that personal liberty with property ends when it affect the liberty and enjoyment of your neighbors property.

I agree, though some communities take it to extremes; no parking in the driveway, keep the garage door closed at all times, no parking of an RV...

I am in favor of property maintenance ordinances that are similar to building codes. Since you will be passing on the property, you cannot alter parts that will cause problems for future owners. Such as lopping large low limbs, topping, poor planting practices, driveways right next to very large trees. Though the last is a big money maker for me

 

[Adkpk]

There should be some federal laws written up and handed down to towns to use. Reports would be made up and rewarded with funding for towns who are complying and showing signs of interest to their trees. If you look after your trees then your probably looking after the rest of the town and therefore doing responsible things with federal funding.

Many things about trees and wood are becoming very valuable and we need to protect and educate people to this.

If the guy who sold that tree job needed a permit to remove that tree I bet it would be still be providing shade and a beautiful sight to the neighborhood.

Look at it this way: if that tree was across the way from you, providing you with that view in the pic and one day your came home to find it gone. Asking and finding out the tree was healthy, wouldn't you wish you had some say?

 

[treevet]

There should be some federal laws written up and handed down to towns to use. Reports would be made up and rewarded with funding for towns who are complying and showing signs of interest to their trees. If you look after your trees then your probably looking after the rest of the town and therefore doing responsible things with federal funding.

Many things about trees and wood are becoming very valuable and we need to protect and educate people to this.

If the guy who sold that tree job needed a permit to remove that tree I bet it would be still be providing shade and a beautiful sight to the neighborhood.

Look at it this way: if that tree was across the way from you, providing you with that view in the pic and one day your came home to find it gone. Asking and finding out the tree was healthy, wouldn't you wish you had some say?

What I always tell a HO with a huge decurrent tree standing isolated or many marginally threatening trees is to talk to your insurance agent if you are bent on keeping them all, and make sure you are covered in any event of failure outside of negligence. Make sure the deductible is not a killer too.

I was surprised how much my agent says it costs to add such coverage on to existing HO ins. policies.

 

[Dalmatian90]

That is true, but he doesn't explain that it also reduces the radius from center. In order to maintain the same working radius the boom ( lever length ) has to get longer as the boom is raised.

Ah, gotcha -- yes, I wasn't dealing at all with operating radius. The math does work out for a lift at any given operating radius the torque will be the same regardless of the elevation, like the chart posted above shows (within rounding errors anyway).

However, PDQL was also saying:

An example might be a 10,000 lb log 100' feet away from the crane. If the tipping torque of the crane is 1,000,000 lbs, then it will tip over when extended out while picking up the log.

And that's only true if the boom is extending out 100' at an elevation of a right angle since sin(90º) = 1.

Once the boom comes up at an angle, you need to figure in the sin(a), a being the angle between the boom and load, which will always be equal or less then one thus reducing the torque.

 

[Taxmantoo]

Look at it this way: if that tree was across the way from you, providing you with that view in the pic and one day your came home to find it gone. Asking and finding out the tree was healthy, wouldn't you wish you had some say?

Hey, I might want to watch the neighbor sunbathe in her backyard too, but I have no say on when she gets to go inside.

 

[Hoister]

Thought there would be more answer's ..dont be worried about getting it wrong ..most knowlegde is obtained from mistakes ..

here's how you faired
VA Swayer .....


#1 = 94ftboom,at 65ft radius ..
Theres only one right answer here ..because often an operator will be asked .."what can you do with xxxxlbs?(3500 an example)" the answer is 65ft ..in your head you'll know to squirt out 94 feet ..its friutless to drive out 110 then retract to 94 feet..To your favor you'll know youll have to retract to 94 feet to make the lift..

#2Nope thats not a type-o.. Its exactly what i said 100ft..
Sometimes you'll find yourself under a ceiling ..be it a bridge,tree, heavy industrial setting like power generation plant,concrete plants ,,where theres an obstruction everywhere ..you'll find more often that your using intermediate boom lenghts..
So 100ft boom @60ft
Using the range diagram,I measure using the vertical scale 100 feet using the edge of a piece of paper ..make my tick..the using the corner as the pivot ..i boom down to 60ft on the range diagram ..I find my self @52deg main boom angle ..
In the 110 ft m-boom chart ..I go down to the nearest 52degree to 51degrees ..ajacent to that is a capacity of 2700lbs
With 100ft of main boom @60 ft radius ..my gross capacity is 2700lbs


#3..Yup you nailed it ..

You over thought the second thinking it was a typo i think ..


They'll send this in next time ..

 

[asetree]

My buddy who is good with photoshop made this when I showed him this pic.

 

[ROOTSXROCKS]

poor planting practices, driveways right next to very large trees. Though the last is a big money maker for me

hey Ill trade 20 years worth of cool shaded car for re pouring concrete.

 

[treevet]

At first glance that looks like it would tip if you hooked up a loaf of bread to it.

 

[Hoister]

Shes a Liebherr LTM1300.. a 300metric ton hyraulic configured with super lift and luffing jib

Its actually in rigging mode ..the crane is in the process of erection or dismantling ...

 

[John Paul Sanborn]

hey Ill trade 20 years worth of cool shaded car for re pouring concrete.

Who cares about concrete, I'm an arborist and care about tree mortality and risk. Construction activities in the CRZ increase that.

 

[ROOTSXROCKS]

I'm thinking the oak I planted 4 feet from the edge of my drive is Happy, in 7 years the little 1 inch culled live oak with low branching has nearly outsized the Live oak across the street which was a 6" 20 footer when it was planted.

when it comes time to replace the concrete I have pavers in mind that can be reset when needed. the tree has priority and getting into my car without burning something as well as the climate it created in the front yard is more valuable than any potential problem in 40 years.

 

[John Paul Sanborn]

I'm thinking more along the lines of a 20 inch basswood that has paving in the CRZ, or asphalt up to the basal flair. Mature trees that will go into decline and become hazards in 10-15 years. 30 inch red oaks that are 4 feet from the foundation....

 

[rbtree]

welcome, hoister. I've missed the last few days here. Lots of good talk!

Here's video of the recovery:

http://www.youtube.com/watch?v=e8HG7r96bBk

And, I joined this forum and made this post:
***********************************/Forum/showthread.php?t=15430&page=3

Certainly some knowledgable/experienced guys there, but I think the discussion here is better.