Crane Accident in PA

the front outrigger is just there to offset the weight of the cab and engine when working over the front on a behind the cab mounted boom. it should be used so there are no surprises when the operator forgets what he is doing and swings around over the front and the back end gets light. (it can happen even with nothing on the hook). from the looks of some of the posts, some of the tree people running cranes need all the help they can get as they have no training and little common sense.
 
The front one on that style crane helps with overall stability during the whole op. Enough variables to just do it. It's designed to have ALL outriggers deployed. I'm sure we have all at some point gone beyond what we thought we were going to do, therefore plan for as much as you can. It also helps with the frame flex when leveling, at times its jacked high in the front, it will contribute.
Plain and simple, if it has it, crib it.
My question is, did he have crane op cert? Is it "mandatory" as of 2014??
Our insurance company wouldn't ins crane unless we had the cert. we have 3 guys with the cert on the cab mounted style you see there.
 
Sorry but i must disagree...if you don't need to swing over the front, using the front jack when not needed can actually create a minor gliche over the course of time....(at least on the newer longer, stronger, "better" models. As you move throughout you range of motion and "settle in"; differential settlement can actually cause you to start tedering from left to right due to having the front stabilizer, which is not an outrigger, deployed.
 
It is my understanding the front stabilizer is supposed to be the last one deployed and not pick up weight of the crane. So it would not add to frame stability when not moving over the front. If there is weight of the crane lifted then as craneguy1 mentioned it would be counter productive.
 
craneguy1 said:
Sorry but i must disagree...if you don't need to swing over the front, using the front jack when not needed can actually create a minor gliche over the course of time....(at least on the newer longer, stronger, "better" models. As you move throughout you range of motion and "settle in"; differential settlement can actually cause you to start tedering from left to right due to having the front stabilizer, which is not an outrigger, deployed.
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if you set up the crane properly, on suitable dunnage for the surface you are on, this is not an issue and is required per manufacturer.
 
allmark said:
It is my understanding the front stabilizer is supposed to be the last one deployed and not pick up weight of the crane. So it would not add to frame stability when not moving over the front. If there is weight of the crane lifted then as craneguy1 mentioned it would be counter productive.
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you are correct allmark. the front jack has a circuit relief which is typically set at around 500 psi. this allows jack to be deployed after the main stabilizers level the crane with minimal down pressure. once deployed the lock valve holds pressure in jack so when you swing over front quadrant it does not relieve and supports load weight applied by crane. most rigs automatically raise the front jack first if you raise any of the main jacks/stabilizers
 
Thank you guys for clarifying that. So, yes it's a front stabilizer, therefore I will and hopefully all will use what the crane came with. I will choose to stabilize. Front is last to come down, first to go up.
The better bigger ones that was stated before, from what I know, usually don't have it, the frame is strong enough.
When we put our front one down it lifts the cab up just enough to straighten it. That's what it's for and like stated before it is a manufacturer thing, all there is to it.
I wish I had my puter back and running, I have some good pics I could tag with this. Soon I will
 
Sawdust said:
Thank you guys for clarifying that. So, yes it's a front stabilizer, therefore I will and hopefully all will use what the crane came with. I will choose to stabilize. Front is last to come down, first to go up.
The better bigger ones that was stated before, from what I know, usually don't have it, the frame is strong enough.
When we put our front one down it lifts the cab up just enough to straighten it. That's what it's for and like stated before it is a manufacturer thing, all there is to it.
I wish I had my puter back and running, I have some good pics I could tag with this. Soon I will
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the bigger the boom truck, the more a front stabilizer is necessary. it is there to offset the weight of the cab, which becomes part of the load moment when you swing over front quadrant. it has nothing to do with frame strength.
 
I'm not referring to the front "adding"frame strength! Our crane, and others of this style, size, blah blah, when set up at a certain incline/decline, over front(which I'm not a fan of doing), over rear, side... Blah blah blah, if the front, i.e. cab, is lifted due to set up, the frame flexes... Are we on same page yet?? Which causes the front, i.e. cab, to dip... Can we picture that?? Ok, so I'm imagining the engineers knew that and saw that, so the front stabilizer will be deployed and assist in relieving that said deflection of said frame... Still on same page?...I've worked with other "bigger, better cranes" that have a stronger frame that do not require a front stabilizer for that purpose, nor require it as part of the design by manufacturer. Simply put, some have it, some don't. If it does, then use it, keep it simple stupid.(that's just a saying, it's not literal, in case anyone doesn't get that either)
More than what was needed to say about that... Hopefully the semantics are over
 
Sawdust said:
I'm not referring to the front "adding"frame strength! Our crane, and others of this style, size, blah blah, when set up at a certain incline/decline, over front(which I'm not a fan of doing), over rear, side... Blah blah blah, if the front, i.e. cab, is lifted due to set up, the frame flexes... Are we on same page yet?? Which causes the front, i.e. cab, to dip... Can we picture that?? Ok, so I'm imagining the engineers knew that and saw that, so the front stabilizer will be deployed and assist in relieving that said deflection of said frame... Still on same page?...I've worked with other "bigger, better cranes" that have a stronger frame that do not require a front stabilizer for that purpose, nor require it as part of the design by manufacturer. Simply put, some have it, some don't. If it does, then use it, keep it simple stupid.(that's just a saying, it's not literal, in case anyone doesn't get that either)
More than what was needed to say about that... Hopefully the semantics are over
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all your snarky comments aside, if you want to be on the same page, realize that the front outrigger has nothing to do with frame deflection whatsoever and has nothing to do with frame strength. it is a balance issue. it is deployed to overcome the overhung weight of the cab and engine ahead of the main outriggers which if unsupported will increase the tipping moment ahead of the main outriggers. (therefore acting like the crane is actually trying to balance more weight than it actually has on the hook). trying to keep it civil.
 
dbl612 said:
you are correct allmark. the front jack has a circuit relief which is typically set at around 500 psi. this allows jack to be deployed after the main stabilizers level the crane with minimal down pressure. once deployed the lock valve holds pressure in jack so when you swing over front quadrant it does not relieve and supports load weight applied by crane. most rigs automatically raise the front jack first if you raise any of the main jacks/stabilizers
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This sums it up pretty well I think. I just went through getting lined out on how to use the new to me front stabilizer on my National. After I use the 4 outriggers to get level, I deploy the front, and listen for the pop off valve or whatever it is that tells me it is at it's design pressure. I never had one on my BTC boom trucks, or on the Manitex 101S, but I did get real good at blocking the frame rails in the front, (Terex 3470) allowing for a lot of work to be done that direction that would have been unwise or impossible without the blocking of course. Then I really wised up and realized what I really needed was a rear mount rider, it sure is a "force multiplier", getting the crane COR much closer to the work. I did a lot of work over the front with the Manitiex, as long as the tires were not in the air, but in firm contact with the ground it was OK, said so right in the chart.
 
So as I stated before, now the third time, I know it's not a frame strength issue. Yes it's all about stabilizing. I was just... Ahh never mind. The perception is getting further from the intent. Now back to our regularly scheduled program...
Let's hope the bucket operator is doing fine. He got lucky from what it sounds like.
Sounds like the crane op abandoned ship after picking too big of a piece. Also believe he was certified on that crane too, not that that means much, maybe just less fines??
 
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