huangyhg

crane collapse in texas
my guess would be that some of these links might have better up close info than the bbc - no disrespect meant for the bbc (in this case anyway.)
there are other links available on the chron's website.
rmw
now i will come back and post a comment.
i don't tend to run with the knee jerk crowd that always wants to overact to any slow news day spectacular of the day but the constant drumbeat of crane disasters is beginning to be troubling.
i don't know the facts (hence the reason for opening a discussion here) regarding how much this segment of the industry is/isn't regulated, but i am reminded of a situation that faced mechanical engineers back at the turn of the last century where in statistically there was one boiler explosion per day within our country (usa). from that debacle came the asme and their boiler and pressure vessel codes that are now adopted (non uniformly i must admit) nation wide and maybe even world wide to some more limited extent.
if the regulation and standardization is as lacking as the drive by news media would have one believe, is it time to arrive at something equivalent for cranes as was done for boilers and pressure vessels?
rmw
it's a good question, rmw and i'm with you about shying away from giving a knee-jerk reaction about what's caused the recent rash of collapses. from where we sit, it's all conjecture, but i think that what you brought up about boilers at the turn of the century may be very relevant to what's going on here.
it's true that boilers were exploding at an astounding rate, but these incidents weren't all attributed to codes, designs or manufacturing. the fact is, captains of steamer ships realized that they could move their ships a whole lot faster if they weren't losing all that steam through that pesky over-pressure relief valve. so, the simple answer was to wire the safety valve shut. it was a "who cares?" attitude -- they didn't own the ship anyway and they could make a whole lot more money by speeding up delivery of cargo. more trips means more money.
and with that, we had the alarming number of boiler explosions that occurred at the turn of the century. but it was less an act of government than it was an act of insurance that corrected this. insurers mandated that any captain or crew caught bypassing a safety device be fired on the spot. insurers alerted shipping companies that they would not underwrite any company that employed those who had bypassed a safety device.
and it makes you wonder. considering how ridiculously difficult it is to fire someone for any level of incompetence, due to the fear of a wrongful termination lawsuit, and considering the breakneck pace of building and construction that has occurred in the past couple of years, what percentage of these collapses will be attributed to design problems and how much will be attributed to a "who cares?" attitude of an operator?
-t
engineering is not the science behind building things. it is the science behind not building things.
in my experience this sort of problem exists because of the "hurry, hurry" attitude of the contractor fostering this same "hurry, hurry" attitude in the operating personnel along with the "all looks good to me, wink, wink" by the building inspector. combine that with the hurry, hurry, time is money, never mind experience, you'll get plenty of it on the job, work for less, hired help. instant recipe for disaster. the existing osha regulations more than likely cover this failure that, most probably, will fall into one of two categories, mechanical failure (always a distinct possibility that is difficult to avoid...a "zero defect" program is just not viable in the construction industry) or human error. human error is of course always a possibility but to blame it on a "who cares" attitude of the operator is overstating the case...most likely a "didn't know it would do that" or some other lack of training, supervision or, experience issue came into play.
the "other" possibility is that due to some failure along the line other than the crane operators is also a good possibility. e.g., my personal experience with
around 1994, the company i worked for, at the time, contracted for the crane, set it up, worked it and, tore it down at the chevron refinery in el segundo. a few months later at the ultramar refinery (ex mcmillan refinery) in the long beach/wilmington area, the same crew set up the same rig and "dropped" it out over a highway bridge under construction while maneuvering it into position for a lift. it was determined that the ground prep was "rushed" and subsidence under one of the tracks caused the collapse. the "hurry, hurry" factor?
rod
agree with everybody here about jumping to conclusions, but collapses of these big cranes seems to be an epidemic. not just in the us either. there have been a couple of recent accidents without injury in brisbane. i think that pressure of time is always involved. with so much construction activity around the world, the availability of experienced crane designers, erectors, and operators is probably very limited.

the crane was one of their designs, versa crane. the model mentioned was the 2400. here is a link to their literature on said crane.
unauthorized reproduction or linking forbidden without express written permission.
my guess would be that some of these links might have better up close info than the bbc - no disrespect meant for the bbc (in this case anyway.)
now i will come back and post a comment.
i don't tend to run with the knee jerk crowd that always wants to overact to any slow news day spectacular of the day but the constant drumbeat of crane disasters is beginning to be troubling.
i don't know the facts (hence the reason for opening a discussion here) regarding how much this segment of the industry is/isn't regulated, but i am reminded of a situation that faced mechanical engineers back at the turn of the last century where in statistically there was one boiler explosion per day within our country (usa). from that debacle came the asme and their boiler and pressure vessel codes that are now adopted (non uniformly i must admit) nation wide and maybe even world wide to some more limited extent.
if the regulation and standardization is as lacking as the drive by news media would have one believe, is it time to arrive at something equivalent for cranes as was done for boilers and pressure vessels?
rmw
it's a good question, rmw and i'm with you about shying away from giving a knee-jerk reaction about what's caused the recent rash of collapses. from where we sit, it's all conjecture, but i think that what you brought up about boilers at the turn of the century may be very relevant to what's going on here.
it's true that boilers were exploding at an astounding rate, but these incidents weren't all attributed to codes, designs or manufacturing. the fact is, captains of steamer ships realized that they could move their ships a whole lot faster if they weren't losing all that steam through that pesky over-pressure relief valve. so, the simple answer was to wire the safety valve shut. it was a "who cares?" attitude -- they didn't own the ship anyway and they could make a whole lot more money by speeding up delivery of cargo. more trips means more money.
and with that, we had the alarming number of boiler explosions that occurred at the turn of the century. but it was less an act of government than it was an act of insurance that corrected this. insurers mandated that any captain or crew caught bypassing a safety device be fired on the spot. insurers alerted shipping companies that they would not underwrite any company that employed those who had bypassed a safety device.
and it makes you wonder. considering how ridiculously difficult it is to fire someone for any level of incompetence, due to the fear of a wrongful termination lawsuit, and considering the breakneck pace of building and construction that has occurred in the past couple of years, what percentage of these collapses will be attributed to design problems and how much will be attributed to a "who cares?" attitude of an operator?
-t
engineering is not the science behind building things. it is the science behind not building things.
in my experience this sort of problem exists because of the "hurry, hurry" attitude of the contractor fostering this same "hurry, hurry" attitude in the operating personnel along with the "all looks good to me, wink, wink" by the building inspector. combine that with the hurry, hurry, time is money, never mind experience, you'll get plenty of it on the job, work for less, hired help. instant recipe for disaster. the existing osha regulations more than likely cover this failure that, most probably, will fall into one of two categories, mechanical failure (always a distinct possibility that is difficult to avoid...a "zero defect" program is just not viable in the construction industry) or human error. human error is of course always a possibility but to blame it on a "who cares" attitude of the operator is overstating the case...most likely a "didn't know it would do that" or some other lack of training, supervision or, experience issue came into play.
the "other" possibility is that due to some failure along the line other than the crane operators is also a good possibility. e.g., my personal experience with
agree with everybody here about jumping to conclusions, but collapses of these big cranes seems to be an epidemic. not just in the us either. there have been a couple of recent accidents without injury in brisbane. i think that pressure of time is always involved. with so much construction activity around the world, the availability of experienced crane designers, erectors, and operators is probably very limited.

the crane was one of their designs, versa crane. the model mentioned was the 2400. here is a link to their literature on said crane.

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