Only a USCG license? That thing looks like the bottom part of a flight simulator.
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Have you looked at the number of sheaves there are in the hook block on a 2000 m.t. SWL crane?
FYI;
Active Heave Compensated cranes are single line and with far smaller SWL:
Whatâs that got to do with the price of rice?
Nothing, but it do have a lot to do with the ability to make a crane AHC.
Have you seen how many parts on a drawworks traveling block that is heave compensated by the motor drives? Looks the same. Nothing wrong with building a platform with associated hydraulics and PLCs etc to control. Good marketing video. God bless them. Merely suggesting there could be an alternative for the other end of the rigging. An alternative that might allow use of more varied shuttle vessels not requiring a special platform on each.
I have. The NOV AHC drawwork weight in at 90 m.t. and the Hitech one at 80 m.t.
Not very suitable for a revolving crane.
OMG seriously? You think Iâm suggesting mounting a full scale drawworks on a crane? Think scalability. Winch drum driven by gearboxes, motors, drives sized for the job. This conversation has run its course. First you said it canât be done because a crane has multipart falls, then because a NOV drill ship drawworks weighs too much. Iâm out. Talk to yourself for a while.
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Lotta sniping going on here by supposedly bright folks. As the OP said, here we go again.
So obviously the Engineers at Appleman and Huisman are some stupid squar-headed Dutchmen that know nothing about motion compensated cranes and drawworks?
Perhaps I misunderstand, but I donât think that would do the same thing. Heave compensating the crane is one thing. Setting the target of said compensation to the barge deck is another, which seems like it would entail some technical challenges. If you achieve that, you still have pitch and roll to contend with. I can easily imagine some large and fragile assembly getting bumped by a pitching deck in the moments after load is transferred to the crane.
If the lifting operation is delicate enough, I think you need both a motion compensated load platform and a heave compensated crane, to avoid operating within a narrow weather window.
Even that scenario doesnât account for the risk of striking nearby structures after the first few feet of lift. Once the crane takes the load off the compensated platform it is exposed to motion of the structure that platform is mounted on and the independent motion of the crane vessel. How fast and how far can the crane take the load and how much acceleration can the load and crane sustain without damage?
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In this case the crane vessel is jacked up above wave action, so steady.
But lifting say the Nacell from the deck of the floating transport vessel while the tall transition pieces are still standing upright on her deck could be a challenge.
PS> Heave compensated cranes on rigs and fixed platform has existed since the late1970s
[quote=âombugge, post:92, topic:59027â]
But lifting say the Nacell from the deck of the floating transport vessel while the tall transition pieces are still standing upright on her deck could be a challenge.[/quote]
Is there an echo in here?
Is there anyone on this site who is not aware of that?
Ah this very thought occurred to me during my morning toilette. And this is the sort of response I was expecting as opposed to the sputtering, spitting poppycock in so ample supply lately.
Keeping the base of the load parallel to the sea surface would help at lift off and combined with the heave compensated crane winch would seem to set it up nicely. But as Steamer points out what happens then? Iâm thinking the answer is not to be found in press releases but in practice and with operational limit windows. Is the cost of this device offset by the increase in the operational limits at which lifts can be made? In other words is the cost offset by increased productivity? I have no idea. Cute piece of machinery. Looks like potential overtime and parts requisition generator but again maybe you can only turn it on within a specific set of environmental conditions so it doesnât shit itâs britches. Reminds me of the Sulzer RTA mounted PTO / hydrostatic transmission / âshaftâ generator rig on my first Chiefs job. Off more than on. I wasnât trying to say it is necessarily a bad idea just tinkering with the concept.
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The article was full of the PR speak that we are so often beaten over the head with. If we monitor everything endlessly it always doesnât follow that slinging a turbine blade offshore is going to go smoothly.
I can see that a lot of expertise and equipment developed over the years in the offshore oil industry is equally applicable to installing turbines but having no knowledge of turbines I will just keep reading.
Having said that, it has been an entertaining read gentleman, and others, and at times given me a bloody good laugh.
Biden said it, windmill blades are going to be made in the USA not China
I am up in the NE now during survey work for windfarms. First time in 25 years my paycheck hasnât come from the Gulf of Mexico. Kind of windy and rough up here but this wind is the reason for the windfarm. Anyways I donât post on here much but the beginning of this thread started on the Jones act and Mariners jobs, but the Mariners were quick to throw out reflagging foreign vessels as an option to allow for US Mariners to work on appropriate vessels for the job. This throws the other component of the law that protects the shipyard workers under the bus. Not starting a war, just pointing it out.
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How steady is that work and for how long? Feel free to PM me if youâd rather. Just curious myself.
No one is âthrowing shipyards under the busâ.
Allow temporary reflagging of a small number of wind vessels, until shipyards can build new wind vessels.
Alternatively pause offshore wind construction until shipyards can build the new vessels.
Otherwise cancel the whole damn scheme of high cost heavy subsidized extra electricity that we donât really need and that isnât creating American jobs.
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