Why does SpaceX use a Liebherr 11350 rather than a Tower Crane

[jamescobban]

One thing I am puzzled about is why SpaceX chose to purchase an expensive LR 11350 for moving stuff around the launch pad, rather than a much cheaper tower crane mounted on top of the Launch Tower.  Similarly it seems to be that a lot of the movements of equipment and supplies around the construction site could be performed more easily with a tower crane than the various mobile cranes.

[AS_501]

I'm guessing that a permanent crane would be more costly than a portable crane like Liebherr 11350.  A permanent crane would require its own power feeds on the tower, lightning protection, weatherproofing, etc., plus some repairs after being blasted by SH's exhaust.  One the other hand, a transportable crane can be called up only when needed, then broken down and put into protective storage until needed again.

I think it was Jim who said the Saturn V LUT hammer head crane was largely useless. If something like the Liebherr crane had been available in the 1960s, the LUT crane may not have been needed.

PS:  Welcome to the Forum!

[Alvian@IDN]

The crane on the launch tower already exists, it's called "chopsticks", but it's only designed to lift the ship (& later booster)

Chopsticks obviously is limited in place, and the launch site area is large, so they used a crane

I'm still not sure why they opted to buy, rather than just renting a crane tho

[nacnud]

SpaceX doesn't know what they are doing, sorry I mean they can't know what they will do. They are iterating so fast and changing plans so much that a crawler crane is probably cheaper than moving a tower crane when plans change, which they do, often.

Using a static tower crane to save costs is optimising for cost before knowing what you are actually building.

See Elons 5 step engineering principles https://cleantechnica.com/2021/08/16/elon-musk-reveals-his-5-step-engineering-protocol/

[Lee Jay]

One thing I am puzzled about is why SpaceX chose to purchase an expensive LR 11350 for moving stuff around the launch pad, rather than a much cheaper tower crane mounted on top of the Launch Tower.  Similarly it seems to be that a lot of the movements of equipment and supplies around the construction site could be performed more easily with a tower crane than the various mobile cranes.

Tower cranes tend to be pretty weak (low lifting capacity). Many are in the 10-20 ton range, which is way too low for most of their lifts. Plus, they are very inflexible compared to a mobile crane. These are the reasons they tend to cost a lost less - because they lack features (tracks, strength, etc.) which means they can do a lot less.

What they can do is be supported by the tower that they are building, which means their height can be limited only by the structure being built.

[guckyfan]

I'm still not sure why they opted to buy, rather than just renting a crane tho

They had a rented big crane. Every time they did somethin risky they removed it, a time consuming thing to do. I have speculated they can just take the risk with their own crane. But not with a rented crane and the requirements for insuring it.

[seb21051]

I was under the impression that the new crane is a Liebherr 11100. They had a 11350 earlier on that they were renting, but sent it back once they got the 11100. The 11350 was an older design that was not as easy to move around. The reason they have a mobile is because they have jobs that require it to move all over the launch area, such as for GSE as well as the rockets.

[Robotbeat]

How much does one of these things cost to buy?

[daavery]

frankencrane was an LR11350 ( 1350 T max lift), the new crane is an LR11000 (1000 T Max lift)

Leibherr crane numbers are a "1" plus the lift capacity in metric tons

[Robotbeat]

frankencrane was an LR11350 ( 1350 T max lift), the new crane is an LR11000 (1000 T Max lift)

Leibherr crane numbers are a "1" plus the lift capacity in metric tons

How much do they cost to buy, very roughly?

[Lee Jay]

frankencrane was an LR11350 ( 1350 T max lift), the new crane is an LR11000 (1000 T Max lift)

Leibherr crane numbers are a "1" plus the lift capacity in metric tons

How much do they cost to buy, very roughly?

The better part of $10M, depending on accessories.

[whitelancer64]

frankencrane was an LR11350 ( 1350 T max lift), the new crane is an LR11000 (1000 T Max lift)

Leibherr crane numbers are a "1" plus the lift capacity in metric tons

How much do they cost to buy, very roughly?

"As of 2018 the LR 11350 is still produced, with a list price between €7,953,000 and €10,122,000."

https://www.lectura-specs.com/en/model/cranes/crawler-cranes-lattice-boom-liebherr/lr-11350-1049556

[Robotbeat]

So by using Stage Zero, SpaceX saves the purchase price of a $10 million crane.

[tgr9898]

So by using Stage Zero, SpaceX saves the purchase price of a $10 million crane.

Considering all the extra pieces they fitted to Frankencrane (giving it that name), I suspect they saved more than that.

[Bob Niland]

Keep in mind that this crane likely has excellent resale value, if Sx finds they don't need it later on. It might even be cheaper to own&resell vs. lease. The resale value of much of the other site infrastructure ranges from OK to scrap.

[tgr9898]

Two additional thoughts -

Renting a big crane isn't like renting a car - there's a lot of scheduling and transportation issues that surround the rental period.  And there are other customers interested in renting that same crane.  Sometimes a longer rental period doesn't lower the cost (the opposite even) since the supplier has other potential customers. Given how much SpaceX changes plans, it probably got to the point where it was simply cheaper and faster to own the crane than to keep extending the rental of the original.

Additionally, the Liebherr crane they bought can be used however they want.  Say the FAA decides to approve the launch license tomorrow and SpaceX gets Stage Zero done over the next three months. The crane they want can be moved to KSC or Vandenburg to help build out additional stage Zeros.  Or onto the oil platforms, too.  Alternatively, if the FAA says that the environmental concerns are so great that it's going to need 2 years of remediation.... the purchased crane could leave B.C. tomorrow... 

[edzieba]

There are also lead times: Liebherr don't just keep a stock of ready-made ultralarge cranes to hand for immediate fulfilment, they're built to order. SpaceX are not ones to sit on their laurels whilst waiting for shipping, hence renting one in the meantime.

SpaceX do in fact have a tower crane (well, technically a column crane) on site. It's been sitting in the shed next to the 'roll lift park' since before even the Stargate building was finished. I'm starting to think they've actually forgotten that it's there.

[danneely]

There are also lead times: Liebherr don't just keep a stock of ready-made ultralarge cranes to hand for immediate fulfilment, they're built to order. SpaceX are not ones to sit on their laurels whilst waiting for shipping, hence renting one in the meantime.

SpaceX do in fact have a tower crane (well, technically a column crane) on site. It's been sitting in the shed next to the 'roll lift park' since before even the Stargate building was finished. I'm starting to think they've actually forgotten that it's there.

I think the bigger problem is that crane was probably only sized for Falcon 9 and just isn't big enough for what they'd doing now