Mobile crane vs crawler crane for tight urban jobs - which way do you lean?

I keep seeing guys bring a 90-ton crawler into a downtown Detroit site when a 50-ton mobile with outriggers would do the same job in half the setup time. But then the crawler guys argue they don't need mats or worry about soft ground as much. Last week this debate got heated on a job near Campus Martius when a mobile crane had to reposition 4 times because of sewer lines. I'm starting to think the right choice depends more on the ground conditions than the lift weight. Anyone have a rule of thumb they stick to for deciding between the two?

3 comments

3 Comments

riverreed12d ago

You're overthinking this. Crawlers win every time in tight urban spots because they don't need to spread out like mobile cranes do. Those sewer lines you mentioned? That's exactly the problem with outriggers. You're one utility strike away from a lawsuit. A crawler just rumbles over the whole mess and sets up right where it needs to be. Plus half those "soft ground" issues on urban jobs are actually vaults and buried debris, not soil. I've seen a 70-ton crawler walk right over an old brick sewer that would have caved under a mobile crane's outrigger pad. If you're worried about setup time, you're probably not accounting for all the time you waste getting the utility locates done and fighting with the city.

mark_thomas5d ago

Riverreed makes some good points but I've got to push back a little. @victor_adams mentioned ground conditions and I think that's really the heart of it - that old brick sewer he walked over might have held fine, but I've seen a 50-ton crawler sink right through asphalt that looked solid but had a buried cistern underneath. It's not just about whether the crawler can handle the surface, it's about what's underneath that you can't see. Maybe it's just me but I've spent too many days waiting for a tow truck after a crawler found a soft spot to ever trust them completely in unknown terrain.

victor_adams12d ago

Ground conditions decide it every time, no point arguing about setup speed when you're dealing with buried utilities.

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