- So what are the different type
of overhead crane service classes?
And for your application, how do you determine
what duty cycle that you need?
The good news is we're covering all that and more
in this episode of Cranes 101.
(rock music)
What's up, guys?
Devon here from Mazzella Companies and
today we're covering overhead crane
classification and duty cycle.
In this video, we'll cover what service class means.
We'll cover the different classifications
from A all the way to F.
And then at the end, we'll talk about
how you determine the duty cycle for your application.
So to be honest this video would probably suck
if it was just me standing here,
reading you all the CMAA specifications
for Classes A through F of overhead cranes,
and I would not wanna do that to you,
because I would not wanna watch that video either.
So instead I brought back Chris Whitney, our sales engineer,
to help explain what a service class means.
- Crane service class actually applies more
to the application than it does the crane.
So, when you think about what you're going to be moving,
the material that you're gonna be moving around,
the crane that's lifting it needs to be rated
for the number of lifts per hour
and also the percentage of the capacity of the crane
that is going to be seeing the load.
- What?
- So let's say you have a five-ton crane.
The normal load that you're gonna be lifting
is more in the range of a four-ton or a three-ton.
The percentage again would be 80-60% of the actual
capacity of the crane.
The crane is actually designed to handle
a higher capacity than the actual rated load.
- Oh, okay, so each overhead crane is specifically
designed to lift a certain amount of capacity.
But a quick word of warning on going over that capacity.
- So even though it's rated at a certain capacity,
you don't wanna lift higher than that
because it does have more wear and tear on the crane
and the components itself.
So it's really important to know the application
that you're gonna be placing a crane into.
You don't wanna underspend on a crane
and then find out that it's less than
what you really needed to use it for.
You also don't wanna overspend and break your budget
and have something that is way beyond your use.
- So you might not know this, but there are six
different classifications of overhead cranes to pick from,
and they pretty much break down into three categories.
Bearing life, how many hours you'll get
out of the components,
starts and stops, how many times that motor
can handle stopping and starting,
and then lifts per hour, how many times you'll be able to
pick something up and move it along.
If you're not 100% sure on what overhead crane you need,
take notes on this part.
This is why this video is made, and the more you do now
on your research, the more time and money
it'll save you in the future.
- So the Class A crane, you're basically looking
at a standby crane, it can be used as a backup
in case the main crane goes down
or just for very, very moderate use.
You get 1,250 hours of bearing life,
up to two lifts per hour,
and 75 motor start/stops in an hour.
So you may see these cranes in a motor repair shop
or in a steel mill again as a standby crane
in case the main crane goes down.
These types of cranes won't work in a bigger facility
because the duty cycle is extremely low.
- So how does that differ from a Class B?
- So the Class B duty cycle crane,
you get a little bit more longevity out of the crane.
Bearing life is 2,500 hours.
You get two to five lifts per hour
and also 75 motor start/stops per hour.
Typical use for these types of cranes again
would be like a motor repair shop
that gets a little bit more use.
You'd also see it in light-duty machine shops as well.
So with a Class B crane, it's similar to a Class A crane,
where you don't get a high usage out of it.
It's still a moderate use but it's not standby.
- And a Class C?
- So a Class C duty cycle crane you see
in a higher-use machine shop or
a typical manufacturing facility.
Bearing life, you get 5,000 hours,
for number of lifts per hour you get 5 to 10,
and then with motor start/stops, it is 150 per hour.
A Class D crane is more of a heavier use
than the cranes we've discussed already.
Bearing life is 10,000 hours,
you get 10 to 20 lifts per hour,
and then 300 motor start/stops.
These types of cranes are found
in a heavy manufacturing facility,
such as a construction equipment manufacturer.
So with a Class E crane, this is what you would call
a process crane or something
that is in a severe duty application.
These types of cranes are typically found
in an auto manufacturer or stamping application
where high turnover as well as high usage,
because you get 20,000 hours of bearing life,
you're lifting over 20 times per hour,
and you get 600 motor start/stops per hour.
- So Classes A through E are pretty common
all over the world, depending on the manufacture warehouse
that you're standing in.
However, there is one more type that people
don't usually talk about, and that's the crane Class F
because typically you need somebody to come
into your facility and really recommend it
since it's a higher duty cycle crane
than anything else you've talked about before.
- So the Class F duty cycle crane,
these are constant, severe duty cranes.
So this is the type of application
where you really wanna have a specialist
come in and really determine this is exactly
what you guys need for your application.
- Fortunately, there's a method to this
overhead crane madness, and it comes down to two things,
load class and load cycle.
- So determining the duty cycle of your crane,
you wanna look at the relation of the load class
and the load cycle.
The load class is the relation of the overall capacity
of the crane and the normal load that it sees.
The load cycle is the number of times
that the crane is gonna be used over the life of the crane.
You put these two together and you look at the correlation,
and that'll determine what kind of duty cycle
your crane is gonna see.
- Hopefully this video was able to help you understand
overhead crane classifications as well as the best way
to determine the duty cycle that you'll need.
If you liked this video, definitely check out the rest
of the Cranes 101 series and, while you're there,
consider subscribing to the YouTube channel
so you don't miss out on anything else that we'll be making.
At Mazzella Companies, we have a team
of highly skilled lifting specialists
that want nothing more than to help you save time and money
by giving you good advice on your lifting project,
and they welcome that opportunity.
So if you click the link above,
it'll take you to a resource that we made for you.
It's a 10 Things to Consider When Buying an Overhead Crane
checklist.
It's 100% free, you don't have to spend any money on it,
but it's built with you in mind.
Learning crane classifications, learning duty cycles,
all those things are great,
and this guide is just another tool
to help you on your way to buying an overhead crane.
If you'd like to schedule a consultation
on your next project, please don't hesitate to reach out.
We'd be happy to help you however we can.
Thank you for watching.
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