A compactor is a machine designed to reduce the size of a material or biomass through compaction. Roller compactors operate in a simple, yet effective, way. The weight of the compactor is the driving force of the compaction, while the drum of the compactor ensures an even distribution of weight when moving either forwards or backwards.
Other types of compactors are powered by hydraulics and are built with engineering techniques that allow them to increase their payload of material and thus reduce the number of times they have to dump. Some of these compactors are used as trash compactors, car crushers and road rollers.
When deciding what size compactor to get, you have a lot of factors to think about. This includes the material you’re working with, it’s volume, your real-world operating hours and how your site is organised. Before you even choose the size, you have to think about choosing the type! This blog will walk you through how to choose the right size compactor for you.
Step 1: Have a look at what you’re compacting
Depending on the material you are compacting you may be required to hire different compactors. Here’s what compactor you should be looking at depending on your material:
- Cohesive soils (clay, silt): vibrating compactors such as padfoot rollers
- Granular soils (sand, loam, gravel): smooth drum rollers or pneumatic rollers
- Landfill: waste compactors
- Crushed rock: roller compactors
- Small Backfill and compaction: rammer compactors
Step 2: Calculate how much material you need compacting
When you’re looking at a roller compactor the weight of the material means just as much as the area you’re rolling it in. You’ll want a roller that can complete the job in the fewest passes possible and with minimal overlap in-between. Walk-behind rollers, rammers and vibrating plates are best for compacting in a tight space such as a footpath.
Choosing a roller compactor also depends on the depth of the material. Vibrating rollers are generally better for deeper soil than pneumatic rollers. Here’s a simple guide to roller size vs soil depth (this applies to soil):
- 7 tonnes: up to 150mm
- 15 tonnes: up to 300mm
- Over 15 tonnes: over 300mm
When looking at trash compactors, however, you should be thinking about weight. Assuming a perfect world where you’re running your compactors constantly with a consistent workflow, here’s a basic guide to how big your compactor should be depending on the weight you’re compacting:
- 23-27 tonne compactor: up to 300 tonnes
- 28-32 tonne compactor: 200-600 tonnes
- 36-40 tonne compactor: 300-900 tonnes
- 45-47 tonne compactor: 700-1500 tonnes
- 50-57 tonne compactor: 1100-2600 tonnes
You’ll notice trash compactors are much bigger than roller compactors. Again, keep in mind that what you’re compacting determines what size compactor you’ll need – trash is much harder to compact than soil, and you’re usually compacting much more of it at a time, so take that into account.
Step 3: Check what your peak operating hours are
On a standard job site, it’s typical that you’re not going to get a consistent flow of the same amount of material coming in to compact. So, if you already own a compacting business, have a look through your records and record your peak times and low points. If not, do some research into when your potential customers might come in and try to estimate the peak times and low points from that.
Consider how your site is organised, especially if you have the capacity to set aside material to compact later. How much of it can you set aside? For how long? Take this into account when deciding what size compactor to get; you’ll want to balance being able to keep up with your work during peak times and not having too much downtime spent running a large compactor with not much to compact.
Choose your compactor size and hire with EPH today
Once you have taken into account the material you’re compacting, the type of compactor you’ll need, the weight or surface area that you’re compacting and planning out how you’ll manage shifts in peak and low periods, it’s time to hire your compactor! Eastern Plant Hire has roller compactors available for whenever you need. Contact us today to hire it out.