What types of heavy machinery are there and what is each one for?

Seven jobs, seven families

Before looking at models, ask what job the machine will do most of the time. That answer gives you the family; size comes later, based on volume and space.

Excavator: the one that does the most jobs

The excavator swings 360° on its undercarriage and works with a boom, arm and bucket: it opens trenches, digs footings and basements, loads trucks and, with a hydraulic breaker, demolishes. You choose it by operating weight (the 20-tonne class is the most common in civil works), by tracks or wheels, and by the reach your job needs.

In Grupo ConstruMarket's catalog, Komatsu excavators run from the PC130-8 to the PC1250-11R, in all four countries. For urban work and tight spaces there are Bobcat mini excavators (E10 to E80) in El Salvador and Panama.

• How to choose an excavator (and what size you need)
• How many cubic meters per hour does an excavator move? How to calculate productivity
• How to choose the right excavator bucket

Backhoe loader: two machines in one

The backhoe loader has a loader in front and a digging arm in the back, on wheels. It digs medium trenches, loads, backfills and drives on the road from one job to the next without a trailer. That's why it's the machine of municipalities, urban work and contractors who do a bit of everything. What it doesn't do is match an excavator in output or digging depth.

Grupo ConstruMarket offers the Komatsu WB93R-5E0 and WB97R-5E0.

• How do you choose a backhoe loader for your jobsite?
• Mini excavator or backhoe loader: which one is right for you?

Wheel loader and skid steer: the loaders

The wheel loader picks up loose material with its bucket and carries it to a truck, a hopper or a stockpile: sand, gravel, aggregates, soil. It's the machine of yards, quarries, concrete plants and any job where loading goes on all day. Komatsu runs from the WA150-5 to the WA500-6 in the catalog.

The skid steer is its compact version: it turns on the spot, goes where the loader can't fit and changes job by changing the attachment (bucket, forks, breaker, sweeper, auger). Bobcat in El Salvador and Panama; Komatsu SK820-5E0 in Guatemala and Nicaragua.

• How to choose a wheel loader and what drives its price
• How do you choose a skid steer: radial or vertical, wheels or tracks?
• Which skid-steer attachment should you use for each job?

Dozer: the one that pushes

The dozer, or crawler tractor, pushes large volumes of soil with its blade and, with the ripper at the back, breaks hard ground or soft rock. It opens roads, clears land, shapes embankments and spreads fills. Its tracks spread the weight so it can work on soft ground or slopes where a wheeled machine slips. Over short push distances it's unbeatable; to move material far, load trucks instead.

Komatsu runs from the D39EX-22 to the D275AX-5E0 in the catalog.

• When does a bulldozer make sense?
• Heavy machinery for earthmoving: which machine for each task?

Motor grader: the one that sets the grade

The motor grader cuts and spreads thin layers with a long blade between its axles: it shapes roads and streets, levels pads, cuts ditches and maintains dirt roads. It's the precision machine of earthworks: it doesn't move big volumes, it leaves the surface at the design level and slope. With 3D guidance, it does it in fewer passes and with less surveying on site.

Komatsu runs from the GD535-5 to the GD705-5 in the catalog.

• What is a motor grader and how do you choose the right one?
• What is road infrastructure (vialidad) and what machinery does a road job need?
• What is 3D machine guidance and when does it pay for itself?

Rollers and paving equipment: the ones that compact and finish

The roller compacts what the other machines left loose. Soil rollers (smooth or padfoot) densify bases, sub-bases and embankments; asphalt rollers (tandem or pneumatic) compact freshly laid asphalt. Good compaction is what keeps a street or a pad from sinking in the first rainy season.

In El Salvador and Guatemala, Grupo ConstruMarket distributes BOMAG: soil and asphalt rollers, pavers, cold planers and recyclers. In Nicaragua, Dynapac rollers. For small areas and trenches, light compaction equipment (rammers and plates) is SIMAQ, in all four countries.

• Types of compactor: which one to use for your soil? (rammer, plate or roller)
• What equipment do you need to build a road? Machines by phase

Trucks and dumpers: the haulers

Moving material is often the costliest part of a job. The rigid off-highway truck carries big loads on firm haul roads and is the standard in quarries and mines; the articulated truck bends in the middle and keeps moving in mud, on slopes or soft ground. For short distances inside the site, the dumper with a front skip.

The catalog includes Komatsu HD325, HD405 and HD465 rigid trucks, the HM400 articulated truck, and D'Avino dumpers in El Salvador and Guatemala.

• Articulated hauler or dump truck: which one fits?
• What machinery is used in mining and how do you choose it?
• How is heavy machinery transported?

Telehandler and forklift: the lifters

The telehandler lifts and places loads up high and forward with a telescopic boom: block, steel or pallets on the second floor of a job, or bales and sacks on the farm. The forklift moves pallets on firm floors, in a warehouse, yard or plant.

Bobcat telehandlers in El Salvador and Panama; Hangcha forklifts (electric, combustion and rough-terrain) in all four countries.

• What is a telehandler (telescopic handler) and when does it make sense?
• Which forklift do I need: diesel, LPG or electric?
• Forklift vs. skid steer: what are the differences and which do you need?

Which combination your job needs

Almost no job gets done with a single machine. Think about the flow of material: who digs it out, who loads it, who hauls it and who leaves it finished. If one machine sits waiting on another, your fleet is the wrong size, even if every machine is good.

If you only need a machine for a few weeks, renting may beat buying; if it will work every day for years, compare the cost per hour of owning it.

• Rent or buy machinery? How to decide with numbers
• How do you calculate a machine's cost per hour?
• Excavator brands in Guatemala and Central America: how do you compare them?

Heavy or light machinery: where the line is

There's no official boundary, but on site heavy machinery means machines with a diesel engine, a cab or ride-on operator, that move soil or loads in volume: everything in this guide. Light equipment is what you run on foot or carry in a pickup: rammers, plate compactors, concrete mixers, concrete vibrators, saws, water pumps and light towers.

At Grupo ConstruMarket, light equipment is SIMAQ, the group's own brand, plus Wacker Neuson in El Salvador and Guatemala. The how-to guides for light equipment and concrete live in the SIMAQ School (simaq.pro/aprende).

• How do you choose an electric generator for your jobsite?
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