400 kg Soil Compactors

The 400 kg compactor — specifications and working principle

A soil compactor, also known as a vibratory plate, densifies the ground with a vibrating steel plate driven by an eccentric exciter — an assembly of rotating unbalanced masses that turns engine revolutions into vertical vibration of the plate. In the 380–420 kg operating-weight class the centrifugal force is usually 40–60 kN, vibration frequency around 65–80 Hz and the working plate 45–70 cm wide. Together those figures compact a 40–55 cm lift of granular soil in one pass at a travel speed of roughly 20–25 m/min.

Power comes from a combustion engine rated at some 6–9 kW (about 8–12 hp), most often a single-cylinder diesel in this class. The 400 kg machines offered by NORWIT.PL come mainly from Wacker Neuson, Altrad Belle and Bomag.

Why every 400 kg machine is a reversible design

A single-direction plate travels forwards only, so the operator has to swing it round by hand at the edge of the working area. In practice such designs stop at roughly 150–200 kg. A reversible plate carries a twin eccentric arrangement inside the exciter and changes travel direction smoothly, forwards and back, which is why the whole 400 kg segment is reversible. The machine can finish a trench, a ditch or the strip along a foundation wall where it stands, without anyone manhandling a plate weighing close to half a tonne.

The same feature allows compaction on the spot — around manhole bedding and service crossings. The two designs across the remaining weight classes are compared in the categories reversible vibratory plates and single-direction vibratory plates.

The 400 kg class against neighbouring weight classes

Operating weight translates directly into centrifugal force and compaction depth, so the weight class follows the lift thickness specified in the design. The values below are typical for each class — exact figures for every machine are given on its product page.

Where the design calls for lifts no thicker than 40–50 cm, the lighter choice is a machine from soil compactors 300 kg. For embankments and yards measured in thousands of square metres it is worth looking at soil compactors 500 kg. Laying the surface itself calls for lighter machines fitted with a protective mat — see compactors for paving stones.

Which soils a 400 kg machine will compact

Vibratory plates work best on granular soils, where vibration rearranges loose grains into a dense, load-bearing structure. Cohesive soils — loams and clays — transmit vibration poorly, because capillary water binds the clay particles together; a rammer or a roller does a better job there.

Wacker Neuson, Altrad Belle and Bomag in the 400 kg class

This segment is built around manufacturers with an established position in compaction equipment: Wacker Neuson (Germany) — a broad reversible line-up and a hard-wearing exciter; Bomag (Germany, Fayat Group) — specialists in compacting road surfaces; Altrad Belle (United Kingdom) — simpler designs that are easy to service.

Each manufacturer also has its own listing: Wacker Neuson compactors, Bomag compactors and Altrad Belle compactors.

Transport, handling and servicing

At 380–420 kg the machine still fits on a trailer with a gross weight rating of up to 750 kg (payload from roughly 500 kg) — the biggest logistical advantage this class holds over the 500–700 kg segment. Loading is done up a ramp rated for at least 500 kg, with a forklift, or by lorry-mounted loader crane using the factory lifting eye; carrying it by hand is out of the question.

Routine servicing covers checking engine oil and exciter oil, cleaning the air filter and checking V-belt tension. The first service falls after about 20 operating hours, subsequent ones every 100–200 hours. Protective mats, filters and other parts are listed in compactor accessories.

Frequently asked questions about 400 kg soil compactors

Why buy a 400 kg soil compactor at NORWIT.PL

We carry compaction equipment across the full weight range, so we can help match the class to the lift thickness in your design. In the 400 kg segment we offer mainly reversible vibratory plates from Wacker Neuson, Altrad Belle and Bomag, backed by wear parts and protective mats in compactor accessories. Neighbouring classes can be compared in soil compactors 300 kg and soil compactors 500 kg, and the complete overview sits in the soil compactors category. Orders are placed online, with delivery throughout Poland.