Combustion Vibrators

Petrol concrete vibrators — how they work

A petrol vibrator is an internal (immersion) vibrator. Its working part is the vibrator head, also called a poker — a steel cylinder with an eccentric weight, lowered straight into the fresh mix. Spinning at roughly 10,000 rpm, it liquefies the concrete for a moment so that trapped air can rise. The difference from mains-powered models is the drive: instead of a cable and a frequency converter, a four-stroke petrol engine, usually a Honda GX 35 or GX 50 of about 1.3–1.6 hp.

Such a set starts anywhere on site, with no cables and no voltage drop. The trade-off is exhaust fumes, so indoor work in halls and basements is better served by 230 V vibrators or 42 V / 200 Hz vibrators.

Vibrating lance, backpack or flexible-shaft drive

Where the engine sits decides the operator's reach: on the pole in a vibrating lance (Enar VIB-BAR, Toolsa Power-Bar), on a back-worn frame in a backpack vibrator (Enar Back Pack, Beton Trowel HDBP35H), or in a separate ground-standing drive unit (Altrad Belle BGA).

• Vibrating lance — shaft about 0.5 m, around 16 kg; strip foundations, ring beams, pad footings.
• Backpack unit — flexible shaft about 2 m, 12–16 kg on the back; slabs, floor decks, longer pours.
• Separate drive unit — hose up to 5 m, heads 25–68 mm; walls, columns, precast.

Matching head diameter to the structure

Head diameter sets the radius of action — the zone within which concrete is genuinely compacted — and with it hourly output. The denser the reinforcement and the narrower the formwork, the slimmer the head. Petrol sets compact up to 25 m³ per hour.

Heads are wear parts — aggregate abrades the casing. Replacements sit under vibrator heads; all drive options are under concrete vibrators.

Brands and working technique

Spanish Enar builds VIB-BAR lances on Honda GX 35 and GX 50 engines, plus Back Pack sets with 40 and 45 mm heads. British Altrad Belle supplies BGA drive units that take 25, 45, 55 and 68 mm heads and run at roughly 187 Hz, while Beton Trowel offers the HDBP35H backpack unit. Toolsa adds the Power-Bar with its 35.8 cm³ engine, alongside equipment from Husqvarna Construction.

Lower the head quickly and vertically, withdraw it slowly, and when pouring in layers push it 10–15 cm into the layer below so the two bond. The costliest mistakes are over-vibrating, striking the reinforcement and pushing the mix sideways. The surface is then levelled with vibratory screeds, and formwork compacted from the outside with external vibrators.

Frequently asked questions about petrol vibrators

Why buy a petrol concrete vibrator at NORWIT.PL

We match the set to the job: head diameter to the reinforcement, shaft length to the formwork, drive layout to the crew. The range covers professional Enar, Altrad Belle and Beton Trowel equipment, with replacement vibrator heads and wear parts. Orders are placed online and shipped throughout Poland.