What Is an Internal Concrete Vibrator?

The Internal Concrete Vibrator compacts fresh concrete directly inside the mould. The vibrating poker is inserted into the concrete and transfers mechanical vibration throughout the surrounding mix. As a result, the concrete moves more easily and fills internal spaces within the mould.

Proper compaction has a direct effect on the quality of concrete test specimens. Insufficient vibration may leave air voids inside the specimen. Therefore, internal vibration provides laboratories with a practical method for preparing dense and more uniform concrete samples.

Different Poker Head Options

The product range includes four different poker head diameters. Users can choose between Ø32, Ø38, Ø45 and Ø50 mm depending on the mould dimensions and concrete mixture.

Smaller poker heads provide easier access in narrow moulds. Larger heads, on the other hand, create a wider vibration zone in larger specimens.

However, the poker head should not strike the mould walls or reinforcement during operation. Correct positioning helps maintain controlled compaction and protects the test equipment.

High-Speed Vibration System

The LT-C0045 operates at 12,000 rpm. The LT-C0046, LT-C0047 and LT-C0048 models operate at 18,000 rpm.

All models include a 4 m flexible shaft. The long shaft gives the operator greater freedom when working with deep moulds or specimens positioned away from the drive unit.

In addition, the flexible construction allows the vibrating head to move through the concrete in a controlled manner.

How Is Fresh Concrete Compacted?

First, the operator fills the mould with fresh concrete in the required layers. The poker head is then inserted vertically into the concrete.

The operator should move the vibrator between suitable locations rather than keeping it in one position for an excessive period. During vibration, entrapped air rises toward the surface and the concrete settles within the mould.

When large air bubbles decrease and the concrete reaches suitable compaction, the operator slowly withdraws the vibrating head.

Excessive vibration may cause segregation in some concrete mixtures. Therefore, vibration duration should be selected according to the concrete consistency, specimen dimensions and applicable test procedure.

Compact and Portable Design

Each model weighs approximately 6.5 kg and has overall dimensions of 40 × 16 × 24 cm. This compact structure makes the unit easier to move within the laboratory and transport to suitable field applications.

The system operates on 220 V, 50–60 Hz, single-phase power. Therefore, it can be connected to standard laboratory electrical supplies where compatible.

Concrete Specimen Preparation According to Standards

EN 12390-2 covers the preparation and curing of concrete specimens for strength testing. The standard includes requirements related to mould filling and specimen compaction.

In addition, ASTM C31/C31M covers making and curing concrete test specimens in the field, while ASTM C192/C192M addresses laboratory preparation and curing procedures.

The product range also references AASHTO T23 and AASHTO T126 for relevant concrete specimen preparation applications.

Reliable Internal Concrete Compaction

The Internal Concrete Vibrator combines different poker head diameters, a long flexible shaft and high operating speeds in one practical product range.

As a result, laboratories and field teams can select the appropriate model for their mould size and concrete mixture. The system provides a practical solution for preparing well-compacted, homogeneous and repeatable fresh concrete test specimens.