These concrete vibrators are also called poker or immersion vibrators. These are widely used in the construction industry. A needle vibrator consists of a cylindrical casing made of steel and vibrates with an outer tube driven to an operating machine by means of a flexible drive that can be propelled by electricity, petrol, diesel or compressed air. The frequency of vibration of an immersion vibrator is very important because higher frequencies give better compaction. it differs from 3500 to 12000 cycles per minute, Frequencies below 3500 cycles per minute are inefficient for concrete compaction. Diameter Vibration varies from part to part 20 to 75 mm and his Length Changes 25 to 90 cm,
Needle vibrator machine
how to use needle vibrator
Following points are important for efficient use of needle vibrator.
While pouring the vibrator into the freshly laid concrete, we should keep it upright and drop it slowly at an angle. This method will vibrate over a large area.
While pouring the vibrator into the freshly laid concrete, we should keep it upright and drop it slowly at an angle. This method will vibrate over a large area.
Pull out the vibrator slowly so that the hole is filled. It is also necessary to limit the starting distance of the vibrator to less than 45 cm (18 in).
We should not vibrate the formwork with needle vibrator as it will damage the formwork. We should place it only 75 mm (3 inches) away from the formwork.
While depositing the concrete on top of the second layer already laid, we should push the vibrator a short distance (about 75mm) into the already laid fresh lower layer to join the two concretes together.
The depth to which the vibrator can be immersed is limited by the position of the flexible drive. The vibrator head can be let down to the point of flexible drive in the concrete.
Do not leave the vibrator on when it is not on concrete. Otherwise it may overheat and the bearing may break.
When setting fresh concrete, the entire permissible length of the vibrator is inserted into the concrete. This step is necessary to keep it from overheating. Immersion in concrete cools it.
Avoid sharp turns of the flexible drive, especially on the vibrator head. Otherwise a lot of pressure is put on the outer tube and the inner flexible drive.
The amount of concrete that can be vibrated by a vibrator per hour varies from 4 to 30 m3 depending on the vibrator and the method of placing the concrete.
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