The strength of reinforced concrete structures depends on the formulation and the quality of the mortar. The technology of pouring concrete is to compact the mixture to remove air bubbles that turn into pores when solidified. To facilitate the process, depth and platform vibrators of various types are used. These devices allow pouring durable reinforced concrete structures that meet quality standards.
Application area
The scope of surface-type machines is quite wide, they can be used to compact liquid solutions and bulk materials, dehydrate food products, and unload bins. The mechanization of the main and auxiliary processes in the construction of buildings and roads, the production of bricks and paving slabs - this is the scope of areal vibrators. The device is operated with a ramming board or vibrating table - depending on the conditions.
Purpose and principle of operation
Vibratory compactor for concrete reduces the porosity of the hardened product by displacing air from the mixture. The second function of the device is shaking with the aim of penetrating the solution into the cracks and gaps of the cast structure to increase strength. The principle of operation of any type of vibrator is to unwind the eccentrics located on the shaft of the induction motor. The oscillations of the shaft caused by the conversion of electrical energy into mechanical energy are transmitted to the vibrator body, and then to the concrete.
For an external or surface type surface vibrator, a wooden or metal shield is laid on the solution layer, transmitting vibrations to the solution from the device body. The scope of machines mounted on the shields is the shaking of concrete mortars of any type in structures with dense reinforcement, where the operation of a deep vibrator is impossible.
Surface vibrator design
The device of the platform vibrator is universal for any model and brand. This is a sturdy case with a built-in electric motor, on whose shaft eccentrics are mounted to shift the center of gravity. Fluctuations that occur when the motor rotates are transmitted to a bolted plate or table. The vibration seal can be supplied with a gasoline engine for use in places where there is no electricity.
Having a similar device, different models differ in design. Some models are sold in the form of an enclosed electric motor, others with an attached metal plate and handle for holding the vibrator, protective cast-iron shields, and so on.
The simplest design is cheap household machines designed for a short life and home construction. More expensive vibration seals are equipped with prefabricated metal shields, presenting the finished device, ready for use.
Depending on the type of work performed, the vibrator is attached to the table, molding cartridges for the production of bricks or paving slabs, metal plates or to the metering dampers of bins for bulk materials.
Main characteristics
Technical characteristics of platform vibrators depend on the purpose of the device: domestic or professional. According to the electric motor power, the vibrators are divided into household, semi-professional and professional. The electric motor power of the first is 0.2-1 kW, the second is 1-10 kW, and the third is up to 24 kW. Household surface vibrators are designed for a supply voltage of 220 V and a frequency of 50 Hz. The rest work with different rated supply voltages - 42 and 380 V, designed for a power grid frequency of 50-200 Hz.
The second important characteristic of the platform vibrators is the driving force causing vibrations. It varies from 200-400 N to several tens of kN and depends on the mass of the eccentrics and the frequency of rotation of the motor shaft.
Surface vibrators are quite massive devices, even for domestic use. Their weight is several kilograms, and the weight of professional is measured in tens of kilograms.
The performance of the tamping process depends on many parameters of the vibration compactor, but the main ones are the weight, power and driving force, which are guided by when choosing.
Marking vibrators
Household site vibrators are marked with the letter “E” regardless of the model name, which means the frequency of the supply voltage is 50 Hz. The vibration seals, marked with the letters “A” and “B”, are made of ordinary components using standard parts. These machines are suitable for small-volume operations, since their operating time is up to 900 hours.
Expensive vibrators are marked with the letter “H”, which means increased protection against dust and moisture. Such vibration seals are assembled with additional protective covers, shields, and the winding of the electric motors can be double impregnated. The service life of machines marked with the letter “H” is increased at least three times.