Generality - Principle - Applications

Flowmeters also called Asameters are instantaneous flow meters suitable for measuring low, medium and high flow rates of any type of fluid in a pipeline. By using suitable materials they are also applicable in the presence of corrosive or acidic fluids or gases, with pressure and temperature conditions contained within the resistance limits of the measuring tube. They are usually formed by a calibrated tube with a raduated scale incised, enclosed at the ends by two plugs that can have male/female threads or flanges for the connection to the pipe. inside the tube there is a float which, moving by being pushed by the instantaneous flow, will be positioned inside the graduated tube and will allow instantaneous flow reading. They are widely used in local measures as they do not need external energy for their operation. They are generally used in water systems, oil, gas, in cooling circuits, heat pumps, heaters, welding machines, transformers, heat exchangers, compressors, chemical industry, pharmaceutical, food, etc ...
The flow switch is a device used to detect a certain flow value of a liquid or gas. Unlike the flow meter, it is not able to make any measurements. the device often has a graduated scale but it is used to set the instrument to the activation threshold value. In fact, the flow switch is used to operate a circuit breaker. Usually an electrical contact of the Normally Open type, Normally Closed or in Exchange mode when a certain flow rate is reached. Find application in control systems, where at project level it is useful or necessary to obtain a change of state for a specific flow value. For example, in heating systems.

Types of flowmeters and flow switches generally on the market:
Variable area flowmeters
Electric adjustable flow switches
Paddle flow switches

The flowmeters are based on the principle of the variable area and therefore on a float suspended in a fluid moving from the bottom to the top, inside a shaped and calibrated tube. The level of the float inside the graduated body depends on the flow rate of the fluid. The scale on the body of the flowmeter is typically designed to measure flow in a 10: 1 range and the flow rate is read at the top edge of the float. Flow meters can measure both fluids and gases, providing a reliable flow measurement in l / h and Nm3 / h.
Main features
- Wide selection of measurement scales
- Wide selection of process connections
- Flowmeter body available in Glass, PA, transparent PVC and PSU (other on request)
- Float available in Stainless steel, PP (other on request)
- Good precision and high simplicity of use
- Very reduced maintenance

The adjustable electric flows are constituted by the external body, by the internal piston group, by the contrast spring, by a calibration element that fixes the point of intervention of the electrical contact. and by a microswitch. By sliding the electrical part on the body, select the corresponding intervention point on the graduated scale. when the piston moving on the basis of the flow will go to correspond to the selected value will switch the electrical contact.
Main features
- Wide selection of measurement scales
- Wide resistance to even high pressures
- Assembly in all directions
- Discrete precision and high simplicityof use
- Very reduced maintenance

Pallet magnetic flow switches are the most used devices in most industrial applications, for on/off control of gas and liquid flow rates. Two oscillating magnets placed on the same axis (the first integrated in the blade and the second integrated with the electric apparatus) repel each other through a flange of non-magnetic material. The flange separates the housing, which contains the electrical equipment, from the blade inserted into the pipe. In the absence of flow, the blade is kept in its rest position by the balancing and repulsion action of the two magnets placed opposite each other, having the same polarity. When the flow pushes the pallet, the integrated magnet starts moving, and the magnetic
field pushes the integrated magnetized switch. Switching of electrical contact
is fast and reliable.
Main features
- Wide selection of pallets that are suitable for large diameter pipess
- Materials available for the normal types of applications (brass, Inox)
- High simplicity of use
- Very reduced maintenance