Since the release of the first positive displacement flowmeters to Japan market in 1949, OVAL has been developing and producing wide range of flowmeters, related products and system products.
Applications of these products have been extended to variou processes in the industries and the products earned high reliability from customers. Utilizing accumulated know-how as valuable
- Positive displacement flowmeters.
- Coriolis flowmeters.
- Vortex flowmeters.
- Thermal mass flowmeters.
- Turbine flowmeters.
- Meter provers.
Positive displacement flowmeter
-In principle, positive displacement flowmeter requires no external energy such as electricity. Flowrate is calculated from the number of revolutions of a rotor(s) activated by the energy of fluid. Generally, positive displacement flowmeter offer high accuracy measurement and is suitable for totaling the flowrate.
-Coriolis flowmeter is a mass flowmeter to directly and continuously measure the "mass", the only characteristic of fluid that is not affected by the change in temperature, pressure, viscosity, and density of it. Based on a unique principle utilizing Coriolis force, wide range of mass flowrate based system can be configured by detecting the mass flowrate in high accuracy and sensitivity and converting it to analog or frequency output. In addition to general liquids, flowrate of foods, chemicals, slurry, high-density gas, etc. can be measured. A major feature of the Coriolis flowmeter is a complex sensor that can measure temperature and density simultaneously with flowrate.
-Vortex street occurs alternately and regularly in the right and left under a given condition downstream of an object (delta shape bluff body) placed in the flow. This vortex is called Karman vortex, enabling you to know the flowrate from the frequency caused by. Vortex flowmeter is applicable to liquid, gas, and steam. It has no moving part and features low pressure loss. It is an easy-to-use flowmeter with high durability and repeatability and is widely adopted in various fields including calorie transactions and calorie control.
- The operation of electromagnetic flowmeter is based on Faraday's law of electromagnetic induction, i.e., when a conductive object (conductor) passes through magnetic field, electromotive force is produced at both ends of the conductor and the magnitude of the electromotive force is related to the volume rate of flow. With an electromagnetic flowmeter, conductive fluid can be measured without being affected by the temperature, pressure, density, viscosity, and/or conductivity of fluid, and flowrate of corrosive fluid can be measured with negligible loss of pressure.
-Turbine flowmeter measures the flowrate from the number of revolutions of a blade placed in the flow. The speed of revolutions of the blade with an axis parallel to the flow direction is proportional to the speed of the flow. Utilizing the capability of highly accurate measurement for wide range of viscosity.
Thermal mass flowmeter
-The sensor unit of a thermal mass flowmeter consists of two sheath pipe-shaped sensors acting as flow speed sensor and temperature sensor, respectively. The flow speed sensor is controlled (heated) to a specified temperature difference from ambient temperature. The heat taken away from the flowrate sensor due to the fluid flow is correlated to the mass flow. Therefore, the mass flowrate can be obtained from the amount of power applied to the flowrate sensor to compensate for the removed heat.
Controller flowmeter for energy saving
-For energy saving, it is important for everyone in a company to take appropriate activities.
We think that showing the effect of the activities in digital format and evaluating the effect in digital help expanding energy saving activities. We can offer inexpensive flowmeters for measuring “energy fluids” including air, steam, water, and oil.