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Variable Area Meter

The Variable Area Flowmeter is one of the oldest and mature principles in flow measurement. Right from the outset, the Rotameter convinced with its simple design: a float rises inside a conically shaped glass tube as the flow increases and its position on a scale can be read off as the flow rate. Felix Meyer, the founder of „Deutsche Rotawerke“, was quick to recognise the importance of the variable area flowmeter developed by Karl Küppers who found the perfect shape of a float that causes it to rotate and therefore provides self-stabilization.

The “Rotamesser” – later the “Rotameter” - was the first variable area flow meter with a rotating float and got its name from our company and is today a synonym for the Variable Area Flowmeter. With the arrival of Yokogawa in 1991 initially as cooperation partner, and in 1995 as the proprietors, the company targeted the flow market under the name "Rota Yokogawa".
Yokogawa has set the standard for the variable area flow meter industry since the introduction of the Original Rotameter.

Yokogawa is the first and only supplier to become complete to provide safety excellence for glass and metal Rotameters according to the IEC 61508 and Machinery Directive ISO 13849.

  • Model RAGN Rotameter
    The Rotameter RAGN is the world´s first Glass Rotameter suitable for SIL applications and is designed for continuous flow measurement of liquids and gases.

  • Model RAGK/RAGL Rotameter
    The Rotameters RAGK/ RAGL are specifically designed for the measurement of low flows of liquid and gases. Their main application field is in purging, analyzer and gas sampling systems, laboratories and machinery equipment.

  • Yokogawa´s Customer Standards
    The Rotameter is known all over the world as a reliable measurement instrument and nowadays is synonymous with the variable area flowmeter principle. Yokogawa built this reputation on customer oriented solutions and has the ability to design and manufacture customer specific solutions made of glass or plastic.

  • Yokogawa Rotameter Catalogue
    Yokogawa has selected the most common types of glass & plastic Rotameters and made the ordering as simple as possible with short models and standard flow ranges.

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