Boiler Water Level Gauge

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The BN200 series is bi-color boiler water level gauge that meets ASME Section I –Power Boiler requirements, using high quality material and adhering to safety standards. The BN200 Bi-Color water level gauge can handle a maximum pressure of 220 kgf/cm2 (216 barG), and a maximum temperature of 701°F (372 °C).

Principles of the BN200 Series Bi-Color water level gauge

The air phase in the water level gauge is red and the liquid phase is green, ensuring a very clear visual of the water level. When the prism shaped liquid chamber of the water level gauge is filled with a clear liquid, due to the prism effect of the liquid chamber section, the light injected is bent extensively. However, when the liquid chamber is filled with air (gas) the light bending effect is slight and almost all of the injected light travels straight.

When color filters (red/green or red/blue) are set in the illuminator, as show in the diagrams on the left, the following different light phenomena occur: red light is transmitted when air (gas) covers the glass surface while green light is transmitted when transparent liquid covers the surface.

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  • Developed for use with the BN200 series water level gauge, we have created a composite unit comprised of a special metal ring fused to glass that is extremely heat resistant. As the glass and metal are integrally fused together, the glass is stronger than most products, reducing the chance of glass damage almost completely.
  • Our innovative glass solution contains several oxides to improve its resistance to alkalis. These include zirconia, rare earths and alumina, all of which are highly resistant to dissolving, and maintain this property when incorporated into glass. It also contains properties found in regular glass such as heat stability and mechanical strength, allowing it to be used for industrial applications.

For more information, download our brochure and data sheet here: