Tempered Circular Sight Glass

What is a Sight Glass?

A Sight Glass is a transparent or translucent device installed in pipelines, tanks, or vessels, designed for visual inspection of fluid levels and flow within a system. It allows operators to observe and monitor liquids or gases, facilitating real-time assessment for efficient operation, maintenance, and safety.

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Ever wondered how a Sight Glass enhances visibility in fluid systems?

The Sight Glass plays a pivotal role in visually monitoring liquids across various industrial and mechanical settings. This transparent device is strategically installed in pipelines, tanks, or containers, allowing operators to directly observe and assess the flow and level of substances within the system. Its design provides a clear window that facilitates the detection of potential issues, optimization of performance, and real-time informed decision-making.

Beyond its practical function, the Sight Glass also contributes to enhancing safety and efficiency by offering a transparent view of internal processes, which is crucial in environments where direct visibility is essential for optimal operation.

What Are The Types Of Circular Sight Glass?

There are three main types of circular sight glass that we sell at Zight. The type you will need depends on factors like budget, application, and manufacturer requirements. Read the manual for your circular sight glass carefully to make sure you choose the correct replacement.

Borosilicate Flat Sight Glass Standard DIN7080

This type is made from tempered borosilicate glass. “Tempered” sight glass refers to the process of thermally treating the material so that it becomes stronger and more resilient. These are important qualities for a circular sight glass.

Tempered Soda Lime Sight Glass

This type is made from tempered soda lime. It’s a less expensive option than a borosilicate sight glass and works just as well, providing it’s not exposed to food, drugs, chemicals, or temperatures above 300 degrees Fahrenheit.

Flat Quartz Sight Glass

Quartz sight glasses can withstand heat up to 1000 degrees F and thermal shock up to 280 degrees F. They’re quite a bit more expensive than tempered borosilicate or tempered lime soda sight glasses, but they hold up well in extreme applications.

How Can I Determine If It’s Time to Replace the Sight Glass?

Identifying when to replace your level gauge sight glass involves recognizing three key indicators.

Firstly, check for any leaks. Over time, water and steam erosion or accidental knocks can compromise the integrity of the glass tube, leading to leakage.

Secondly, assess the clarity of the glass surface. If it appears cloudy or dirty, obstructing your view of water levels, it indicates that the sight glass is no longer effective, necessitating a replacement.

Lastly, be vigilant for signs of thinning glass. This is an early warning sign that the tube may soon crack or leak, making timely replacement essential for maintaining operational integrity.

What Do I Need To Install Circular Sight Glass?

Before you begin the process of installing a circular sight glass, make sure you have these necessary supplies on hand:

  • Wrench
  • Torque wrench
  • Sight glass plate (tempered borosilicate, tempered soda lime, or quartz)
  • Rubber gaskets
  • Protective gloves
  • Protective eyewear
  • Set of gaskets for the sight glass

AI-Guided Sight Glass Mastery: Essential Tips in 3 Videos!

Data Sheet Sight Glass Cover

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  • Manufactured in North America to the highest quality standards.
  • Our glass and parts aren’t shipped from overseas, so you’re not eating the cost to have it shipped across the Atlantic and stored in the US.
  • You get the quality parts you expect with substantial savings.

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Contact Zight

Get in touch with us via email or phone

Zight, a company of United Glass LLC


+1 785 390 0003




Texas Location and Corporate Office:
700 Smith St #61070
Houston, TX 77002