Sight Glass

A reliable source for Glass Fabrication information and leading Glass Fabrication Companies.

It can be installed as the windows of a piping system, an external vacuum tube, or as a component with a frame screwed between two metal pipes. Read More…

Sight Glass Sight glass is used in industrial plants and machines in order to visually observe and monitor liquid and material levels, colors, flows or direction.

Leading Manufacturers

New Haven, IN  |  260-749-9614

We make it our goal to offer the top glass cutting services in the industry. Although we started small when we were founded in 1950, we have grown every year and are now one of the largest glass suppliers in the industry. We make products for more than just the optical industry, and can make customized products to suit any need. Contact us for a quote today!

Request A Quote

S & S Optical Company, Inc. $$$

Cambridge, ON  |  800-315-0387

Glass cutting is a varied industry, and we have done it all for the past 50 years. We believe in manufacturing high quality glass products that will exceed customer expectations every time. Our goal and mission has always been to ensure our customers are satisfied and will come to us with all of their glass needs. Contact us to learn more today!

Request A Quote

Pegasus Glass $$$

Painesville Township, OH  |  440-639-6399

Founded in 1990, Technical Glass Products is a fabricator of Fused Quartz Glassware. We maintain a broad inventory of labware, flat stock, rod and tubes in addition to providing custom fabrication using state of the art equipment to suit your needs. Our commitment to excellence has resulted in TGP becoming America’s fastest growing supplier of stock shapes and fabricated products in the industry.

Request A Quote

Technical Glass Products, Inc. $$$

Chicago, IL  |  773-525-0435

As glass fabricators, Torstenson Glass specializes in flat glass, wire glass, obscure glass, transparent glass, textured glass, heat resistant glass and the FireLite® family of products. We have operated continuously for over 110 years, and we welcome the opportunity to discuss your glass fabricating needs. If we don’t have it, we can generally draw from experience to find you whatever you need.

Request A Quote

Torstenson Glass Company $$$

Vineland, NJ  |  800-982-4734

Glass, Quartz & Vycor® Components fabricated to your specifications. Processing specialties such as Concentric Grinding, Corning Chemical 7931 Grades®, Glass–Quartz Forming, Glass-to-Metal, Glass-to-Glass, Lathe & Hand Tooling, Precision Bore Glass & Quartz Tubing, Quartz-to-Borosilicate Graded Seals, Special End Finishing. ISO 9001:2000 Registration.

Request A Quote

Precision Electronic Glass, Inc. $$$

Elmira, NY  |  800-537-9438

We are a world leader, specializing in glass fabricating and glass parts for over 50 years. Offered are a variety of glass products and services, which include glass cutting, flat glass, wire glass, optical glass, safety glass, colored glass, textured glass, tempered glass and transparent glass.

Request A Quote

Swift Glass Company, Inc. $$$
placeholder image S & S Optical Company, Inc. Pegasus Glass Technical Glass Products, Inc. Torstenson Glass Company Precision Electronic Glass, Inc. Swift Glass Company, Inc.

Tanks, boilers, reactors or vessels may contain components of sight glass in the form of liquid level gauges or inline sight points. Further uses include media vessels in chemical plants and in other industrial settings such as breweries, bio gas plants, pharmaceutical, food processing and beverage.

Also referred to as sight windows or sight ports, sight glass components are important for a number of reasons. For consumer and beverage industries it is necessary to ensure levels remain high. In some machines, without a specific amount of necessary liquids, the engines could seize and cause great damage; therefore it is imperative the levels are monitored to remain in a safe phase.

Sight glass can come in different forms; however the most common type of sight glass is composed of a tempered glass disc between two metal frames which have been secured together allowing the operator of the equipment to determine the level of liquid contained within.

The glass used must be transparent in order for the level of liquid to be observed and therefore color additives or coatings are not typically used with sight glass. However, to ease the reading of the level, a backboard may be a component of the sight glass mechanism.

Sight glass is typically manufactured as safety glass in order to prevent any pressure or tension resulting in breakage and potential physical damage to personnel working with the machinery. However, glass which has been tempered or mechanically stressed prior to installation is less likely to break and therefore it is used for sight glass to reduce the risk of explosions. The glass used for sight glass fabrication is made using soda lime or borosilicate glass.

Soda lime glass tends to be more cost-effective and is a good quality material. However, when tensile strength and a lower coefficient of expansion are required in a piece of sight glass, more expensive borosilicate glass is used. It is unlikely that borosilicate glass will crack or break even when exposed to temperature changes and pressure. Sight glass can be further strengthened through the process of annealing and ion exchange chemical strengthening.

Sight Glass Informational Video