Tempered Borosilicate Flow Sight Glasses
Made of Borosilicate 3.3 glass for use as control sight glasses in lubrication equipment, as well as observation ports in reel-type flow sight glasses for piping.
OUR WARRANTY
100% Satisfaction Guarantee
Douglass warrants merchandise against defective workmanship and materials that become apparent within a period of 12 months from the date of receipt of invoice by the purchaser (hereinafter referred to as the warranty period). All liabilities under the warranty provisions shall expire when the warranty period has expired. Please feel free to contact us if you have any questions or comments.
SHIPPING AND PACKAGING
At Douglass, we use a unique and patented packaging method that minimizes the risk of glass damage during shipping. This system ensures your products arrive in perfect condition, just as we would like to receive them ourselves.
We understand that not all glass is the same, so we tailor our packaging techniques based on the type and quantity of products you order. This ensures maximum protection for every shipment.
Tempered borosilicate cylinders, utilized in 360° view sight flow indicators, combine high chemical and thermal resistance with the strength needed for demanding industrial applications. Borosilicate glass, known for its low coefficient of thermal expansion, allows these cylinders to withstand temperature variations and aggressive chemicals without compromising integrity. The tempering process further enhances their durability, making them ideal for observing fluid dynamics in real time from any angle, a crucial feature for processes involving hazardous or high-temperature fluids. These indicators are indispensable in chemical processing, pharmaceuticals, and petrochemical industries, where continuous monitoring of fluid flow, color, and clarity is essential. The 360° visibility offered by these cylinders ensures comprehensive monitoring, facilitating improved process control and safety.
Borosilicate glass tempered — Technical information
Physical properties
| Property | Testing method | Obtained value |
|---|---|---|
| Thermic dilatation coefficient | ISO 7991 | 3.3 × 10⁻⁶ |
| Density at 25°C | SN 7005 13 | 2.23 g/cm³ |
| Refractive index (λ = 587.6 nm) nd | — | 1.472 |
| Maximum annealing temperature | ISO 7884-8 | 1040 ºF |
| Short-term maximum temperature | ISO 7884-7 | 932 ºF |
| Thermal shock resistance | ISO 7884-4 | 5.67 ºF |
| Young's modulus | — | 63 150 MPa |
| Poisson constant | — | 0.2 |
| Thermal conductivity 20°C – 100°C λ | — | (1.2) (w·m⁻¹)(K⁻¹) |
| Photoelastic constant | DIN 52314 | (4.00 × 10⁻⁶) (mm²/N) |
| Specific electrical resistance 10⁸ Ωcm | DIN 52326 | 482 ºF |
| Dimensional tolerance diameter | DIN 7080 | PASS |
Optical / chemical properties
| Property | Testing method | Obtained value |
|---|---|---|
| Hydrolytic resistance | ISO 719 | HGB 1 |
| Acid resistance | ISO 1776 | CLASS S1 |
| Alkaline resistance | ISO 695 | CLASS 2 |
| Chemical composition SiO₂ | — | Minimum content 80% |
| Chemical composition B₂O₃ | — | Minimum content 13% |
| Chemical composition Na₂O + K₂O | — | Minimum content 4.5% |
We invite you to visit /contact for more information about our wide range of products. Whether you require specific details or personalized assistance, our team is here to help. We are committed to providing you with the highest quality solutions and expert guidance tailored to your needs. See the Douglass catalog for detailed specifications and product offerings.