Redline Borosilicate Tube
Manufactured in borosilicate glass, it is used in numerous applications where both chemical resistance and low thermal expansion coefficient are required.
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.
The red line tube used in level gauge glasses is a specialized feature designed to enhance the visibility of fluid levels in a broad range of industrial applications. This tube incorporates distinct red and white lines that run along its length, providing a stark contrast against the color of the fluid or the background, making it easier to read levels at a glance. Particularly useful in environments with poor lighting or where fluids are clear or have low visibility, the red line aids in precise level determination, reducing reading errors and improving operational safety.
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% |
Red line — High contrast
The red line among two white lines creates an optical effect that magnifies the central line, allowing distant observation of the fluid and increasing the observation distance of the liquid.
Importance of the redline sight glass
The Redline tube goes beyond serving as a visual aid; it is a vital safety feature. The combination of red and white lines produces a high-contrast display, simplifying the task for operators to accurately monitor the water level. This is crucial in high-pressure environments where swift and precise readings are essential to avert hazardous situations.
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