What is round soda-lime glass according to DIN 8902 used for?

This glass is used for applications with low thermal and chemical stress under pressure to allow for visual inspection in containers. It withstands temperatures up to 150 °C, with the pressure depending on the diameter and thickness. Soda-lime glass has a moderate resistance to water, acids, and alkalis, and the permissible material defects are standardized according to DIN 8902.

Specifications of Soda-lime glass

Product Specification: Circular sight glass plates

Material: Soda-lime glass

Removal rates and further information about the glass can be found in our info datasheet

Soda-lime sight glasses are required wherever visual inspection of processes in containers must be ensured under pressure, with low thermal and chemical stress.

Operating conditions:


Temperature: 
150 °C permanent

Pressure: depending on diameter and thickness

Calculation of pressure resistance: TOOL - Glass advisor Soda-lime glass

Technical Information:


Coefficient of expansion at 20 °C/300 °C:
 9.5 x 10⁻⁶ K⁻¹

Temperature cycling resistance: 150 °C


Chemical Resistance:


Water resistance DIN ISO 719/720:
 Hydrolysis class 4

Acid resistance DIN 12116: Acid class 1

Alkali resistance DIN 52332: </strong;Alkali class 2

Permissible material defects:


Round bubbles trapped in the glass may have a maximum diameter of 2 mm. Oval bubbles must not exceed the value (length + width)/2 = 2 mm. Tapered bubbles are not permissible.


Permissible bubble frequency

Bubble diameter d3 | Permissible bubble frequency
d3 < 0.3 3 pieces per cm² of viewing area
0.3 ≤ d3 ≤ 0.5 10 pieces per sight glass plate
0.5 < d3 ≤ 1 4 pieces per sight glass plate
1 < d3 ≤ 2 2 pieces per sight glass plate


Dimensional tolerances:


The dimensional tolerances are based on DIN 8902 for sight glass plates made of Soda-lime glass.


Dimensional tolerances according to DIN 8902

Diameter | Tolerance
up to 125 mm ± 0.5 mm
125 to 200 mm ± 0.8 mm
over 200 mm ± 1.0 mm
Thickness
10 to 20 mm ± 0.50 mm
over 20 mm ± 0.80 mm


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Portrait von Dirk Göttgens

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