Lumiglas Tubular Sight Glass/Flow Indicator

Flanged at both ends DIN 2642 mating sizes PN 10 for fitting into pipelines

Length over flange: DIN 3202 F1

For visual control of state of fluid and flow in pipelines

Sizes from DN10 to DN200, also available with ANSI flanges
Stainless steel 1.4571(316Ti) flanges or other on request
Metal-(1.4301) or Plexi-glass outer shell for extra protection on request

Operating conditions:
Operating pressure: up to 6 bar, depending on wall thickness (higher ratings on request)

Operating temperature: up to 220°C

Materials of components referred to in adjoining exploded view (within data  sheet below):
Item Part Material
1 Connecting flange Stainless steel 1.4571 or other
2 Glass cylinder Borosilicate glass (DURAN)
3 Ring seals Silicon rubber or other
4 Spacer bars Stainless steel 1.4301 or other
5 Securing bolts A 2 or other
(with spring washer)

Special versions:
– with stainless steel or protective Plexiglas outer shell
– ANSI flanges
– customized length

– The flow indicator is bolted, using suitable gaskets, directly between the mating flanges of the pipeline.
– The flow indicator should be fitted so that no stresses (tensile, compression or torsional) are caused on tightening up.

Ordering information:
e. g. Lumiglas tubular sightglass/flow indicator DN 100, material 1.4571, borosilicate glass, 6 bar operating pressure,
length over flanges 350

product photo: Lumiglas Tubular Sight Glass/Flow Indicator


Lumiglas Sight Glass Fitting Oval – Liquid Level Indicator

For welding into or onto vessel wall
Complete with fully gasketed tongue-shaped glass plate and bolting

Materials: stainless, carbon steels and specials
Nominal pressure: PN 2,5 / PN 6 / PN 10 and PN 25

Lumiglas Oblong Oval Sight Glass Fitting is suitable for welding into or onto vessel walls, this sight glass fitting comes complete with an oblong oval glass plate sealed by gaskets inserted on either side of it and bolted firmly in place.

Ideal for viewing the insides of pipes, vessels, containers, reactors, silos, etc., and used primarily as a liquid level indicator for monitoring e. g. filling levels.

Operating conditions:
– Pressure 2.5/6/10/25 bar
– Vacuum
– Prior to using the fitting, the cut-out reinforcement together with the relevant material of the vessel should be checked in accordance with AD-Merkblatt.

Operating temperature:
100°C when using soda-lime glass to DIN 8903 (on request only)
243°C when using borosilicate glass to DIN 7081
These temperatures refer to unprotected glass, i. e. without a protective layer of mica).

Testing and certification can be provided to DIN EN 10204 3.1/3.2
as required by the customer (at extra charge).

Components and alternative materials:
(as per drawing within data sheet below):
Item Component Material options
1. Base frame Stainless steel 1.4404 or other grades
on request (Steel S235JR+N (RST 37-2))
2. Gaskets KLINGERSil C-4400; Neoprene;
PTFE or others
3. Sight glass plate – Soda-lime glass: thermally
prestressed to DIN 8903,
max. operating temperature: 100°C
– Borosilicate glass: thermally
prestressed to DIN 7081,
max. operating temperature: 243°C
4 Cover frame Stainless steel 1.4404 or other grades
on request (Steel S235JR+N (RST 37-2))
5 Fastening bolts Steel 8.8 or stainless steel A4

Externally mounted liquid level indicator:
Lumiglas oblong oval sight glass fittings are also available with a closed base frame for use as an external liquid level indicator. In this case, the indicator is fed via pipes that run through holes in the base frame plate. The base frame is provided with the relevant drilled or tapped holes for this purpose.

product photo: Lumiglas Sight Glass Fitting Oval