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Elongated Vessel Sight Glass
The Elongated Vessel Sight Glass is a oval viewing window designed for continuous observation of liquid levels, flow conditions, and process activities inside tanks, reactors, and pressure vessels. Its extended viewing area provides enhanced visibility compared to conventional circular sight glasses.
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Technical data
Elongated Vessel Sight Glass for Continuous Process Monitoring
The Elongated Vessel Sight Glass is specifically designed to provide an extended viewing area for monitoring liquid levels, mixing processes, foam formation, sediment accumulation, and product conditions inside industrial vessels and tanks.
Unlike conventional round sight glasses, the elongated design offers a larger observation field, allowing operators to monitor a broader section of the process without multiple viewing ports. This makes it particularly suitable for level indication systems, storage tanks, reactors, separators, and processing vessels.
Manufactured using high-quality borosilicate glass, tempered glass, quartz glass, or customized transparent materials, the sight glass assembly ensures excellent optical clarity, thermal resistance, and mechanical strength.
The frame and mounting assembly are available in stainless steel 304, stainless steel 316L, carbon steel, and other corrosion-resistant materials to meet demanding industrial requirements.
Elongated Vessel Sight Glasses are widely used in chemical processing, pharmaceutical manufacturing, food production, water treatment, petrochemical plants, and energy facilities where continuous visual inspection is critical for process safety and efficiency.
Elongated Vessel Sight Glass— Technical Data
| Item | Details |
|---|---|
| Application | Elongated sightglasses Lumistar of the series LSG / LSGR / LSGRR may be used to observe the interior of reactors, columns, silos, vessels, storage tanks,pipelines or as liquid level indicators.They are delivered ready to be welded into onto a vessel wall, complete with appropriate seals, glass plate and cover bolts.The D-end shape facilitates easier machining of the vessel wall prior to welding in the unit. |
| Operating conditions | Nominal pressure 2,5/6/10/ 25 bar (see table overleaf) Vacuum Note: The nominal pressure indicated refers to the design base of the sightglass. When welded into the vessel concerned, the base frame becomes part of the vessel wall. It is necessary, therefore, that appropriate strength calculations are made on all vessels concerned with respect to the design pressure and size of the vessel and in accordance with the relevant design code. If found to be necessary,reinforcement of the vessel wall has to be carried out. |
| Operating temperatures | 100 °c max. with sodium silicate glass to DIN 8903 243°C max. with borosilicate glass to DIN 7081 Note: The above indicated temperatures refer to the use of unprotected glassplates, with no protective mica sheets. |
| Standard materials | Base flange: Boiler plate RSt 37-2/HII/AISI 316 Ti/AISI316L Cover flange: Boiler plate RSt 37-2/HII /AISI 304 /AISI 316 Ti/AISI316L Glass plates (Transparent): Sodium silicate to DIN 8903; Borosilicate to DIN 7081 Seals: KLINGERsil C4400, EPDM, Silicone, PTFE Cover bolts to DIN 912: Carbon steel,zinked, quality 8.8; Stainless steel A2-70 Other materials on request. |
| Certificates | To be supplied against extra charge to DIN EN 10204. |
| Standard versions (see left) | – Base flange with bolt tappings drilled through, type designation – DB – Base flange with blind tappings, type designation – SL – Base flange with radiused back (to correspond to vessel radius), type designation-R |
| Options | – Version with double glasses (not available for PN 25). – Fluted glass plate for liquid level indication (only available for PN 25). Special dimensions. – Closed back (base flange) version with drilled and tapped holes at the ends for pipe connections so that the unit may be used as an external gauge of a liquid level. |
| Type designation | Series LSG: Base and cover flange in boiler plate RSt 37-2 Series LSGR: Base flange in stainless steel, Cover flange in boiler plate RSt 37-2 Series LSGRR: Base and cover flange in stainless steel |
Elongated Vessel Sight Glass— Drawing
Standard Types Dimensions
| Type LSG LSGR LSGRR | Nominal pressure (PN) | Dimensions | Free view | Screws M10 | Glass plate dimensions | Thickness of the flanges | Weight (kg) | |||
|---|---|---|---|---|---|---|---|---|---|---|
| A | B | Length | Width | Number C | h₁ | h₂ | ||||
| 2,5-1 | 2,5 | 266 | 116 | 200 | 50 | 8 | 70/10×220 | 25 | 15 | 6,3 |
| 2,5-2 | 2,5 | 341 | 116 | 275 | 50 | 10 | 70/10×295 | 25 | 15 | 7,6 |
| 2,5-3 | 2,5 | 416 | 116 | 350 | 50 | 12 | 70/10×370 | 25 | 15 | 9,8 |
| 2,5-4 | 2,5 | 491 | 116 | 425 | 50 | 14 | 70/10×445 | 25 | 15 | 11,0 |
| 2,5-5 | 2,5 | 566 | 116 | 500 | 50 | 16 | 70/10×520 | 25 | 15 | 12,3 |
| 2,5-6 | 2,5 | 641 | 116 | 575 | 50 | 18 | 70/10×595 | 25 | 15 | 14,2 |
| 2,5-8 | 2,5 | 791 | 116 | 725 | 50 | 22 | 70/10×745 | 25 | 15 | 18,0 |
| 6-1 | 6 | 261 | 96 | 195 | 30 | 10 | 50/10×215 | 25 | 15 | 5,6 |
| 6-2 | 6 | 316 | 96 | 250 | 30 | 12 | 50/10×270 | 25 | 15 | 7,0 |
| 6-3 | 6 | 371 | 96 | 305 | 30 | 14 | 50/10×325 | 25 | 15 | 8,0 |
| 6-4 | 6 | 426 | 96 | 360 | 30 | 16 | 50/10×380 | 25 | 15 | 8,9 |
| 6-5 | 6 | 481 | 96 | 415 | 30 | 18 | 50/10×435 | 25 | 15 | 10,0 |
| 6-6 | 6 | 536 | 96 | 470 | 30 | 20 | 50/10×490 | 25 | 15 | 12,0 |
| 6-8 | 6 | 646 | 96 | 580 | 30 | 24 | 50/10×600 | 25 | 15 | 13,7 |
| 10-1 | 10 | 260 | 80 | 198 | 18 | 12 | 35/10×215 | 25 | 15 | 5,0 |
| 10-2 | 10 | 305 | 80 | 243 | 18 | 14 | 35/10×260 | 25 | 15 | 5,8 |
| 10-3 | 10 | 350 | 80 | 288 | 18 | 16 | 35/10×305 | 25 | 15 | 6,5 |
| 10-4 | 10 | 395 | 80 | 333 | 18 | 18 | 35/10×350 | 25 | 15 | 7,5 |
| 10-5 | 10 | 440 | 80 | 378 | 18 | 20 | 35/10×395 | 25 | 15 | 8,0 |
| 10-6 | 10 | 485 | 80 | 423 | 18 | 22 | 35/10×440 | 25 | 15 | 9,5 |
| 10-8 | 10 | 575 | 80 | 513 | 18 | 26 | 35/10×530 | 25 | 15 | 13,0 |
| 25-1 | 25 | 186 | 80 | 121 | 15 | 10 | 34/17×140 | 25 | 20 | 4,0 |
| 25-2 | 25 | 211 | 80 | 146 | 15 | 10 | 34/17×165 | 25 | 20 | 4,5 |
| 25-3 | 25 | 236 | 80 | 171 | 15 | 12 | 34/17×190 | 25 | 20 | 5,0 |
| 25-4 | 25 | 296 | 80 | 231 | 15 | 14 | 34/17×250 | 25 | 20 | 6,0 |
| 25-5 | 25 | 326 | 80 | 261 | 15 | 16 | 34/17×280 | 25 | 20 | 6,8 |
| 25-6 | 25 | 366 | 80 | 301 | 15 | 18 | 34/17×320 | 25 | 20 | 7,5 |
| 25-8 | 25 | 386 | 80 | 321 | 15 | 18 | 34/17×340 | 25 | 20 | 8,0 |
KEY FEATURES
Large Viewing Area
The elongated design provides a significantly larger observation window compared with standard circular sight glasses, improving process visibility.
Continuous Level Monitoring
Ideal for observing liquid levels, interfaces, foam formation, and sediment accumulation throughout the vessel height.
Modular Design
Multiple viewing lengths and customized dimensions are available to fit different vessel configurations.
Excellent Transparency
Clear visibility for process monitoring
Corrosion Resistant Construction
Frames and mounting components are available in SS304, SS316L, Duplex Stainless Steel, and customized alloys.
Custom Design Support
OEM / ODM customization available
Custom Manufacturing Service
We provide tailor-made solutions according to drawings or technical requirements.
- Custom diameter
- Custom thickness
- Special pressure design
- Edge polishing
- Optical finishing
- OEM / ODM support
- Custom packaging
TYPICAL APPLICATIONS
- Pressure Vessels
- Chemical Reactors
- Boilers & Steam Systems
- Pipeline Sight Glass Assemblies
- Pharmaceutical Equipment
- Food & Beverage Processing
- Industrial Observation Ports
FAQ
A: An elongated vessel sight glass is a rectangular observation window that provides an extended viewing area for monitoring processes inside tanks and vessels.
A:The elongated design offers a larger field of view, making it easier to observe liquid levels and process conditions over a greater vertical distance.
A: Yes. Viewing length, width, frame material, gasket material, pressure rating, and glass type can all be customized.
A: Yes. Borosilicate and quartz glass versions can withstand elevated operating temperatures depending on process requirements.
A: Yes. The assembly can be engineered for pressure-rated vessel applications according to customer specifications.
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