Round Sight Glass with Central Hole | Sight Glass Disc with Wiper Hole, Borosilicate Glass
Product Overview
The round sight glass with central hole is also searched by buyers as sight glass disc with wiper hole, circular sight glass with central bore hole, and round sight glass disc with central opening. In practical sourcing language, these terms usually refer to the same type of circular sight glass disc that is designed to work with a wiper system. The central bore hole version is documented as a disc sight glass with central bore hole Ø10.5 mm to fit wipers of the W/WD series.
This product is used where operators need a clear visual check of liquids, flow, or vessel conditions without opening the system. Supplier literature for DIN 7080 circular sight glasses describes this product family as suitable for pressure duties at temperatures up to 280°C, with no lower temperature limit stated in the source data.
Typical Applications
A round sight glass with central hole is commonly used in industrial equipment that requires both visibility and cleaning functionality. The wiper hole makes it suitable for assemblies where a mechanical wiper is used to keep the viewing area clearer during operation or maintenance.
Typical application areas include:
- process tanks and vessels
- chemical handling equipment
- liquid level observation systems
- process line visual inspection
- industrial sight glass fittings with wiper systems
Material and Performance
Toughened borosilicate glass, ground and polished, with optional extras such as coating available on some product lines.
Material Properties
| Property | Value | Reference |
|---|---|---|
| Material | Borosilicate glass 3.3 / toughened borosilicate glass | |
| Density | 2.23 ± 0.02 g/cm³ | |
| Thermal expansion coefficient (0–300°C) | 3.3 ± 0.1 × 10⁻⁶/K | |
| Softening point | 815 ± 10°C | |
| Strain point | 560 ± 10°C | |
| Bending strength | 160 N/mm² | |
| Young’s modulus | 64 GPa | |
| Hardness | 5.5 Mohs | |
| Temperature duty | Up to 280°C | |
| Low-temperature limit | No lower temperature limit stated in source |
Key Advantages
- Central bore hole for wipers: makes it compatible with wiper-equipped sight glass assemblies.
- Heat resistance: suitable for pressure duties up to 280°C in the referenced DIN 7080 literature.
- Chemical resistance: borosilicate glass 3.3 is known for strong resistance to water, acids, alkalis, and organic substances.
- Optical quality: ground and polished surfaces support clear visual inspection.
- Industrial fit: available in standard circular sizes used in DIN 7080-type sight glass fittings.
Technical Specifications
Central Hole Version: Standard Dimensions and Pressure Ratings
| Outer Size (D × s, mm) | Free View (mm) | Nominal Pressure (bar) | Reference |
|---|---|---|---|
| 84 × 10 | 65 | 4 | |
| 99 × 15 | 80 | 6 | |
| 114 × 15 | 100 | 5 | |
| 125 × 15 | 100 | 4.5 | |
| 147 × 15 | 125 | 3 | |
| 150 × 15 | 125 | 3 | |
| 175 × 15 | 150 | 2 | |
| 200 × 15 | 175 | 1.5 | |
| 225 × 15 | 205 | 1.5 | |
| 250 × 19 | 225 | 1.5 |
Product Reference Data
| Parameter | Value | Reference |
|---|---|---|
| Product type | Round sight glass with central hole | |
| Alias | Sight Glass Disc with Wiper Hole | |
| Central bore hole | Ø10.5 mm | |
| Wiper compatibility | W/WD series wipers | |
| Glass material | Borosilicate, toughened | |
| Surface finish | Ground and polished | |
| Temperature duty | Up to 280°C | |
| Standard family | DIN 7080 / DIN 8902-type circular sight glass discs |
Quality Proof and Evidence
Insert your real evidence here:
- Inspection report: dimensional check, edge finish, visual quality
- Customer case: real tank, vessel, or process line application
- Test data: pressure test, thermal cycling test, or chemical resistance report
- Certificate: ISO 9001
FAQ
What is a round sight glass with central hole?
It is a circular sight glass disc with a central bore hole, designed to work with a wiper mechanism in industrial sight glass assemblies.
Is “sight glass disc with wiper hole” a common search term?
Yes. Buyers often use that phrase when looking for the central bore hole version used with wipers. The source literature explicitly describes the disc as having a central bore hole to fit W/WD wipers.
What material is usually used?
For the referenced DIN 7080-type version, the material is toughened borosilicate glass.
What temperature can it handle?
The referenced product literature states pressure duties at temperatures up to 280°C, with no lower temperature limit stated in that source.
CTA
Request a Quote
Download the Detailed Datasheet
Contact Us for Samples
