Borosilicate Sight Glass is a high-performance industrial glass component made from borosilicate 3.3 material, designed for pressure vessels, reactors, boilers, and other high-temperature equipment. With excellent thermal shock resistance, chemical durability, and high transparency, it provides reliable visual inspection solutions.
Borosilicate Sight Glass is a high-performance industrial glass component manufactured from borosilicate 3.3 glass, designed for visual inspection applications in pressure vessels, chemical equipment, boilers, and other high-temperature industrial systems.
With excellent thermal shock resistance, chemical stability, and high transparency, our borosilicate sight glass provides reliable observation solutions under demanding working conditions. We support custom manufacturing based on different diameters, thicknesses, shapes, and customer drawings to meet various industrial requirements.
Excellent Thermal Shock Resistance
Borosilicate Sight Glass features a low thermal expansion coefficient, allowing it to withstand rapid temperature changes and reduce the risk of cracking caused by thermal stress.
High Temperature Performance
Made from borosilicate 3.3 material, the glass provides excellent heat resistance with a continuous working temperature of up to 550℃, making it suitable for high-temperature equipment.
Superior Chemical Resistance
The dense glass structure offers excellent resistance to acids, alkalis, and water, ensuring stable performance in chemical and industrial environments.
High Transparency
With light transmittance up to 92%, the glass allows clear visual observation of internal conditions during equipment operation.
Custom Processing Capability
Available in customized round, square, and special shapes with options for different thicknesses, surface treatments, coating, and tempering processes.
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| Item | Specification |
| Material | Borosilicate Glass 3.3 |
| Density | 2.23 ± 0.02 g/cm³ |
| Hardness | >7 |
| Tensile Strength | 4.8×10⁷ Pa |
| Thermal Expansion Coefficient | (3.3±0.1)×10⁻⁶ K⁻¹ |
| Thermal Conductivity | 1.2 W/(m·K) |
| Light Transmission | 92% |
| Softening Point | 810±10℃ |
| Continuous Working Temperature | ≤550℃ |
| Thermal Shock Resistance | 280℃ |
| Dielectric Strength | 5×10⁷ V/M |
| Thickness Range | Customized, minimum 0.5mm available |
| Surface Quality | 0/0, 40/20, 80/50 |
| Processing Options | Cutting, Polishing, Coating, Tempering |
Borosilicate Sight Glass is widely used in industries requiring reliable visual inspection and high temperature resistance, including:
· Pressure vessels and reactors
· Chemical processing equipment
· Boiler observation windows
· Industrial pipelines
· High-temperature furnaces
· Laboratory equipment
· Food and pharmaceutical processing equipment
· Oil and gas equipment
To meet the requirements of different industrial equipment and inspection systems, our Borosilicate Sight Glass is available in a wide range of shapes, dimensions, and processing options. Whether you require standard products or fully customized components, we can manufacture according to your drawings and technical specifications.
Available Shapes
· Round sight glass
· Square sight glass
· Rectangular sight glass
· Oval sight glass
· Special-shaped sight glass
· Customized glass discs and plates
Processing Capabilities
Our advanced manufacturing equipment supports a variety of precision processing services, including:
· CNC precision cutting
· Precision edge grinding
· Polished edges
· Drilling and countersunk holes
· CNC machining
· Tempering
· Surface coating
· Silk screen printing (optional)
· Custom dimensions and thicknesses
Flexible Customization
We can manufacture according to:
· Customer drawings
· CAD or PDF files
· Sample products
· OEM & ODM requirements
Borosilicate Sight Glass mainly consists of high-quality borosilicate 3.3 glass material, which provides excellent optical performance and thermal stability.
The material structure includes:
· High-purity borosilicate glass substrate
· Optional tempered treatment layer
· Customized surface processing according to application requirements
Borosilicate 3.3 glass is selected for its low expansion coefficient, excellent durability, and stable performance under temperature fluctuations.
To ensure safe delivery, Borosilicate Sight Glass products are carefully packed with protective materials to prevent damage during transportation.
Packaging solutions include:
· Individual protective packaging
· Shock-resistant cartons
· Wooden cases for bulk shipments
· Export-standard packaging solutions
We support international shipping by sea, air, and other transportation methods according to customer requirements.
Selecting the right glass material is essential for ensuring equipment safety, long-term reliability, and stable operation. Compared with ordinary glass, Borosilicate Sight Glass offers superior thermal stability, chemical resistance, and mechanical strength, making it the preferred choice for industrial observation windows and pressure equipment.
| Feature | Borosilicate Sight Glass | Ordinary Glass |
| Heat Resistance | Continuous working temperature up to 550℃ | Limited heat resistance |
| Thermal Shock Resistance | Excellent, suitable for rapid temperature changes | Easily cracks under sudden temperature changes |
| Chemical Resistance | Resistant to acids, alkalis, and most chemicals | Limited chemical resistance |
| Light Transmission | Up to 92% | Good, but decreases over time in harsh environments |
| Mechanical Strength | Higher after tempering | Lower impact resistance |
| Custom Processing | Custom size, thickness, shape, drilling, coating, tempering | Limited processing options |
| Industrial Applications | Pressure vessels, boilers, reactors, pipelines, laboratory equipment | General household and architectural applications |
Q1.How do I choose the right Borosilicate Sight Glass for my equipment?
Selecting the appropriate borosilicate sight glass depends on several factors, including operating temperature, working pressure, installation size, glass thickness, and the type of medium inside the equipment. Our engineering team can recommend suitable specifications based on your application or technical drawings.
Q2. Can Borosilicate Sight Glass be used in high-pressure applications?
Answer
Yes. Borosilicate sight glass is widely used in pressure vessels and industrial equipment. The suitable thickness and installation method should be selected according to the operating pressure and safety requirements. We can recommend appropriate solutions based on your working conditions.
Q3.What edge finishes are available?
We offer various edge finishing options, including flat polished edges, arrised edges, beveled edges, and precision ground edges. Different edge treatments can improve installation safety and meet different sealing requirements.
Q4.How should Borosilicate Sight Glass be stored and handled?
The glass should be stored in a clean and dry environment and handled carefully to avoid edge impacts or scratches. During transportation and installation, protective packaging and appropriate lifting methods are recommended to maintain product quality.
Q5.Can you support OEM or private label projects?
Yes. We provide OEM and ODM manufacturing services for distributors, equipment manufacturers, and industrial projects. Custom logos, labels, packaging, and technical specifications are available upon request.
Q6.How can I request a quotation?
Simply send us your required dimensions, thickness, quantity, application, or technical drawings. Our sales and engineering team will review your requirements and provide a suitable solution together with a competitive quotation.
Looking for a reliable Borosilicate Sight Glass manufacturer for your industrial project?
We provide high-quality borosilicate 3.3 sight glass with flexible customization services to meet different application requirements. Whether you need standard products or fully customized solutions, our engineering and sales teams are ready to support your project from design to delivery.
Our services include:
· Custom sizes, shapes, and thicknesses
· OEM & ODM manufacturing
· Technical drawing support
· Fast quotation and sample service
· Stable production capacity
· Professional export packaging and global delivery
Contact us today to discuss your project and receive a customized quotation from our experienced team.