# Industrial Technical Sight Glass Window

> Industrial Technical Sight Glass Window — a sight / viewing glass. Specs, RFQ checklist and custom sizes to drawing.

- Page: https://machiningglass.com/products/industrial-technical-sight-glass-window/
- SKU: MG-DD5287
- Category: Industrial, Architectural & Appliance Glass > Sight Glass & Industrial Viewing Windows
- Image: https://machiningglass.com/wp-content/uploads/2026/10/Industrial-Technical-Sight-Glass-Window.webp
- Updated: 2026-10-24

Model: sight glass 04.

## Overview

The Industrial Technical Sight Glass Window is supplied as a sight / viewing glass. Listed geometry: size Od From 25mm to 200mm, equal shape. Optical / electrical data: transmittance 90% ~ 92%, sheet resistance Long working temperature ≤ 450 ° C, short time working ≤ 500 ° C. Temperature Long working temperature ≤ 450 ° C, short time working ≤ 500 ° C. Dimensions, material grade, coating and finish can be quoted to your drawing; the values above are the listed starting point.

## Specifications

| Parameter | Value |
| --- | --- |
| Shape | Equal |
| Size | Od From 25mm to 200mm |
| Model NO. | sight glass 04 |
| Connection | Welding |
| Item | Technical Sight Glass Windows |
| Process | Cut, Polish, Ground, Tempered |
| Property 1 | Borosilicate Heat Resistant |
| Shipment | by Sea, by Air, by Courier |
| Head Code | Hexagon |
| Tempered soda lime sight glass | Cost-effective for normal & medium-low temperature equipment without strong corrosive media; |
| Borosilicate sight glass | Wide temperature range & superior thermal shock resistance, perfect for high-temperature furnaces & thermal cycling chambers; |
| Stepped optical disc | Micron-precision tier structure with zero optical distortion, dedicated for optical sensors & spectral testing instruments. |
| Optional Material | Tempered soda lime glass / Heat-resistant borosilicate glass / High transmittance stepped optical glass |
| Visible Light Transmittance | 90% ~ 92% |
| Standard Thickness | 2/3/4/5/6/8/10/12/15mm |
| Tempered soda lime | -30ºC ~ 180ºC |
| Borosilicate glass | -40ºC ~ 300ºC |
| Available Styles | Flat sight window / Concentric stepped sight disc / Square embedded sight panel |
| Optional Processing | CNC edge grinding, hole drilling, AR anti-reflection coating, hydrophobic anti-fingerprint coating, silk screen scale printing |
| Safety Feature | Breaks into blunt granular fragments, shatter & splash proof |
| Temperature resistance | Long working temperature ≤ 450 ° C, short time working ≤ 500 ° C |
| Light transmission rate | 95% up |
| Hydraulic Water-resistant strength | More than test 40Kgf/cm ² |
| Thermal stability | T300 ° C |
| Linear expansion coefficient (0-300 ° C) | 3.3 × 10-7 K-1 |
| Softening temperature | 820° C |
| Supplier | Jinan Honhai Glass Company Limited |

## What to specify when you request a quote

- **Glass type and thickness** — listed as “Tempered soda lime glass / Heat-resistant borosilicate glass / High transmittance stepped optical glass”; name the glass and thickness.
- **Temperature and pressure** — listed as “Long working temperature ≤ 450 ° C, short time working ≤ 500 ° C”; give working temperature, thermal shock and any pressure rating.
- **Strengthening and safety** — listed as “Cost-effective for normal & medium-low temperature equipment without strong corrosive media;”; state tempering, lamination or the safety standard.
- **Outline and edges** — listed as “Equal”; send a drawing with outline, holes and edge finish.

## Engineering guides for this part

For material grades and coating options, see [Infrared Window Glass: Material Options for Optical Sensors & Parts](https://machiningglass.com/materials/infrared-window-glass-material-options-for-optical-sensors-parts/). How parts like this are machined and finished is covered in [Precision AR Coating Process for Optical Glass Windows](https://machiningglass.com/capabilities/precision-ar-coating-process-for-optical-glass-windows/). For an application example, read [Quartz Glass Windows for High-Temperature Appliance Modules](https://machiningglass.com/applications/quartz-glass-windows-for-high-temperature-appliance-modules/). Before sending a drawing, check [Thermal Conductivity of Quartz Glass & Fused Quartz: A Process Guide](https://machiningglass.com/resources/thermal-conductivity-of-quartz-glass-fused-quartz-a-process-guide/). A related standard product is [AR Anti-Reflection Optical Window](https://machiningglass.com/products/ar-anti-reflection-optical-window/).

## FAQ

### What sizes and thicknesses are available?

The listing gives size Od From 25mm to 200mm. Custom outlines and thicknesses are made to drawing; state the tolerance you need.

### What optical or electrical performance does it have?

Listed values: transmittance 90% ~ 92%, sheet resistance Long working temperature ≤ 450 ° C, short time working ≤ 500 ° C. Confirm the values at your operating wavelength, angle and temperature when you request a quote.

### What should I include in a quote request?

Include glass type and thickness, temperature and pressure, strengthening and safety and outline and edges, plus quantity and a drawing if the part is custom.

## Request a quote

Send drawings, tolerances and quantity: https://machiningglass.com/contact/?rfq_product_id=4221#mg-rfq

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Source: Custom Precision Glass Machining — https://machiningglass.com/