Sanitary-grade Vision Glasses With Zero Blind Spot Design

A sanitary sight glass enables clear process observation while maintaining hygienic conditions through a zero-dead-leg design. The glass mounts flush with the pipe or vessel inner wall, eliminating crevices and entrapment zones. Borosilicate glass provides high clarity and thermal shock resistance. This combination ensures visibility without compromising cleanability.

How to select a sanitary sight glass?

1. Choose connection: flush-mount for zero dead-leg, ferrule for standard service.

2. Specify surface finish: Ra ≤ 0.4 μm for pharmaceutical, Ra ≤ 0.8 μm for food/dairy.

3. Select glass type: borosilicate for high clarity and thermal shock resistance.

4. Verify P-T rating: -40°C to +200°C, pressure up to 16 bar.

Common Design Pitfalls – Why and How to Avoid

• ⏳ Ferrule connections: Create dead leg. → Specify flush-mount NA-Connect™.

• 🔬 Rough surfaces: Trap residue, fail CIP. → Specify Ra ≤ 0.4 μm electropolished.

• ⚗️ Wrong glass: Tempered glass lacks thermal shock resistance. → Specify borosilicate (ISO 3585).

• 🧪 Ignoring P-T rating: Glass fails under extremes. → Verify -40°C to +200°C, up to 16 bar.

Zero-Dead-Leg Design

Traditional ferrule connections create a dead leg between glass and pipe wall. Zero-dead-leg solutions eliminate this.

Solutions:

• Flush-mount NA-Connect™ design: Eliminates dead leg.

• Metal-fused glass-to-metal seal: Crevice-free, no separate gaskets.

• Concave glass: Optimizes flow and cleanability.

Hygienic sight glass with zero-dead-leg design meets ASME BPE and EHEDG guidelines. Pipe connections follow DIN 11850.

Materials and Specifications

Glass Technology

Borosilicate glass is the industry standard for high clarity, pressure resistance, and thermal shock resistance.

Advantages:

• Mechanically pre-stressed: Strength comparable to steel.

• USP Type I: Meets pharmaceutical standards.

• Temperature: -40°C to +200°C continuous, excursions to 280°C.

• ISO 3585: Defines thermal and mechanical properties.

Metal-fused glass eliminates separate gaskets and torque specifications.

CIP/SIP Compatibility

Requirements:

• Ra ≤ 0.4 μm finish for optimal cleanability.

• Flush-mounted design: No crevices or dead zones.

• 316L construction: Resists corrosion and thermal cycling.

• Temperature rating: Up to 200°C for steam sterilization.

Applications

Pharmaceutical & Biotech: Bioreactors, sterile water, API. 316L, Ra ≤ 0.4 μm electropolished (ASME BPE SF4), NA-Connect™, borosilicate (ISO 3585), SIP to 150°C, up to 16 bar.

Food & Beverage: Dairy, beer, wine, juice. 304/316L, Ra ≤ 0.8 μm, clamp connections, borosilicate with EPDM, CIP to 85°C, atmospheric to 10 bar, 3-A Sanitary.

Aseptic Processing: Cell culture, sterile filling. 316L, Ra ≤ 0.4 μm, NA-Connect™, metal-fused borosilicate (USP Class VI), SIP to 150°C, up to 16 bar.

Design Summary

A sanitary sight glass provides clear visibility without compromising hygiene through flush-mounted design, zero-dead-leg sealing, and electropolished finish (Ra ≤ 0.4 μm per ASME BPE SF4). Borosilicate glass (ISO 3585) offers high clarity and thermal shock resistance.

A 2 sanitary sight glass (2-inch) with clamp connections suits small-bore lines. A 4 sanitary sight glass (4-inch) with flush-mount NA-Connect™ suits larger vessels. Hygienic sight glass designs meet ASME BPE, EHEDG, and 3-A Sanitary guidelines.

Sanitary Stainless Steel Straight Welded Sight Glass

• We can supply Sanitary Welded Sight Glass, Hygienic Clamped Sight Glass, Hygienic Thread Sight Glass, Sanitary Four Way Sight Glass, Sanitary Union Type Sight Glass, Hygienic Sight Glass With Light.
• Glass is made of tempered glass which can bear Max working 10 Bar. Replaceable.
• Screw Blot: Full Stainless Steel.
• EPDM, Silicon, Viton and PTFE seats are available, making the Sight Glass suitable for many applications in such as food, dairy, beverage, meat processing, vacuum processing, pharmaceutical, chemical, and many other industries.
• It is necessary you specify at the time when orders be placing if heat numbers and MT"s are required.

Product Description

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