Double Glass Sight Glass Fitting

The Double Glass Sight Glass Fitting from John Moncrieff Ltd is engineered for applications demanding an extra level of operational security. This robust circular flange assembly is supplied fully pre-built and ready for bolting directly onto an existing weld pad or nozzle flange—eliminating onsite glass handling and ensuring fast, safe installation.

Two sight glass discs are separated by a precision-machined spacer ring and sealed independently. In the event of damage to one disc, the second remains fully functional, maintaining service integrity under the unit’s full rated operating conditions. This dual-barrier design significantly enhances safety and reliability in critical process environments.

Key Features

• Direct Bolt-On Design: Circular flange assembly ready to mount onto weld pads or nozzle flanges.
• Dual-Disc Safety System: Two glass discs with independent seals provide continued operation if one is compromised.
• Spacer Ring Construction: Maintains precise separation and structural integrity between the two glasses.
• Nominal Sizes: DN 50 to DN 200.
• Viewing Diameter: 50 mm to 175 mm.
• Material Options: Stainless steel, carbon steel, and speciality alloys.
• Inter-Glass Heating Available: Optional heated configuration to prevent condensation or product solidification.

Typical Applications

• Chemical and petrochemical processing
• Pharmaceutical and biotech production
• Food and beverage manufacturing
• Energy and utility sectors
• Any process requiring high-reliability visual inspection

For processes where uninterrupted visibility is essential, the Double Glass Sight Glass Fitting delivers enhanced safety, robust construction, and long-term reliability—engineered to meet demanding industrial requirements.

Technical Specifications: