Sight Glass Fittings: Your Window into Process Vessels

Sight glasses—also referred to as viewports or sight windows—provide essential visibility into the internal conditions of process vessels, tanks, and pipelines. Built around a robust bolted-flange construction, each unit secures a precision-engineered glass disc between premium gaskets, delivering dependable, safe, and clear observation of your process media and operating conditions.

Where They Excel

Sight glass fittings are utilised across a broad range of industrial applications, enabling operators to monitor, verify, and troubleshoot processes in real time. Common installation points include:

• Pressure vessels
• Storage tanks
• Silos
• Stirred and agitated vessels
• Separators
• Pipelines and transfer lines

Beyond Basic Visual Access

John Moncrieff Ltd delivers a complete ecosystem of process-visibility solutions—far beyond conventional sight glass assemblies. Our accessory portfolio ensures clarity, safety, and operational resilience even in demanding environments:

• Wiper systems: Maintain visibility in the presence of condensate, coatings, or particulate buildup.
• Sight glass luminaires: High-efficiency lighting to enhance clarity in low-light processes or enclosed vessels.
• Process cameras: Continuous monitoring, remote viewing, and process documentation.
• Replacement glass & gaskets: Ensure uptime with readily available, compliant spare components.

Your Partner for Process Visibility

When you need greater operational insight, reliable monitoring, and robust equipment performance, John Moncrieff delivers. Our sight glass solutions are engineered for demanding duty conditions across chemical, pharmaceutical, food, beverage, energy, and heavy-industry sectors. Reach out to our technical team to specify the right configuration for your vessel, pipeline, or process environment.