Sight Flow Indicators - Protective Fence | Noris

Protective Mesh Guard Noris for Sight Flow Indicators

The Noris protective mesh guard provides mechanical protection for glass plates in sight flow indicators and circular tank sight glasses. It is not a standalone indicator or measuring device; rather, it is installed externally to limit glass damage from impact, tools, metallic objects, or operational activities near the line.

Compatibility

• For sight flow indicators with flanged connections
• Available for Noris Bauform 880 to Bauform 887
• Applicable to circular sight glasses per DIN 28120, Noris Bauform 120
• Custom fabrication possible for alternative mesh geometries
• Materials: stainless steel or carbon steel

Role in Installation

The mesh guard reduces the risk of direct mechanical stress on the glass without affecting the pressure rating, temperature class, or chemical compatibility of the sight glass assembly. These parameters are determined by the sight glass, gaskets, glass material, and flange connections.

Typical Applications

• Liquid or gas lines requiring visual flow verification
• Locations adjacent to maintenance walkways or operator zones
• Installations with risk of external impact from tools or portable equipment
• Sight glasses on pump stations, filters, heat exchangers, skid units, and process lines
• Tanks with circular sight glasses requiring external glass protection

Selection Criteria

Selection should be based on sight glass type, DN, bolt spacing, required viewing area, process media, and likelihood of external impact. Stainless steel is recommended for corrosive or outdoor environments.

FAQ

Does it affect visibility?
Slightly reduces the free viewing area but prevents direct contact with the glass.

Does it increase the pressure rating?
No. It is an external mechanical guard only.

Is maintenance required?
Inspect for deformation, corrosion, loose bolts, and any contact between mesh and glass.