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Viewports: Inline Sight Glass

Viewports: Inline Sight Glass

Viewports are a great choice as a brewery inline sight glass to view flow

The strongest, most secure sanitary sight glass indicator available, Viewport’s mechanically prestressed windows are available in a sanitary clamp design for sight ports in processing applications or inline visual flow indicators. Unlike some other sight glasses, Viewport sight glasses meet the USP Type 1 standard for pharmaceutical use.

Described as offering the optics of glass and the strength of steel, these glass elements provide a level of safety, and a useful service life, well beyond that provided by conventional tempered glass or plastic used as sight glass indicators. Even at the most extreme temperatures (as high as 536° F) or in overpressure situations, sudden, total failure – that involving leakage or explosive shattering of the glass – essentially never occurs.

Resources Additional Specs
Standard Tube OD d1 Inch/MM d2 Inch/MM d3 Inch/MM S Inch/MM PSIG@ 536 F
1/2″, 3/4″ 0.98″/ 25 mm 0.71″/ 18 mm 0.39″/ 10 mm 0.39″/ 10 mm 230
1″, 1 1/2″ 1.99″/ 51 mm 1.61″/ 41 mm 0.98″/ 25 mm 0.39″/ 10 mm 230
2″ 2.52″/ 64 mm 2.05″/ 52 mm 1.18″/ 30 mm 0.39″/ 10 mm 200
2 1/2″ 3.05″/ 78 mm 2.72″/ 69 mm 1.38″/ 35 mm 0.39″/ 10 mm 200
3″ 3.58″/ 91 mm 2.99″/ 76 mm 1.57″/ 40 mm 0.39″/ 10 mm 150
3 1/2″ 4.17″/ 106 mm 3.54″/ 90 mm 1.97″/ 50 mm 0.39″/ 10 mm 150
4″ 4.69″/ 119 mm 4.02″/ 102 mm 2.17″/ 55 mm 0.47″/ 12 mm 150
6″ 6.57″/ 167 mm 5.98″/ 152 mm 2.95″/ 75 mm 0.63″/ 16 mm 90
8″ 8.56″/ 218 mm 7.80″/ 198 mm 3.94″/ 100 mm 0.71″/ 18 mm 90
10″ 10.55″/ 268 mm 9.65″/ 245 mm 4.72″/ 120 mm 0.79″/ 20 mm 90
12″ 12.56″/ 319 mm 11.81″/ 300 mm 5.51″/ 140 mm 0.87″/ 22 mm 80
*Temperature and pressure apply to sight glass only.

Viewport windows are formed by melting borosilicate glass into a precisely formed metal ring. As the glass cools, it solidifies, preventing the metal ring from contracting back to its theoretical size. The result is a uniform, mechanically prestressed fusion of glass and metal that combines excellent optical characteristics with greatly enhanced physical characteristics. A standout of sight glass indicators, the Viewport discs have an uninterrupted surface with no crevice to trap bacteria, epoxies, resins, or glue – a true fusion. The standard surface finish is 10 Ra μ-in (0.25 Ra μm).

Electropolishing available upon request.

Additional Specs

Viewports are manufactured to fit sanitary clamp connections. With simple and fast installation with no risk of breakage, this sleek, compact, one-piece design provides a cleaner look, less bacteria traps and unsurpassed safety. The Viewport sight glass can be used as a sight glass indicator mounted on a ferrule, a “cross” for inline visual flow indication or as a light port. Many other connection types are also available, as shown on the reverse side. Materials available include 2205 Duplex Stainless Steel, Hastelloy®, Monel® and Inconel®.
  • USP Class VI (tested to confirm biocompatibility)
  • BPE Compliant and TÜV Approved
  • Sight glass fused to metal conforming to DIN7079
  • Borosilicate glass to USP Type I and DIN7080
  • Standard surface finish of 10 Ra μ-in (0.25μm)
  • Material to ASTM/ASME, TÜV and DIN/EN standards
  • Certificate of Conformity to EN 10204-3.1B or 3.1A
  • Pressure Equipment Directive 97/23/EG