Viewports: Sight Glass Indicators
Viewports are a secure choice as an inline sight glass when you need 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.
|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.