Viewports: The Strongest Sight Glass Indicators

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
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
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.

 

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®.
Approvals and Technical Data:
- 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