NPTF Sight Glass

NPT Sight GlassNPTF sight glasses and sight windows are for machine vision or live observation of a process in a variety of industries. The glass is fused to a metal housing creating a hermetically sealed single piece part. The connections are NPTF (Dryseal) threads. Most popular sight glass for laser sensors, cameras and quick visual inspection inside a vessel.

Sodalime Glass Fused to a 2205 Duplex Stainless Steel Housing, Partial Glass

The sodalime glass is fused to the metal. The glass does not extend the full length of the housing, where the internal glass surface is slightly concave.

 

Sodalime Glass Fused to a 2205 Duplex Stainless Steel Housing, Full Glass

These sight windows comply with Pressure Equipment Directive, (PED) standard for high pressure testing. The materials comply with VdTUV specifications and DIN/EU designated standards. Reliable sights for general use in commercial and high tech applications such as hydraulics, refrigeration, water heaters, deep sea and oil well cameras and lighting and explosion / combustion viewing. These NPTF sight glasses have a long working life without maintenance. The sightglasses transmit a broad range of wavelengths operating in a high pressure and high temperature environment. Connections are male NPTF, (Dryseal), 8 full threads.

 

Borosilicate Glass Fused to a 2205 Duplex Stainless Steel Housing

Borosilicate has a higher tolerance to thermal shock than sodalime glass. A workhorse of sight glasses, these sights are suitable for a wide range of applications. Ideal configuration for use in low visibility imaging systems operating under high pressure or in sterile applications. Note: borosilicate glass partially fills the height of the metal housing, as such the internal surface of the glass is slightly concave, which distorts the image somewhat. Choose sodalime sight glasses where the glass extends the entire height of the housing, resulting in perfectly flat both sides of the glass.

 

Borosilicate Glass Fused to a Hastelloy C22 Housing

Sight glasses for the most demanding applications. Borosilicate glass fused to a Hastelloy metal housing allows for operating temperatures from -60 °C up to +300 °C with wide temperature swings. Excellent resistance to localized corrosion and stress corrosion cracking. Good resistance to oxidizing corrosives. Ideal configuration for most sophisticated pharmaceutical reaction vessels.

 

NPTF threaded sights for fuel applications, where closer fit is required between threads. Often called "Dryseal", NPTF fittings can seal without a tape or a sealant for low pressure applications with viscous fluid.

nptf sight glass

Sodalime Glass Fused to a 2205 Duplex Steel Housing. Glass thickness is less than the full height of the part. Ideal for viewing the colors or transmitting light, not for pure optical clarity.

Note: The image of the objects behind the glass may be distorted as the glass is slightly concave. For perfect optical clarity choose sight glasses with glass filling the entire height of the housing, where both sides of the glass are flat.

 


Thread Size, NPTF Hex, mm Aperture, mm D, mm H, mm L, mm Max Operating Pressure, bar Min Operating Temperature, C Max Operating Temperature, C Transmitted Wavelength, nm Encole Part Number Price
1/4" 21.0 9.0 9.0 17.0 11.0 100 -30.0 150.0 350 to 2,600 407S05 $209.94 each
3/8" 20.0 10.0 11.0 20.0 13.0 100 -30.0 150.0 350 to 2,600 407S06 $219.85 each
1/2" 27.0 14.0 15.0 25.0 15.0 100 -30.0 150.0 350 to 2,600 407S07 $234.90 each
3/4" 36.0 18.0 19.0 26.0 16.0 100 -30.0 150.0 350 to 2,600 407S09 $248.85 each
1" 41.0 22.0 23.0 30.0 19.0 100 -30.0 150.0 350 to 2,600 407S11 $263.90 each
1-1/4" 50.0 25.0 30.0 30.0 20.0 100 -30.0 150.0 350 to 2,600 407S12 $284.80 each
1-1/2" 55.0 30.0 36.0 32.0 20.0 100 -30.0 150.0 350 to 2,600 407S13 $297.95 each
2" 70.0 37.0 44.0 34.0 22.0 100 -30.0 150.0 350 to 2,600 407S14 $306.80 each
3" 100.0 55.0 70.0 45.0 31.0 100 -30.0 150.0 350 to 2,600 407S16 $384.50 each

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NPTF sight glasses for fuel applications, where closer fit is required between threads. Often called "Dryseal", NPTF fittings can seal without a tape or sealant for low pressure applications with viscous fluids.

nptf sight glass with perfect optical clarity

Glass extends the full height of the part. The sides of the glass are flush with the top and the bottom of the metal housing. Ideal for imaging systems, as the image is not distorted. Both sides of the glass are flat, with the surface approximately 60-20 S-D (scratch - dig).

 


Thread Size, NPTF Hex, mm Aperture, mm H, mm L, mm Max Operating Pressure, bar Min Operating Temperature, C Max Operating Temperature, C Transmitted Wavelength, nm Encole Part Number Price
1/4" 21.0 5.0 15.0 10.0 100 -30.0 150.0 350 to 2,600 413S05 $214.80 each
3/8" 24.0 7.0 15.0 10.0 100 -30.0 150.0 350 to 2,600 413S06 $231.09 each
1/2" 27.0 11.0 25.0 15.0 100 -30.0 150.0 350 to 2,600 413S07 $249.15 each
3/4" 36.0 17.0 26.0 16.0 100 -30.0 150.0 350 to 2,600 413S09 $264.70 each
1" 41.0 19.0 28.0 18.0 100 -30.0 150.0 350 to 2,600 413S11 $298.87 each
1-1/4" 50.0 22.0 30.0 20.0 100 -30.0 150.0 350 to 2,600 413S12 $303.54 each
1-1/2" 55.0 25.0 32.0 22.0 100 -30.0 150.0 350 to 2,600 413S13 $345.94 each
2" 70.0 35.0 35.0 25.0 100 -30.0 150.0 350 to 2,600 413S14 $387.90 each

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Yet for higher corrosion resistant applications than sight glasses with sodalime glass. Ideal sight glass configuration for high pressure tanks, liquid level viewports, deep or shallow seawater; all types or refrigerants, including CO2-based R744; 3-A Standard rated for sanitary applications in pharmaceutical and food processing; IR applications, DUV, lithography, semiconductors, CO2 laser systems.

nptf sight glass

Borosilicate fused to 2205 Duplex Steel. Glass thickness is less than the full height of the part. Ideal for viewing the colors or transmitting light, not for pure optical clarity.

Note: The image of the objects behind the glass may be distorted as the glass is slightly concave. For perfect optical clarity choose sight glasses with glass filling the entire height of the housing, where both sides of the glass are flat.

 

Thread Size, NPT Hex, mm Aperture, mm D, mm H, mm L, mm Max Operating Pressure, bar Min Operating Temperature, C Max Operating Temperature, C Transmitted Wavelength, nm Encole Part Number Price
1/4" 21.0 9.0 9.0 17.0 11.0 100 -30.0 280.0 310 to 2,200 408S05 $141.79 each
3/8" 24.0 10.0 11.0 20.0 13.0 100 30.0 280.0 310 to 2,200 408S06 $150.63 each
1/2" 27.0 14.0 15.0 24.0 15.0 100 -30.0 280.0 310 to 2,200 408S07 $155.00 each
3/4" 36.0 18.0 19.0 26.0 16.0 100 -30.0 280.0 310 to 2,200 408S09 $165.35 each
1" 41.0 22.0 23.0 30.0 19.0 100 -30.0 280.0 310 to 2,200 408S11 $177.09 each
1-1/4" 50.0 25.0 30.0 30.0 20.0 100 -30.0 280.0 310 to 2,200 408S12 $213.94 each
1-1/2" 55.0 30.0 36.0 32.0 20.0 100 -30.0 280.0 310 to 2,200 408S13 $236.47 each
2" 70.0 37.0 44.0 34.0 22.0 100 -30.0 280.0 310 to 2,200 408S14 $270.23 each
3" 100.0 55.0 70.0 45.0 31.0 100 -30.0 280.0 310 to 2,200 408S16 $376.97 each

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For most demanding applications. These sight glasses are ideal for imaging systems experiencing high temperature swings. Sight glasses with NPTF (Dryseal) threads. 

nptf sight glass

Borosilicate fused to Hastelloy C-22. Glass thickness is less than the full height of the part. Ideal for viewing the colors or transmitting light, not for pure optical clarity.

Note: The image of the objects behind the glass may be distorted as the glass is slightly concave. For perfect optical clarity choose sight glasses with glass filling the entire height of the housing, where both sides of the glass are flat.

 


Thread Size, NPTF Hex, mm Aperture, mm D, mm H, mm L, mm Max Operating Pressure, bar Min Operating Temperature, C Max Operating Temperature, C Transmitted Wavelength, nm Encole Part Number Price
1/4" 21.0 9.0 9.0 17.0 11.0 100 -60.0 300.0 310 to 2,200 409S05 $447.72 each
3/8" 24.0 10.0 11.0 20.0 13.0 100 -60.0 300.0 310 to 2,200 409S06 $465.13 each
1/2" 27.0 14.0 15.0 25.0 15.0 100 -60.0 300.0 310 to 2,200 409S07 $478.68 each
3/4" 36.0 18.0 19.0 26.0 16.0 100 -60.0 300.0 310 to 2,200 409S09 $496.08 each
1" 41.0 22.0 23.0 30.0 19.0 100 -60.0 300.0 310 to 2,200 409S11 $529.43 each
1-1/4" 50.0 25.0 30.0 30.0 20.0 100 -60.0 300.0 310 to 2,200 409S12 $585.38 each
1-1/2" 55.0 30.0 36.0 32.0 20.0 100 -60.0 300.0 310 to 2,200 409S13 $647.68 each
2" 70.0 37.0 44.0 34.0 22.0 100 -60.0 300.0 310 to 2,200 409S14 $738.95 each
3" 100.0 55.0 70.0 45.0 31.0 100 -60.0 300.0 310 to 2,200 409S16 $769.82 each

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