NPT Sight Glass

NPT sight glasses are typical NPT fittings having NPT male threads, where the window is encased into the metal housing forming a single-piece part.

Designed up to 7000 psi pressure, these sight glasses have optical clarity suitable for imaging systems and also for looking at oil levels inside pressure vessels, or checking the color of a refrigerant. These NPT sight glasses transmit a broad spectrum of wavelengths, ranging from near-infrared, visible light, to ultraviolet.

Sight glasses with quartz use GE-124 quartz. It's a pure form of silica commonly used in semiconductor equipment. This quartz has high purity for use in a process in semiconductor reactors.

Image Encole Part Number Price Max Operating Temperature Housing Material Thread Window Material Nominal Pipe Size
265A1000 $244.95 each 140 C AISI 316 NPT 3/8" Quartz -
265A1001 $255.78 each 140 C AISI 316 NPT 1/2" Quartz -
265A1002 $259.80 each 140 C AISI 316 NPT 3/4" Quartz -
265A1003 $275.99 each 140 C AISI 316 NPT 1" Quartz -
265A1004 $368.87 each 140 C AISI 316 NPT 1-1/4" Quartz -
265A1005 $409.00 each 140 C AISI 316 NPT 1-1/2" Quartz -
265A1006 $498.16 each 140 C AISI 316 NPT 2" Quartz -
324A1000 $308.36 each 140 C AISI 316 NPT 3/8" Quartz -
324A1001 $326.04 each 140 C AISI 316 NPT 1/2" Quartz -
324A1002 $341.93 each 140 C AISI 316 NPT 3/4" Quartz -
324A1003 $354.68 each 140 C AISI 316 NPT 1" Quartz -
324A1004 $479.00 each 140 C AISI 316 NPT 1-1/4" Quartz -
324A1005 $597.58 each 140 C AISI 316 NPT 1-1/2" Quartz -
324A1006 $662.42 each 140 C AISI 316 NPT 2" Quartz -
405S05 $181.27 each 280 C 2205 Duplex NPT 1/4" Borosilicate -
405S06 $189.55 each 280 C 2205 Duplex NPT 3/8" Borosilicate -
405S07 $198.32 each 280 C 2205 Duplex NPT 1/2" Borosilicate -
405S09 $209.24 each 280 C 2205 Duplex NPT 3/4" Borosilicate -
405S11 $218.53 each 280 C 2205 Duplex NPT 1" Borosilicate -
405S12 $288.89 each 280 C 2205 Duplex NPT 1-1/4" Borosilicate -
405S13 $291.08 each 280 C 2205 Duplex NPT 1-1/2" Borosilicate -
405S14 $386.59 each 280 C 2205 Duplex NPT 2" Borosilicate -
405S16 $496.94 each 280 C 2205 Duplex NPT 3" Borosilicate -
406S05 $287.54 each 300 C Hastelloy C-22 NPT 1/4" Borosilicate -
406S06 $333.95 each 300 C Hastelloy C-22 NPT 3/8" Borosilicate -
406S07 $378.50 each 300 C Hastelloy C-22 NPT 1/2" Borosilicate -
406S09 $435.90 each 300 C Hastelloy C-22 NPT 3/4" Borosilicate -
406S11 $540.00 each 300 C Hastelloy C-22 NPT 1" Borosilicate -
406S12 $622.00 each 300 C Hastelloy C-22 NPT 1-1/4" Borosilicate -
406S13 $712.00 each 300 C Hastelloy C-22 NPT 1-1/2" Borosilicate -
406S14 $1,370.00 each 300 C Hastelloy C-22 NPT 2" Borosilicate -
406S16 $2,321.00 each 300 C Hastelloy C-22 NPT 3" Borosilicate -
407S05 $209.94 each 150 C 2205 Duplex NPTF 1/4" Soda lime -
407S06 $219.85 each 150 C 2205 Duplex NPTF 3/8" Soda lime -
407S07 $234.90 each 150 C 2205 Duplex NPTF 1/2" Soda lime -
407S09 $248.85 each 150 C 2205 Duplex NPTF 3/4" Soda lime -
407S11 $263.90 each 150 C 2205 Duplex NPTF 1" Soda lime -
407S12 $284.80 each 150 C 2205 Duplex NPTF 1-1/4" Soda lime -
407S13 $297.95 each 150 C 2205 Duplex NPTF 1-1/2" Soda lime -
407S14 $306.80 each 150 C 2205 Duplex NPTF 2" Soda lime -
407S16 $384.50 each 150 C 2205 Duplex NPTF 3" Soda lime -
408S05 $141.79 each 280 C 2205 Duplex NPTF 1/4" Borosilicate -
408S06 $150.63 each 280 C 2205 Duplex NPTF 3/8" Borosilicate -
408S07 $155.00 each 150 C 2205 Duplex NPTF 1/2" Borosilicate -
408S09 $165.35 each 150 C 2205 Duplex NPTF 3/4" Borosilicate -
408S11 $177.09 each 150 C 2205 Duplex NPTF 1" Borosilicate -
408S12 $213.94 each 150 C 2205 Duplex NPTF 1-1/4" Borosilicate -
408S13 $236.47 each 150 C 2205 Duplex NPTF 1-1/2" Borosilicate -
408S14 $270.23 each 150 C 2205 Duplex NPTF 2" Borosilicate -
408S16 $376.97 each 150 C 2205 Duplex NPTF 3" Soda lime -
409S05 $447.72 each 300 C Hastelloy C-22 NPTF 1/4" Borosilicate -
409S06 $465.13 each 150 C Hastelloy C-22 NPTF 3/8" Borosilicate -
409S07 $478.68 each 300 C Hastelloy C-22 NPTF 1/2" Borosilicate -
409S09 $496.08 each 300 C Hastelloy C-22 NPTF 3/4" Borosilicate -
409S11 $529.43 each 150 C Hastelloy C-22 NPTF 1" Borosilicate -
409S12 $585.38 each 300 C Hastelloy C-22 NPTF 1-1/4" Borosilicate -
409S13 $647.68 each 300 C Hastelloy C-22 NPTF 1-1/2" Borosilicate -
409S14 $738.95 each 300 C Hastelloy C-22 NPTF 2" Borosilicate -
409S16 $769.82 each 300 C Hastelloy C-22 NPTF 3" Borosilicate -
410S05 $214.08 each 150 C 2205 Duplex NPT 1/4" Soda lime -
410S06 $231.05 each 150 C 2205 Duplex NPT 3/8" Soda lime -
410S07 $248.12 each 150 C 2205 Duplex NPT 1/2" Soda lime -
410S09 $262.12 each 150 C 2205 Duplex NPT 3/4" Soda lime -
410S11 $283.15 each 150 C 2205 Duplex NPT 1" Soda lime -
410S12 $288.05 each 150 C 2205 Duplex NPT 1-1/4" Soda lime -
410S13 $299.25 each 150 C 2205 Duplex NPT 1-1/2" Soda lime -
410S14 $381.23 each 150 C 2205 Duplex NPT 2" Soda lime -
413S05 $214.80 each 150 C 2205 Duplex NPTF 1/4" Soda lime -
413S06 $231.09 each 150 C 2205 Duplex NPTF 3/8" Soda lime -
413S07 $249.15 each 150 C 2205 Duplex NPTF 1/2" Soda lime -
413S09 $264.70 each 150 C 2205 Duplex NPTF 3/4" Soda lime -
413S11 $298.87 each 150 C 2205 Duplex NPTF 1" Soda lime -
413S12 $303.54 each 150 C 2205 Duplex NPTF 1-1/4" Soda lime -
413S13 $345.94 each 150 C 2205 Duplex NPTF 1-1/2" Soda lime -
413S14 $387.90 each 150 C 2205 Duplex NPTF 2" Soda lime -
This is the full technical specification: http://quartz.com/gedata.html UV cutoff is at < 160 nm

Encole also manufactures custom sight glasses with higher optical properties, using Suprasil 311 or Corning 7980.