Sight glass for industrial applications Type 620

sanitaryfor hygienic applicationsstainless steel

The Tubular sight glass Type 620 provides a full 360° view of the process medium through a borosilicate glass cylinder encased between two flanges. It is engineered for hygienic and industrial applications and is available in multiple materials, pressure ratings and sizes.

Key product features

• 360° view via borosilicate glass cylinder (Borosilicate glass 3.3 according to DIN ISO 3585).
• Flange connections according to DIN EN 1092-1; standard flanges in stainless steel 1.4571 (316Ti); optional P265GH or special alloys (Hastelloy®, duplex steels, other high-performance alloys) on request.
• Designed to be nearly dead-space-free through precise coordination of flange, gasket and glass—suitable for hygienically demanding processes.
• Wide range of sealing materials available (from classic fiber seals to PTFE (Teflon®), NBR, novaphit® MST-XP, KlingerSil® C4400 and more).
• Mechanical protection options: impact protection cover in PETg or perforated plate; custom total lengths available.
• Suitable for liquid and gaseous media; overview: max. 16 barg (depending on nominal size), heat resistant up to 300 °C, nominal sizes DN 15 - DN 300, custom manufacturing possible.

Construction / main components

• Nuts
• Flange
• Threaded rod / bolts
• Borosilicate glass cylinder
• Gasket (selectable from a wide material range)

Available options and temperatures

• Nominal pressure options: PN 10, PN 16.
• Temperature ratings (examples / selectable): 80 °C, 130 °C, 150 °C, 175 °C, 180 °C, 200 °C, 280 °C, 300 °C.
• Impact protection covers and custom total lengths on request.

Nominal sizes (DN)

• 15, 20, 25, 32, 40, 50, 65, 80, 100, 125, 150, 200, 250 (special construction on request), 300 (special construction on request)

Dimensions by nominal size (selected values)

• DN 15 — K: 65 mm; DF: 41 mm; D: 95 mm; PS: 16 bar
• DN 20 — K: 75 mm; DF: 54 mm; D: 105 mm; PS: 16 bar
• DN 25 — K: 85 mm; DF: 64 mm; D: 115 mm; PS: 16 bar
• DN 32 — K: 100 mm; DF: 74 mm; D: 145 mm; PS: 16 bar
• DN 40 — K: 110 mm; DF: 84 mm; D: 150 mm; PS: 16 bar
• DN 50 — K: 125 mm; DF: 98 mm; D: 175 mm; PS: 16 bar
• DN 65 — K: 145 mm; DF: 118 mm; D: 195 mm; PS: 10 bar
• DN 80 — K: 160 mm; DF: 134 mm; D: 200 mm; PS: 10 bar
• DN 100 — K: 180 mm; DF: 154 mm; D: 225 mm; PS: 10 bar
• DN 125 — K: 210 mm; DF: 184 mm; D: 250 mm; PS: 8 bar
• DN 150 — K: 240 mm; DF: 208 mm; D: 295 mm; PS: 7 bar
• DN 200 — K: 295 mm; DF: 264 mm; D: 345 mm; PS: 5 bar
• DN 250 (special) — K: 350 mm; DF: 320 mm; D: 400 mm; PS: 4 bar
• DN 300 (special) — K: 410 mm; DF: 370 mm; D: 460 mm; PS: 4 bar

Technical specifications

• Model / type: Type 620
• Glass: Borosilicate glass 3.3 (DIN ISO 3585)
• Standard flange material: stainless steel 1.4571 (316Ti); alternatives: P265GH; special alloys on request (Hastelloy®, duplex, …)
• Nominal sizes: DN 15 - DN 300 (special sizes/lengths on request)
• Nominal pressure: PN 10 / PN 16 (max. 16 bar for smaller DN, see dimension table)
• Max. temperature resistance: up to 300 °C (depending on configuration)
• Sealing: wide selection (>50 sealing materials) including PTFE (Teflon®), NBR, novaphit® MST-XP, KlingerSil® C4400, fiber materials
• Options: impact protection covers (PETg or perforated plate), custom total lengths, custom materials and alloy executions