Sight glass for industrial applications Type 591

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The Flow sight glass Type 591 is a welded, three-viewing-window sight glass for installation between flanges according to DIN EN 1092-1. It is suitable for liquid and gaseous media and for high working pressures up to 400 barg. The third viewing window enables illumination of the flowing medium and integration of measurement or camera systems for improved process observation.

Nominal sizes (DN)

• 50
• 65
• 80
• 100
• 125
• 150
• 200

Nominal pressure (PN)

• 16
• 40
• 63
• 100
• 160
• 250
• 320
• 400

Temperature options

• 80 °C
• 130 °C
• 150 °C
• 175 °C
• 180 °C
• 200 °C
• 280 °C
• 300 °C
• 320 °C

Options / Accessories

• Wiper SGW with PTFE or silicone wiper blade
• LED light for Ex and non-Ex areas
• FEP or Halar® coating
• Mica protection discs
• Double glazing (Type 591D)
• Special constructions / custom manufacturing

Dimensions / drawing (summary)

• Total length (BL): DIN EN 558-1 FTF 2 (standard, if constructively possible)
• Length of assembly (AL): according to order confirmation / customer drawing
• Flange dimensions: DIN EN 1092-1
• Free view (D1) by DN (PN 16 reference):
  • DN 50: D1 = 100
  • DN 65: D1 = 150
  • DN 80: D1 = 175
  • DN 100: D1 = 175
  • DN 125: D1 = 175
  • DN 150: D1 = 175
  • DN 200: D1 = 240
• Free view (D2) by DN (PN 16 reference):
  • DN 50: D2 = 55
  • DN 65: D2 = 70
  • DN 80: D2 = 83
  • DN 100: D2 = 107
  • DN 125: D2 = 132
  • DN 150: D2 = 159
  • DN 200: D2 = 207
• Note: Dimensions correspond to nominal pressure level PN 16; other pressure levels may differ.

Characteristics / technical specifications

• Brand: ACI Industriearmaturen GmbH
• Commercial model designation: Type 591
• Working pressure: up to 400 barg (multiple PN levels available)
• Suitable media: liquid and gaseous media
• Nominal sizes: DN 50 – DN 200
• Nominal pressure ratings: PN 16, 40, 63, 100, 160, 250, 320, 400
• Standard glass: borosilicate glass (standard up to 280 °C)
• Higher temperature capability: with mica protective disk up to 300 °C or up to 320 °C in combination with MAXOS® safety sight glasses (DIN 7080)
• Connection: flange connections according to DIN EN 1092-1; standard lengths according to DIN EN 558-1 (FTF 2)
• Sealing: flat gaskets from a wide range of materials (including PTFE (Teflon®), NBR, novaphit® MST-XP, KlingerSil® C4400 and many branded seals) — over 50 sealing materials available
• Available options: wiper, LED lights, FEP/Halar® coatings, mica protection discs, double glazing (591D), special/custom constructions
• Applications: retrofit into existing systems thanks to standard lengths; custom manufacturing possible