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SISTO-20 Diaphragm valve
Diaphragm valve


Diaphragm valve to DIN/EN with flanged ends; shut-off and sealing to atmosphere by completely enclosed spiral-supported diaphragm; body with or without lining, position indicator with integrated stem protection. All moving parts are separated from the fluid by the diaphragm. Maintenance-free.
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Main Applications

  • Chemical industry
  • Homogenisation
  • Industrial recirculation systems
  • Nuclear power stations
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Technical Data

  • Nominal pressurePN 16
  • Max. nominal sizeDN 200
  • Max. allowed fluid temperature160 °C

Material number list – SISTO-20

32 products
NameNominal pressureNominal size InletWeightMaterial numberPrice
SISTO-20 1.4409-EPDM Rp1 (DN25) PN162.5 KilogramM284A003
upon request
SISTO-20 1.4409-EPDM Rp1 1/2 (DN32) PN162.5 KilogramM284A004
upon request
SISTO-20 1.4409-EPDM Rp1 3/4 (DN40) PN163 KilogramM284A005
upon request
SISTO-20 1.4409-EPDM Rp1/2 (DN15) PN160.5 KilogramM284A001
upon request
SISTO-20 1.4409-EPDM Rp2 (DN50) PN165 KilogramM284A006
upon request


  • Reliable sealing to atmosphere and absolutely tight shut-off
  • The diaphragm provides absolutely tight shut-off as well as hermetic sealing to atmosphere and of all operating elements.
  • Maximum service life and pressure limit

Technical Data

  • FunctionShut off/control flow
  • Connection typeInternal-thread connection, Flange, Butt weld ends, Socket weld ends
  • Design concept DriveWith electric actuator, With handwheel, With pneumatic actuator
  • Casing materialEN-GJS-400-18-LT, GX5CRNIMO19-11-2
  • Nominal pressurePN 16
  • Max. nominal sizeDN 200
  • Min. nominal sizeDN 15
  • Max. allowed fluid temperature160 °C
  • Min. allowed fluid temperature-20 °C

Sectional Drawings


TitleFormatSizeLast change
Declaration of conformity (8630.8507_EN)PDF0.158/5/2021
TitleFormatSizeLast change
ATEX-Declaration by the manufacturer (8630.8501_EN)PDF0.564/19/2021
TitleFormatSizeLast change
Operating Manual (0570.821_EN)PDF3.437/17/2021
TitleFormatSizeLast change
Type series booklet SISTO-20 (8643.1_EN)PDF2.488/11/2021
Type series booklet SISTO-20M (8638.12_EN)PDF0.264/19/2021

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