Product - NW Series

​​​​​​​Sanitation Line: Butterfly Valve​​​​

Our NW series of butterfly valves is characterized by a wafer-style body following the AWWA construction standard. The series combines years of experience and research, that results in longer service life, excellent performance, easy maintenance and interchangeability of components.

​Key features

  • Eccentric disc
  • Seat sealing
  • Monobloc body
  • Disc configuration to
    minimise pressure drop


  • Body
    The wafer-style one-piece body is designed in order to ensure maximum security and reliability (proven by finite element analysis). It has an extended valve neck enabling pipework isolation

  • Disc
    The disc configuration minimises pressure drop in totally open position. The entire perimeter of the sealing area is polished to provide providing total sealing in relation to the seat, ensuring low operating torque and less wear of the seal

  • ​Shaft
    The upper shaft transmits the rotation movement to disc by means of a torque plug, ensuring the product performance and safety. The interface dimensions in accordance with ISO 5211

Product Specification

Construction standard
AWWA-C504 standard wafer


Face to face
AWWA-C504 standard wafer
75 to 600mm


  • ​Replaceable seat
    The replaceable seat completely covers the body and consists of a rigid ring, on which the elastomer seat material is vulcanized preventing deformation, reducing actuation torque and increasing seat service life

  • ​Bushing
    Bronze bushing eliminates friction between shaft and body providing torque reduction

  • ​Actuation
    The body design and top flange allows the coupling of manual, pneumatic or electric actuation which will comply with ISO 5211

  • ​Finite analysis
    Project developed with the aid of software for finite elements analysis ensuring greater structural reliability to the design​

Elastomer / polyurethane
ASTM A-536 Cast Iron for Grade 65.45.12
ASTM A-351 Stainless Steel for Grade CF8M
ASTM A-536 Cast Iron for Grade 65.45.12
NBR (Buna N) ASTM D-2000
ASTM A-276 Stainless Steel for Grade 410
ASTM A-276 Stainless Steel for Grade 304

Typical dimensions


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Product - NW Series