Double eccentric butterfly valves
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Manufacturing Water Valves Industrial Valves Penstocks and Gates Radial Gates Special Applications BUTTERFLY Management System ISO 9001:2015 www.tuv.com ID9105084789

(PFA) 10,16,25,40 BAR - Body and disc in ductile iron 400 / 500 ISO 1083 / steel S275J - Stainless steel seat on the body AISI 304 L EN 1.4301 - Stainless steel shafts AISI 420 B EN 1.4021 - Brass bushing BS 1400 LG2 or composite - Gaskets on shafts by O-Ring NBR - Main seal by NBR O-Ring encapsulated on the disk. - Retaining ring in galvanized steel S275J - Inside screws in stainless steel AISI 304-A2 EN 1.4301 - Galvanized steel 8.8 external screws - Shaft and disk connection by stainless steel pins and steel keys. - Cast iron G25 - Face to face dimensions according to ISO 5752 – serial...

Butterfly valves Butterfly valves are used as isolating and regulating devices on aqueducts, waterworks, hydroelectric plants and nuclear plants. - Low pressure losses with valve completely open - Drop tight closure - Reduced overall dimensions - Simple construction and intrinsically reliable - Manually and electrically operated - Possibility to be used as a safety valve (positive safety valve able to close even in case of tampering) In addition to the above mentioned technical advantages there is a remarkable economical benefit as this valve is cheaper than other valves with same materials...

Anticorrosive protection As standards from ND 150 up to ND 1800 mm. in ductile iron the anticorrosive protection is produced on hot support by epoxy resins with 150 micron minimum thickness. Epoxy power is suitable for portable water according to specifications of most important European Certification agencies. As standard from ND 250 up to ND 4000 mm. made in S275J steal for industrial purposes, the anticorrosive protection is produced by means of a zinc flame-wire coating of 70-100 micron thickness after sandblasting grade SA 2 ½ and epoxy bicomponent spray with 100 micron minimum...

Hydraulic test All the Di Nicola butterfly valves are hydraulically tested to verify the conformity to ISO 5208 or EN 12266-1. Di Nicola butterfly valves are marked as follows: - Nominal Diameter ND in mm; - Nominal Pressure NP in bar; - Material according to UNI-ISO 1083-91; - Manufacturer’s trade mark; HYDRAULIC TESTS ON BUTTERFLY VALVES TEST REGULATORY ACCEPTABILITY SHELL TEST Valve capped at the ends Obturator slightly open No loss the side seals SEAT TEST Corked valve at one end shutter closed applied pressure from upstream BACK SEAT TEST Corked valve at one end shutter closed applied...

MANUALLY OPERATED BUTTERFLY VALVE H2 ELECTRICALLY OPERATED BUTTERFLY VALVE M1 Our firm reserves the right to make any technical changes without any notice to the client

Our firm reserves the right to make any technical changes

WELDED STEEL BUTTERFLY VALVES FLANGED TYPE SIZE L(AWWA) L(B.S.I.) A mm mm mm mm Our firm reserves the right to make any technical changes without any notice to the client.

DOUBLE AND TRIPLE ECCENTRICITY BUTTERFLY VALVE Double eccentricity The valve disk is carried by two stub shafts mounted in an eccentricity: Primary eccentricity advantages: - Better fastening of shafts to disk; - Seal made of a single piece; - Seal replaceable without removing the disk; - Reduced seal dragging on sealing seat; Double eccentricity Secondary eccentricity advantages: - Better detaching of sealing from seat; - Lower closing torque; Triple eccentricity The valve disk is carried by two stub shafts mounted in an eccentric position from the centerline of the disk. An additional...

Opening degree (%) where: P1= upstream pressure (mH2O) P2= downstream pressure (mH2O) Pa = absolute pressure (=10 mH2O) Pv = vapour pressure V = nominal velocity (m/s) g = gravity accelleration CAVITATION AREA WORKING AREA DOWNSTREAM PRESSURE > UPSTREAM PRESSURE

DIAGRAM OF WATER VELOCITY- Differential Pressure 200 max water velocity (m/s) Head loss through the butterfly valve: valve totally opened Nominal water velocity (m/s) - head loss (mH2O) m/s Our firm reserves the right to make any technical changes without any notice to the client.

CHART OF THE CALCULATION OF LOSSES DEPENDING ON THE SCOPE Our firm reserves the right to make any technical changes without any notice to the client.

KV DIAGRAM FOR THE THROTTLE VALVE WITH DOUBLE ECCENTRIC Kv (m3/h) 100000 Open Degree ΔP = pressure drop in bar Q = water flow in m3/h Kv = flow factor for the valve m3/h (diagram 1) The flow factor - Kv- is defined as the flow of water through a valve at 200 C in cubic meters per hour (m3 / h) with a pressure drop of 1 bar. It depends on the valve’s designed, diameter and opening angle of the disc. Our firm reserves the right to make any technical changes without any notice to the cl

HYDRAULIC ACTUATOR SINGLE AND DOUBLE EFFECT 14 Mechanical limit switch Hydraulic cylinder Protective tube Safety locks Proximity sensor TECHNICAL FEATURES cylinder specifications Dimensions Hydraulic circuit Cylin./ Stem ø mm Our firm reserves the right to make any technical changes without any notice to the clie

CONTROL DEVICES The butterfly valve can be equipped with various operating units of several utilizations and different requirements: - PVC tube protected with extension stem and manhole ; - Hydraulic power pack and electric cabinet; - Electric actuator; - Handwheel; - Steam square cap and operating key; - Floor pillar with handwheel and extension stem; Locking device (Up to 4 devices) Extension spindle with joint Stem square cap Handwheel Lever and counterweight Single and double oleodinamic actuator actuator Electric actuator Worm gear Pneumatic actuator Butterfly valve Our firm reserves...

HYDRAULIC ACTUATOR LEVER AND COUNTERWEIGHT ITE Hydraulic cylinder Cylinder port Pivot foot Mechanical limit switch Our firm reserves the right to make any technical changes without any notice to the client.

Safety butterfly valves with lever and counterweight Safety butterfly valves are used for the following purposes: - Shut off the pipeline on pumping plans or penstocks in case of failure of electric power in order to avoid backflow towards the pump; - Keep low the damages that may be caused by water excess velocity into pipelines by supplying a hydroelectric turbine in case of malfunctioning of the turbine, or more frequently, following a pipe fracture due to earthquakes or crumbling movements. Constructive characteristics Safety butterfly valves are made of: - A standard butterfly valve...