Extended Stem Butterfly Valve

An extended stem butterfly valve is a specially designed butterfly valve with lengthened valve stem.It is mainly used for long-distance operation,heat insulation,cold insulation,buried pipeline,and high/low temperature working conditions.The extended stem structure effectively isolates the operating handle/gearbox from the high temperature,low temperature,deep buried and corrosive environment of the pipeline medium,ensuring stable operation,safe operation and long service life of the valve.

Working Principle

The extended stem structure transfers the opening and closing torque from the valve disc to the upper operating end through the lengthened valve rod.

When the stem rotates,the butterfly disc inside the valve body rotates synchronously to realize pipeline opening,throttling and closing.

The extended stem prolongs the distance between the valve body and the operating mechanism,which avoids heat conduction,low temperature frostbite,corrosion damage and inconvenient operation caused by harsh pipeline environment.

Main Materials

Valve Body:Ductile iron/Cast iron/Stainless steel

Butterfly Disc:Ductile iron,stainless steel with epoxy coating

Extended Stem:410/304/316 stainless steel,high rigidity,anti-bending,anti-corrosion

Seat Seal:EPDM,NBR,fluororubber(FKM)

Operating Parts:Handle,worm gear box,electric actuator,pneumatic actuator

Key Features

Extended Stem Design

Customizable stem length according to engineering requirements,suitable for buried pipeline,heat insulation layer,wall penetration and deep installation occasions.

Excellent Heat&Cold Insulation Performance

Effectively blocks high temperature heat transfer and low temperature cold conduction,protects the actuator,bearing and packing parts from thermal aging and freezing damage.

Strong Corrosion Resistance

Stainless steel extended stem prevents rust,corrosion and jamming under underground humid,muddy and corrosive environments.

Convenient Operation&Maintenance

Operating end is exposed above ground or outside the insulation layer,easy for daily opening,closing,adjustment and maintenance without digging or dismantling insulation structure.

Stable Structure&High Safety

High-strength lengthened stem with anti-loosening structure,no deformation,no deviation during long-term operation,reliable sealing performance.

Wide Adaptability

Compatible with various drive modes,can be matched with manual,worm gear,electric and pneumatic actuation.

Technical Specifications

Body Material:Ductile Iron,Cast Iron,SS304,SS316

Disc Material:Ductile Iron,Stainless Steel

Extended Stem Material:Stainless Steel

Seal Material:EPDM,NBR,FKM

Size Range:DN50~DN2000

Working Pressure:PN6,PN10,PN16

Stem Length:Customizable extended length as per customer requirement

Connection Type:Wafer type,Flange type,Lug type

Working Temperature:-40℃~220℃

Drive Mode:Handle operated,Worm gear,Electric,Pneumatic

Applications

Buried underground water supply and drainage pipelines

Heat supply and thermal pipeline systems with thick insulation layers

Low-temperature cold water and cryogenic pipeline engineering

Wall-through pipeline installation projects

Municipal water conservancy,sewage treatment engineering

Industrial pipeline with high temperature,deep buried and harsh working conditions

Pipeline systems requiring remote manual operation