Product Description

PRODUCT INTRODUCTION

• Core structure: Valve body, disc, stem, seat seal, manual drive mechanism (handle/worm gear)
• Working principle: Disc parallel to pipeline full open (minimum flow resistance); disc perpendicular to pipeline full closed (sealing surface fits tightly)

BUTTERFLY VALVE CLASSIFICATION

1. By Sealing Type (Core Classification)

• Sealing materials: EPDM, NBR, FKM, PTFE, rubber/PTFE-lined
• Features: Bidirectional zero leakage, good sealing, low torque, low cost
• Application: Normal temperature and low pressure (-20120, PN1.6MPa), clean or weakly corrosive media

• Sealing materials: Hard alloy, stainless steel, Stellite overlay
• Features: High temperature resistance, wear resistance, higher pressure resistance, long service life, slightly higher leakage rate
• Application: High temperature and high pressure (-40650, PN6.4MPa), media with particles or steam

2. By Structural Offset Form

• Stem, disc and valve body centers coincide; the sealing surface is an annular extrusion seal
• Advantages: Simple structure, low cost, good bidirectional sealing
• Disadvantages: High wear on sealing surface, high torque, not suitable for high pressure

• Stem center deviates from disc center, reducing friction between disc and seat
• Application: Low-pressure, frequent opening/closing scenarios

• Stem offset + disc offset; disc quickly disengages from seat during opening/closing, low torque, long service life
• Application: Medium-low pressure, large diameter, frequent operation

• Triple offset of stem, disc and sealing cone; sealing surface is inclined conical, no friction, reliable sealing, high pressure resistance
• Application: Medium-high pressure, high temperature, harsh working conditions (such as steam, oil products)

3. By Manual Drive Mode

• Directly rotate the handle 90 to open/close; status is intuitive (parallel open, perpendicular closed)
• Application: DN300, low pressure, quick operation scenarios

• The handle drives the worm gear to reduce speed, amplifies torque and makes operation labour-saving
• Application: DN250, high pressure, large diameter, scenarios requiring precise regulation

4. By Valve Body Material

• Cast iron (HT200/HT250): Low cost, water supply and drainage, sewage
• Ductile iron (QT450): High strength, municipal pipe networks, HVAC
• Carbon steel (WCB): Medium-high pressure, steam, oil products
• Stainless steel (304/316): Corrosion resistance, chemical, food and pharmaceutical industries
• PTFE/rubber-lined: Strongly corrosive media (acid-base, organic solvents)

TECHNICAL SPECIFICATIONS

TEMPERATURE AND MEDIA

• Soft seal: -20120 (EPDM); -40200 (PTFE)
• Hard seal: -40650 (stainless steel/hard alloy)
• Applicable media: Water, sewage, air, steam, oil products, gas, weak corrosive liquids, slurries, etc.

PRODUCT FEATURES

1. Core Advantages

• Compact and lightweight: Length is 1/41/8 of flanged valve, weight is 1/31/5, saving space and support cost
• Quick opening/closing: 90 rotation completes switch operation, high efficiency
• Low flow resistance: Only the disc thickness is resistance when fully open, low pressure loss
• High cost performance: Manufacturing cost is 50%60% of a flanged valve, with simple maintenance
• Flexible installation: Can be installed at any angle, sealing rings are easy to replace

2. Limitations

• Cannot be used as pipe end valve (requires flange support on both sides)
• Sealing stability is average under high pressure (PN4.0) and large differential pressure conditions
• Both ends of bolts need to be loosened for disassembly, maintenance requires pipeline shutdown
• Soft seals are not resistant to high temperature and hard particle media