1. Definition and core structure
Full-lug butterfly valve is a butterfly valve that realizes pipeline connection through symmetrical lug structures on both sides of the valve body flange. Its core feature is that it adopts clamp-type installation and uses stud bolts to penetrate the valve body lugs and the pipeline flange for fixing. This design allows the valve to maintain stable connection under high pressure and high vibration conditions, and simplifies the installation and maintenance process.
2. Key technical characteristics
Lug structure design
Symmetrical lugs on both sides: There are raised lugs on both sides of the valve body, which are rigidly connected to the pipeline flange by bolts to enhance shear resistance and are suitable for high-pressure scenarios (such as 6.4MPA grade); Three-dimensional eccentric seal: The butterfly plate adopts an eccentric oblique conical valve seat. When closing, the butterfly plate and the valve seat are pressed tighter and tighter, and the sealing performance is reliable and the friction is low.
Material adaptability
Valve body material: common cast steel, stainless steel (such as 304/316L), cast iron, etc., suitable for corrosive media (such as chemical acid and alkali) and high temperature environment (up to 300℃); Seal material: metal hard seal (such as cemented carbide) or soft seal (such as PTFE), meeting the wear and corrosion resistance requirements of different media.
3. Typical applications
| Industrial | Specific application scenarios | Advantages |
|---|---|---|
| Petrochemical | Crude oil and natural gas pipeline flow control | Excellent high pressure resistance and corrosion resistance |
| Water treatment | Sewage treatment system valve opening and closing and regulation | Compact structure, easy to operate |
| Electricity | Thermal power plant steam system medium isolation | High temperature resistance, reliable sealing |
4. Comparison of technical advantages
| Terms | Traditional flange butterfly valve | Full Lug Butterfly Valve |
|---|---|---|
| Connection reliability | Flange is easy to misalign | Bolts pass through lugs, strong vibration resistance |
| Installation efficiency | Flange holes need to be aligned | Clip-on installation reduces positioning time |
| Maintenance costs | Complex disassembly | Split structure makes it easy to replace parts |
5. Selection and installation points
Selection basis
Medium characteristics (corrosiveness, temperature), pressure level (refer to ANSI/ASME B16.34 standard) and diameter range (DN40-DN1000);
The drive mode can be manual, pneumatic (such as Lake brand pneumatic actuator) or electric, adapted to the needs of automation control.
Installation specifications
Ensure that the stud bolts are evenly pre-tightened to avoid unilateral force causing seal failure;
After installation, a sealing test (such as a water pressure test) is required to verify the fit between the valve seat and the butterfly plate