China Suppliers Factory Concentric Resilient Seated Lug Butterfly Valve with EPDM Seal for DN40-DN600
| Valve Type: | Lug butterfly valve | Structure: | Concentric |
| Standard: | EN593 | Workmanship: | Investment casting |
| Sealing direction: | Bidirectional | Sealing grade: | Zero leakage |
| Temperature: | -20°C<T<120°C | Operation: | Handle/Lever |

Handle
Various materials
Quick and precise opening and closing switches

Seal
EPDM seal, corrosion resistance, good sealing performance, good resilience, and aging resistance

Shell
Thickened valve body, enhanced impact resistance, and extended service life

Disc
Pinless disc, eliminate leakage and ensure durability
Characteristics
The lug butterfly valve balances the compactness of the clamp valve with the stability of the single-sided flange connection. One end of it has an integral flange (lug), and the other end is a clamp type. During installation, only one side needs to be connected to the pipeline flange, and the other side needs to be fixed with a nut. This design eliminates the need for relying on flange alignment at both ends like clamp valves, making installation more convenient and reliable. It is particularly suitable for pipeline ends or situations that require frequent disassembly and maintenance, while avoiding stress issues that may arise from long bolt penetration. It is a preferred solution that balances space and stability requirements.
Advantages
- Single side flange connection: One end of the valve body comes with an integral flange (lug), and the other end is a clamp type. During installation, simply fix the protruding ear end to the pipeline flange with bolts and tighten the clamping end with nuts.
- When maintenance or replacement of valve internal components is required, only one side of the connection needs to be disassembled to remove or rotate the valve as a whole from the pipeline. Maintenance operations are more convenient and efficient than double flange valves.
- It can better withstand the stress caused by vibration and thermal expansion from the pipeline, as well as the self weight of the valve, reducing the adverse effects of pipeline deformation on the valve sealing surface and helping to maintain the stability of sealing performance in the long term.
- Very suitable for occasions that require frequent opening and closing or adjustment, and have requirements for installation reliability, such as circulating water systems, fire protection systems, ventilation systems, as well as atmospheric or medium low pressure pipelines in industries such as chemical and power.
Packing
Standard export wooden case packaging
Application Scenarios
The lug butterfly valves are widely utilized across industrial, municipal, and specialized systems, leveraging their robust lug connection, balanced compactness and reliability, bidirectional sealing capability, and compatibility with medium-low to medium-high pressure conditions. Their unique design makes them ideal for scenarios requiring frequent maintenance, stable sealing, or adaptability to diverse media.
Frequently Asked Questions (FAQ)
What is a lug butterfly valve and how does it work?
A lug butterfly valve features threaded inserts (lugs) on the outside of the valve body. It is installed between two pipe flanges using separate sets of bolts for each flange. This allows one side of the piping system to be disconnected without disturbing the other side.
Can this lug butterfly valve be used for dead-end service?
Yes, due to its threaded lug design, this valve is highly suitable for dead-end service. It can be bolted securely to one side of the pipeline, allowing the downstream piping to be removed safely for maintenance while the valve remains closed and holding back pressure.
What are the advantages of the pinless disc design?
The pinless disc design eliminates the need for pins through the disc and stem, which minimizes potential leak paths, reduces wear, increases mechanical strength, and ensures a cleaner flow path with longer durability.
What media is the EPDM seal suitable for?
The EPDM seal is highly resistant to water, steam, diluted acids, alkalis, and ketones. It offers excellent resilience and aging resistance within the temperature range of -20°C to 120°C. It is not recommended for petroleum-based fluids.
What does bidirectional sealing and zero leakage mean?
Bidirectional sealing means the valve can block media flow and seal effectively in both directions of the pipeline. Zero leakage indicates that the valve achieves complete shutoff without any fluid passing through when fully closed, complying with strict industrial sealing grades.
















