Triplexcentric butterfly valve

for isolating crucial pipeline parts

VTC line triple offset buttterfly valves

Triple eccentric butterfly valves are designed for tight shut-off with lamellar sealing consisting of metal and PTFE layers. These valves are commonly used in transmission pipelines and terminal facilities, providing reliable isolation and long service life under demanding operating conditions. The triple offset design minimizes seat wear and eliminates friction between seat and disc during operation making this valve type suitable for high-performance pipeline service in EPC projects.

Specification

Nominal size

4" - 48", DN 100-1000

Pressure ratings

class 150# - class 900#, PN 10-200

Materials

carbon steel (WCB), stainless steel, alloy steel

Actuating

manual, pneumatic, electric

Applicable standards

Design standard

API 609, ASME B16.34

Face to face dimension

ASME 16.10, EN 558

Flange standard

ASME 16.5, B 16.47, EN 1092

Butt welded ends

ASME 16.25

Pressure test

API 598, EN 12226

Technical information

Design and construction features

Technical sheets

VT11-DF - Triple offset butterfly valve carbon steel double flanged
VT12-DF - Triple offset butterfly valve stainless steel double flanged
VT11-BW - Triple offset butterfly valve carbon steel butt welded ends
VT12-BW - Triple offset butterfly valve stainless steel butt welded ends

Structural features of triple offset butterfly valve

OFFSET 1
The stem centerline is offset from the seat center, allowing the sealing ring to fully and uniformly contact the entire seat surface.
OFFSET 2
The stem centerline is offset from the pipeline to prevent interference during valve opening and closing.
OFFSET 3
The center line of the seat cone deviates from the center line of the valve to form an angle eccentric, so that during the opening or closing of the valve, any point between the sealing ring and the seat will quickly separate or contact, achieving true “zero-friction” between the sealing pair, greatly extending the service life of the valve.

Opening-closing principle

FRICTIONLESS MOVEMENT
The unique triple-eccentric structure enables the butterfly disc to achieve full-stroke frictionless rotation during the opening and closing process, eliminating all contact friction between the seal and the seat, and extending the service life of the valve.

ELASTIC SEAL GENERATED BY TORQUE
After the valve is closed, the sealing ring is radially compressed under the action of torque and cone angle. The elasticity of the sealing ring itself generates a reaction force that benefits the seal, pressing it tightly against the conical sealing surface of the seat, thereby achieving a two-way tight closure.

Sealing system

REPLACEABLE DISC SEALING
Lamellar sealing consisting of layers of Grahphit (PTFE) and stanless steel clamed with retinging ring enables sealing to be replaced.

HARD SEALING ON BODY
Hard facing sealing on body is welded to ensure long-life performance of valve in highly demanding conditions

Type of triple offset butterfly valves

DOUBLE FLANGED TYPE
The valve has flanges on both ends and is bolted directly between two pipeline flanges, providing a rigid, leak-tight and easily removable connection.

WAFER TYPE
The valve is installed between two pipeline flanges using through-bolts, offering a compact and lightweight solution.

WELDED ENDS TYPE
The valve ends are permanently welded to the pipeline, creating a fully integral, leak-free connection suitable for high-pressure and critical services.