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High Performance Butterfly Valve

image of High Performance Butterfly Valve


The design of PROVAL YADB-122E1, YABB-122E1 Series is a high-performance butterfly valve designed to control for difficult-to-control fluids impossible with conventional universal type of butterfly valves. Featuring a self sealing seat ring, double eccentric disc, and a choice of three seat rings, the YADB-122E1 Series far surpasses ball valves and gate valves - even fluids such as corrosive slurry and high-pressure steam can be perfectly sealed off.



· Self-sealing mechanism ensures a tight shut-off
As illustrated below, fluid pressure to the disc and seat ring ensures a secure seal. The higher the pressure, the better the sealing performance. The sealing performance remains uncharged even when the flow direction changes from one way to the other.
· Double eccentric disc ensures longer service life, low seating torque and leak-tight shut-off.
Since the stem is eccentric from the seat ring (as indicated by A and B), the disc has contact to the seat ring only when the valves is completely closed. Here are benefits from the double eccentric disc design.
  1. 1. Less wear of the seat ring offers longer service life of the seat ring.
  2. 2. When the disc closes, the disc pushes the seat ring outward and ensures perfect sealing.
  3. 3. Easy operation with less seating torque.
  4. 4. Easy replacement of the seat ring without removing the stem, thanks to the design of the stem not penetrating through the seat ring.
· Compact, lightweight, and cost-effective
Employing the thin wafer body, the YADB-122E1 series is significantly smaller and lighter than gate valves or ball valves, and piping works can be greatly simplified.
· Eccentric disc
- Extending seat service life
- Providing smooth and even touch
- Improving sealing
- Eliminating friction
- Reducing operating torque


Model No. YADB-122E1 Series, YABB-122E1 Series
Valve Type Diaphragm & Cylinder actuator operated high-performance butterfly valve.
BODY Valve Size (mm) 50 65 80 100 125 150 200 250 300 350 400 450 500 550 600 650 700 750 800 850 900 1000 1100 1200
(inch) 2 2 ½ 3 4 5 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 40 44 48
Pressure Rating ANSI 150# ~ 300# / JIS 10K ~ 20K / JPI 150# ~ 300# / PN 6bar ~ 25bar
End Connections FLANGES , WAFER , B.W
Body Materials A216-WCB, A351-CF8, CF8M, CF3M
Soft seat -45°C ~ +180°C (PTFE, RTFE) , # -196°C(PCTFE), +250°C(PEEK)
Metal seat Max 450°C (SUS304, SUS316, SUS316L)
Guide Top & Bottom guide
Gland Packing PTFE yarn, Graphite yarn
Gland type Bolted gland
Painting Color Standard is silver. In the case of stainless steel, flange is not painted.
Disc Characteristics Modify EQ %, Quick opening
Flow Direction Direct
PERFORMANCE Valve Action Direct action, Reverse action.
Differential Press.
Rated Cv Value See “FLOW CHARACTERISTICS” page 6, 7
Flow Characteristics See “FLOW CHARACTERISTICS” page 6
Rangeability 20:1
Allowable Seat
Leakage Ratio
Soft Seat ANSI B16. 104 Class VI
Metal Seat ANSI B16. 104 Class III ※ ANSI B16.104 CLASS Ⅳ
Hysteresis (Without positioner) max. 5% F.S. (With positioner) max. 2% F.S.
Linearity (Without positioner) max. ±6% F.S. (With positioner) max. ±2% F.S.
ACTUATOR Model DB-240, DB-300, DB-400, DB-520 B0S(R) ~ R12S
Actuator Type Single acting diaphragm operated. Rotary cylinder actuator (Double, Single)
Actuator Size Ø240 ~ Ø520 Ø50 ~ Ø400
Max. Stroke (mm) 60°, 90° 90°
Supply Air Pressure
kPa (kgf/cm²G)
160 (1.6), 320 (3.2) 500~700 (5.0~7.0)
Spring Range
kPa (kgf/cm²G)
60~100 (0.6~1.0), 120~200 (1.2~2.0) Single: 200~350 (2.0~3.5)
Double: 400~400 (4.0~4.0)
Materials Diaphragm: EPDM Piston O-ring: N.B.R or VITON
Air Connection Rc 1/4 Rc 1/4 ~ Rc 1
-20°C ~ +70°C (※-20°C ~ +100°C) -10°C ~ +70°C (※ 0°C ~ +100°C)
Painting Color Standard is Cobalt Blue(Munsell No : 2.5 PB3/10 ) [ Request other color ] Standard is red. [ Request other color ]

(1) Valve performance is represented under the condition of standard packing (PTFE yarn).
(2) ※: Manufactured and attached as according to customer’s order.