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Eccentric Segmental Ball Valve

image of Eccentric Segmental Ball Valve


The PROVAL segmental ball is an eccentric plug, high performance rotary control valve. Designed for use in a wide variety of applications ranging from low pressure, high “Cv” to slurry and pulp services, to oil and gas services. The PROVAL segmental ball can handle shut-off pressure drop up to 50bar. Operating temperatures can from -50°C to 450 °C.

The PROVAL segmental ball control valves consist of a straight valve body with less flow resistance and separable plug with flow guide that rotates eccentric.



· Large capacity
The Proval segmental ball valves provide larger valve capacities than those of the globe valves.
For example, an 8-inch Proval segmental ball valve provided by a 10-inch globe valves.
· Large capacity
The rangeability of Proval segmental ball valves is 100:1, much larger than that of butterfly valves and that (50:1) of globe valves. Thus, each of Proval segmental ball valves can cover a very wide flow range.
· Excellent shut-off performance
The Proval segmental ball valves render excellent shut-off performance -0.01% of the valves for standard valves for complete shut-off (ANSI B16, 104 Class VI) for valves incorporated with a Teflon seat (=soft seat).
· Compact & Lightweight
The Proval segmental ball valves are more compact and lightweight than globe valves of corresponding sizes and can be installed in various directions, thereby greatly facilitating installation and maintenance.
· Dirty and gummy service
The Proval segmental ball valves employ an open yoke type plug and a through type valves body which ensures no entrapped flow. Thus, they can be used for dirty and gummy service as well as for regular service.


Model No. YADS-122E1 Series, YABS-122E1 Series
Valve Type Diaphragm & Cylinder operated segmental ball valve.
BODY Valve Size (mm) 25 40 50 65 80 100 125 150 200 250 300 350 400 450 500
(inch) 1 1 ½ 2 2 ½ 3 4 5 6 8 10 12 14 16 18 20
Pressure Rating ANSI 150# ~ 600# / JIS 10K ~ 30K / JPI 150# ~ 600# / PN 6bar ~ 40bar
End Connections Flanged end: R.F/ F.F/ WAFER
Body Materials A216-WCB, A351-CF8, CF8M, CF3, CF3M
Soft seat -50°C to +180°C
Metal seat -50°C to +450°C
Guide Top & Bottom guide
Gland Packing V-PTFE, PTFE yarn, Graphite yarn
Gland Type Bolted gland
Bonnet Body integral type
Gasket VITON O-ring, PTFE, SUS316 + Graphite spiral wound, Other alloy steels.
Painting Color Standard is silver. In the case of stainless steel, flange is not painted.
Flow Direction Direct
Trim Materials Metal trim SUS304 (STL.), SUS316 (STL.), SUS316L (STL.), Alloy-TiC
Soft trim PTFE, Carbon PTFE, Glass-filled PTFE
PERFORMANCE Valve Action Reverse action, Direct action
Differential Pressure
Rated Cv Value See “FLOW CHARACTERISTICS” page 7
Flow Characteristics See “FLOW CHARACTERISTICS” page 7
Rangeability 100:1
Allowable Seat
Leakage Ratio
Metal Seat ANSI B16. 104 Class IV
※Tight shut off - ANSI B16. 104 Class V
Soft trim ANSI B16. 104 Class VI
Action Accuracy Hysteresis (With positioner) max. 2% F.S. (only “DB” type actuator)
Linearity (With positioner) max. ±2% F.S. (only “DB” type actuator)
ACTUATOR Model DB-240, DB-300, DB-400, DB-520 B1S(R) ~ R7S(R)
Actuator Type Single-spring type diaphragm operated Rotary cylinder type actuator
Actuator Size
(diaphragm & cylinder size)
Ø240 ~ Ø520 Ø70 ~ Ø300
Operating Angle 60°, 90° 90°
Air Supply Pressure
kPa (kgf/cm²G)
160 (1.6), 320 (3.2) 400~700 (4.0~7.0)
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: E.P.D.M. Piston O-ring: N.B.R or VITON
Air Connection Rc 1/4 Rc 1/4 ~ Rc 3/8
Ambient Temperature -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]

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