G CCI DRA Applications

Solve the Application ... cavitation bubbles form here, flashing occurs flashpoint P1 V1 Pv inlet velocity pressure V2 outlet velocity P2 outlet press...

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CCI DRAG® 100DSV for Spraywater Control Applications

DRAG® technology for severe service spraywater applications.

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 





Save Energy

The control of steam temperatures is of vital importance for safe, reliable

Improve Heat Rate Efficiencies

control valves are the final control elements in the control of the Superheat &

Stop Costly Maintenance Cycles

control maintains the throttle temperature at the set point resulting in an

Solve the Application with DRAG® Technology



and efficient operation of a thermal power plant. The attemperator spray Reheat temperatures. These are one of the critical components responsible for fine tuning the steam temperature control. A well tuned steam temperature efficient turbine operation. Attemperator Spraywater Valve Requirements Provide precise quantity of spray water in response to the control circuit demand over the entire load range. 

Operate at high pressure drops (up to 3500 psi or 240 bar) without damaging the trim components.



Consistent and reliable operation.



Tight shutoff to prevent damaging effects to the valve or to the downstream equipment such as the steam turbine and HP piping.

CCI DRAG® 100DSV for Spraywater Control Applications

Reheater

Consequences of Attemperator Spraywater Valve Problems

Reheater Spray Control Valve



Heat Rate Losses. Leaking spray water valves result in lowering the throttle steam temperature. The lower temperatures affect the heat rate

H.P. Turbine

appreciably. Additional heat input is required in the boiler to keep the

I.P. Turbine

throttle steam temperature at set point.

Secondary Superheater

 Primary Superheater

Temperature Control Problems. Poor steam temperature control also affects the HP steam piping and steam turbine. A change of 34-40 F

Superheater Spray Control Valve

(19-22 C) corresponds to a change of about 1% in heat rate at pressures above 1800 psi (124 bar). 

High Maintenance Costs. Frequent trim replacement or maintenance cycles due to trim erosion damage.

Economizer Area of Boiler Deagrator Feedwater Regulator Valve

Boiler Feedpump

Symptoms of Attemperator Spraywater Valve Problems

Condensate Pump

DA Level Control Valve

 Hot Well

Figure 1: An example of a typical spraywater system schematic. The CCI 100DSV DRAG® valve is engineered to exceed the demands of these severe service applications.

Erosion damage. Caused by insufficient number of trim stages and excessive trim velocities.



Cracking or fatigue failures of valve stems. Typically caused by high trim velocities and subsequent trim vibration and fatigue failure.



Operation of an upstream isolation valve to block the control valve leakage.

Let CCI’s DRAG® 100DSV valve provide the solution!

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Vvc P1 inlet pressure

DRAG® Velocity control protects valve components and ensures reliable system performance! Vvc

High trim exit velocities are responsible for erosion damage in control valves Vvc

(erosion is proportional to the 3rd or 4th power of velocity). The CCI DRAG® valve eliminates trim and body damage caused by erosion by incorporating

V1 inlet velocity Pvc Pv flashpoint

V2 outlet velocity

multiple tortuous flow paths designed to limit the trim exit velocities. Each

P2 outlet pressure

flow path has a series of turns which break up the pressure drop across the valve into multiple stages. The flow path has expanding passages to reduce

Pvc

exit fluid velocity.

Pvc

cavitation bubbles form here, flashing occurs

Figure 2: Typical control valve. The high fluid velocity and low number of pressure reducing stages combine to produce insufficient stages to protect trim from cavitation erosion.

CCI DRAG® 100DSV for Spraywater Control Applications

P1 pressure

CCI spray valves meet or exceed the control valve fluid velocity limits set by ISA Guide, “Control Valves, Practical Guides for Measurement and Control.” Velocity (H20) Service conditions

ft/s

m/s

Continuous service single phase fluids

100

30

Cavitating & multi-phase fluid outlet

75

23

How many pressure reducing stages are required? V1

V2 outlet velocity

inlet velocity

P2 outlet pressure

Pv flashpoint

Figure 3: The DRAG® solution. The fluid velocities are kept low and a high number of pressure reducing stages ensure a controlled letdown of the fluid pressure.

Delta P

Fluid velocity vs. stages of pressure drop

Recommended velocity / turns

Psi

1 stage ft / sec

3 stages ft / sec

velocity ft / sec

turns

600 – 100

155

105

100

4

1500 – 100

259

172

100

10

2400 – 100

331

233

100

12

441

302

100

16

4200 – 100

Example: ambient temperature water

Accurate control and reliable operation at all flow conditions with the CCI DRAG® disk stack The DRAG® spray valve disk stack features a modified equal percentage trim characteristic providing very fine temperature control. The disk stack uses disks with more pressure letdown stages near the seat end of the trim (up to 20 stages), and fewer stages near the full-open end of the trim. This provides critical protection of the seat ring while allowing superior temperature control throughout stroke of the valve. Independent and isolated flow paths are utilized to eliminate short circuits between the flow paths. Reliable Long Term Shutoff The DRAG® spray valve uses a hard seat, which resists trash cutting, and a very high seat loading to provide reliable and repeatable long-term shutoff for Figure 4: CCI 100DSV multi-path, multistage trim designs are characterized to provide optimal valve performance at all flow conditions.

very high pressure differentials. The actuator is sized to provide a minimum seat ring loading of 500 lbf per circumferential inch (9 kg/mm). The DRAG® velocity control trim design protects the seat ring and plug surfaces from cutting or pitting due to erosion.

CCI’s new attemperator Spraywater control valve solution.

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Stem Packing Multiple teflon packing with graphite guide spacer.

Top Entry Design Minimize service time, no trim parts are welded or screwed into the valve.

Gasket Seal Bonnet 2500 ANSI design.

Spindle Inconel 718 Multi-stage DRAG® control element Disk Stack

Limits velocity, control vibration and erosion. Provides superior control compared to seatthrottling trim.

CCI DRAG® 100DSV for Spraywater Control Applications

Provides superior control compared to seat-throttling trim.

Easy-to-Service-Seat No welding or grinding. Trim can be inspected, repaired or replaced quickly and with minimum effort. Class V Shutoff Metal seat standard.

Valve Performance Characteristics (% Cv vs. % Stroke) Valves are custom characterized to accommodate a wide range of variables.

Modified Equal Percentage

Equal Percentage

Use this checklist to evaluate the benefits of the DRAG® 100DSV Spraywater design.

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Benefits 1

DRAG® Velocity Control Protects Valve Trim. Up to 20 stages used to limit trim exit velocity to 100 fps or less. Eliminates erosion and cavitation damages.

2

Improve Heat Rate Efficiencies. The CCI spray valve minimizes lost energy through leakage and lost production which results in significant cost savings.

3

Reliable and Repeatable Long Term Shutoff Eliminates Leakage. Actuator is sized to provide 500 PLI or more.

CCI DRAG® 100DSV for Spraywater Control Applications

Metal seat ring is used to resist trash damage. The DRAG® velocity control design protects trim from damage. Eliminating spray water leakage prevents excess cooling of main steam and conserves fuel.

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Improve Temperature Control. Equal-percentage trim characteristics custom-engineered to meet your plant specifications combined with a long stroke and high actuator resolution to improve control.

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Reduce Maintenance Costs. Costly and frequent maintenance procedures are eliminated by DRAG® velocity control, actuator sizing and seat ring design. Erosion is eliminated.

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Easy to Service Design. Top entry design minimizes service time, and no welding or inline machining required.

DRAG® 100DSV

Competitors

Technical specifications and materials.

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Table 1: DRAG® 100 DSV Spraywater Valve Materials

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6 8 5 3

CCI DRAG® 100DSV for Spraywater Control Applications

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Components

Item No.

Materials of Construction

Body

1

A216 WCB

Bonnet

2

A182-F22

Seat Ring

3

316 SS

Spindle

4

Inconel 718

Disk Stack

5

Inconel 718

Balance Seal

6

Glass Filled Teflon

Stem Packing

7

Glass Filled Teflon

Gasket

8

Flexitalic® (Graphite/Stainless Steel)

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Table 2: DRAG® 100 DSV Spraywater Valve Technical Specifications

Customs designs available to meet your C v and piping requirements. Please contact a CCI representative for details.

Pressure Rating

ANSI 2500

Body Configuration

Angle or Globe (through)

Maximum Inlet Temperature

500 F (260 C)

Flow Direction

Over-the-plug (Flow-to-close)

Rangeability

100:1

Actuator

Spring Diaphragm with Positioner (3-15 PSIG) & Filter Regulator

Failure Mode

Fail Close- Standard (Optional fail in place)

Manual Override (Optional)

As shown

Integral Positional Transmitter (Standard)

Output signal = 4-20 mA

Integral I/P Transducer

Input signal = 4-20 mA

Limit Switches (Optional)

Double pole/Double throw

Shutoff

ANSI Class V with 500 PLI

Notes: 1. All buttweld end connections in accordance with ANSI B16.25 2. All socket weld end connections in accordance with ANSI B16.11 3. Use CCI’s Valsiz™ program for sizing and selection.

CCI DRAG® 100DSV for Spraywater Control Applications

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Table 3: DRAG® 100 DSV Spraywater Valve Outline Dimensions

Dimension in (mm)

Normal Size: 1 in

Normal Size: 2 in

Trim: 3/8 in, 5/8 in, 1 in

Trim: 1.5 in

Angle

Globe

Angle

Globe

A

4.0 in (102 mm)

-

5.8 in (146 mm)

-

B

-

8.0 in (203 mm)

-

11.5 in (292 mm)

C

37 in (940 mm)

D

3.1 in (79 mm)

44 in (1120 mm) -

4.6 in (117 mm)

-

Table 4: DRAG® 100 DSV Spraywater Valve Options Trim

3/8 in (9.5 mm)

Weight Rated CV

5/8 in (15.9 mm)

1 in (25.4 mm)

200 lbs (90 kg)

1.5 in (38.1 mm) 450 lbs (200 kg)

Reduced Trim

0.60

1.60

4.60

10.60

Full Trim

0.90

4.90

11.70

32.00

Valve Stroke

1.5 in. (38 mm)

2.5 in. (65 mm)

BW Connection Per ANSI B16.25

1 in, 1.5 in, 2 in, 2.5 in, 3 in SCH 40, 80, 160 & XXS

2 in, 2.5 in, 3 in, 3.5 in, 4 in SCH 40, 80, 160 & XXS

SW Connection Per ANSI B16.10

1 in, 1.5 in, 2 in, 2.5 in SCH 40, 80, 160 & XXS

2 in, 2.5 in SCH 40, 80, 160 & XXS

Throughout the world, companies rely on CCI to solve their severe service control valve problems. CCI has provided custom solutions for these and other industry applications for more than 40 years.

Sales and service locations worldwide. CCI World Headquarters— California Telephone: (949) 858-1877 Fax: (949) 858-1878 22591 Avenida Empresa Rancho Santa Margarita, California 92688 USA CCI Switzerland (Sulzer Valves) Telephone: 41 52 264 95 00 Fax: 41 52 264 95 01 Im Link 11, P.O. Box 65 CH-8404 Winterthur Switzerland CCI China Telephone: 86 10 6501 0350 Fax: 86 10 6501 0286 Room 567/569 Office Tower, Poly Plaza 14 Dongzhimen South Avenue Beijing 100027 China

CCI Korea Telephone: 82 31 980 9800 Fax: 82 31 985 0552 26-17, Pungmu-Dong Gimpo City, Kyunggi-Do 415-070 Republic of Korea CCI Japan Telephone: 81 726 41 7197 Fax: 81 726 41 7198 4-15-20 Shukunosho Ibaraki-City, Osaka 567-0051 Japan CCI Sweden (BTG Valves) Telephone: 46 533 689 600 Fax: 46 533 689 601 Box 603 SE-661 29 Säffle Sweden

CCI Austria (Spectris Components GmbH) Telephone: 43 1 869 27 40 Fax: 43 1 865 36 03 Lembockgasse 63, 1230 Wien AT-1233 Vienna Austria CCI Italy (STI) Telephone: 39 035 29282 Fax: 39 035 2928247 Via G. Pascoli 10 A-B 24020 Gorle, Bergamo Italy

Contact us at: [email protected] Visit us online at: www.ccivalve.com DRAG is a registered trademark of CCI. ©2003 CCI 316 01/03 7K