Two shift operation power plants

Power stations that were originally designed for base load applications are now increasingly
being asked to operate on a two shift, stop/start regime; this is more commonly known in the
industry as dual shifting. The multiple start/stops that these stations are now experiencing are in
some instances causing an increase of operational issues due to the constantly changing process
parameters. For example dual shift stations will experience additional thermal stress in the
headers, drums, high temperature piping, valves plus the auxiliary equipment leading to
additional wear and tear of their systems and component parts. This is due to the more frequent
use of the plant at severe service conditions. The consequences of the change in plant operation
cannot be ignored. If the plant is not operated correctly, or more importantly...
(download the paper below)

Two shift operation power plants

Power stations that were originally designed for base load applications are now increasingly
being asked to operate on a two shift, stop/start regime; this is more commonly known in the
industry as dual shifting. The multiple start/stops that these stations are now experiencing are in
some instances causing an increase of operational issues due to the constantly changing process
parameters. For example dual shift stations will experience additional thermal stress in the
headers, drums, high temperature piping, valves plus the auxiliary equipment leading to
additional wear and tear of their systems and component parts. This is due to the more frequent
use of the plant at severe service conditions. The consequences of the change in plant operation
cannot be ignored. If the plant is not operated correctly, or more importantly...
(download the paper below)

Configuration

Valves with stuffing box or bellows sealed pressure seal bonnet or blank flange.

• DN 50-1000
• PN up to 40, DN 50-300
• PN up to 100, DN 50-300
• PN 160, DN 50-700
• PN 100-630 (PD 10-63), DN 10-50
• PN up to 100 (Class 800)

Body materials:

• Carbon steel: 1.0425, 1.0460, 1.5415
• Alloy steel: 1.4901, 1.4903, 1.6368, 1.7335, 1.7383,
• Stainless steel: 1.4571
• Stainless steel low temperature: 1.4308
• Other materials on request

Connections:

• Flanges
• Butt weld ends
• Socket weld ends ≤ DN 50
• ASME on request

Features

• "Split wedge" construction
• Rail guided discs
• Die-forged body and bonnet
• Non-turning, rising stem
• Spindelnut with bearing
• Easy assembly of an E-actuator
• Pressure sealed bonnet acc. VGB-guidelines

Design Highlights

• Main valve body is one-piece die-forged incorporating the bonnet flange and the guide for the shut-off device
  Die-forged parts, compared with cast steel parts are generally free from porosity and shrink holes. The special of the valve body minimizes the existance of welding seams.
• Valve body equipped with guiding system
  Compared to parallel slide valve an almost friction free stroke
• Hard faced seats (app. 35-37 HRC)
  Extremely resistant to wear
• Full bore, except DN 65/50 and DN 125/100
  No reduction in seat area
• Hammer head connection between wedge and stem
  The wedges are able to move parallel to the axis of the pipeline within the guiding groove. This protects the stem against bending moments
• Pressure sealing bonnet
  Best possible sealing function

Manufacturer

PERSTA is a market leader in the high performance forged steel isolating valves. Established manufacturer, part of the Siepmann Group with their own forging shop. Especially the high pressure globe and gate valves are a benchmark in the valve industry with a flexible production process.

• Globe valves
• Gate valves
• Check valves
• Bellow seal valves
• Special valves
• Valves for super critical boilers

Feed water control valves are one of the most important control components of the water-steam circuit. The valve controls the supply of feed water to the boiler. The valve’s requirements are high. The pressure drop across the valve should be minimized, but still give a l good control characteristic. A main feed water control valve is designed for the total flow of the steam generation at low differential pressures. The start-up valve however, is used for low flows and high pressures.

Advanced Valve Solutions also provides a special design feed water control valve which gives us the opportunity to combine the start-up and main feed water control function in one valve. A decisive cost benefit for our customers!

Configuration

• Main feedwater control (30-100%)
• Start-up feedwater control (0-30%)
• Combi feedwater control (0-100%)

Features

• High quality forged- or castings
• Z-type, angle or straight pattern
• BW / flange connection according DIN or ANSI
• + balanced plug / - balanced plug / pilot plug
• Custom control characteristic
• Singe- or multistage construction
• Seat: clamped
• Plug: parabolic, perforated cage, perforated plug, V-port
• DIN
• ANSI
• Pneumatic / electric

Benefits

• Multi stage cavitation free control
• Number of stages designed for particular application
• Superior rangeability
• Tight shut off
• Easy maintenance
• No separate start up valve needed

Manufacturer

HORA is a German manufacturer of high pressure steam and water control valves covering all control systems in modern power plants. Together with a very good R&D department we are continuously seeking for better solutions and controllability of the steam water cycle. Flexible and dedicated performance company, supplying all tailor-made products.

• Control valves
• Steam conditioning valves
• Feed water Control valves
• Water injection valves
• Desuperheater valves
• Turbine bypass valves
• Turbine shut-off valves
• Automatic recirculation valves (Pump protection)
• Valves for super critical boilers

The metal & rubber/elastomer special engineered expansion bellows made by MACOGA can be broadly applied in applications within (Petro-)Chemical, Power, Geothermal, Oil & Gas, Iron & Steel, Cement industries and many more.

• Standard and exotic materials
• Refractory linings
• Diameters up to DN8000.
• Circular shapes (axial, hinged, gimbals, lateral, pressure balanced, jacketed, etc.)
• Rectangular shapes (V - & U shaped)
• Single and multiple plies
• “Dog Bone” joints

Configuration

Valves with stuffing box or bellows sealed pressure seal bonnet or blank flange.

• DN 50-1000
• PN up to 40, DN 50-300
• PN up to 100, DN 50-300
• PN 160, DN 50-700
• PN 100-630 (PD 10-63), DN 10-50
• PN up to 100 (Class 800)

Body materials:

• Carbon steel: 1.0425, 1.0460, 1.5415
• Alloy steel: 1.4901, 1.4903, 1.6368, 1.7335, 1.7383,
• Stainless steel: 1.4571
• Stainless steel low temperature: 1.4308
• Other materials on request

Connections:

• Flanges
• Butt weld ends
• Socket weld ends ≤ DN 50
• ASME on request

Features

• "Split wedge" construction
• Rail guided discs
• Die-forged body and bonnet
• Non-turning, rising stem
• Spindelnut with bearing
• Easy assembly of an E-actuator
• Pressure sealed bonnet acc. VGB-guidelines

Design Highlights

• Main valve body is one-piece die-forged incorporating the bonnet flange and the guide for the shut-off device
  Die-forged parts, compared with cast steel parts are generally free from porosity and shrink holes. The special of the valve body minimizes the existance of welding seams.
• Valve body equipped with guiding system
  Compared to parallel slide valve an almost friction free stroke
• Hard faced seats (app. 35-37 HRC)
  Extremely resistant to wear
• Full bore, except DN 65/50 and DN 125/100
  No reduction in seat area
• Hammer head connection between wedge and stem
  The wedges are able to move parallel to the axis of the pipeline within the guiding groove. This protects the stem against bending moments
• Pressure sealing bonnet
  Best possible sealing function

Manufacturer

PERSTA is a market leader in the high performance forged steel isolating valves. Established manufacturer, part of the Siepmann Group with their own forging shop. Especially the high pressure globe and gate valves are a benchmark in the valve industry with a flexible production process.

• Globe valves
• Gate valves
• Check valves
• Bellow seal valves
• Special valves
• Valves for super critical boilers

Steam cooling is the opposite process of super heating and crucial in several processes. HORA manufactures a complete package of different types of desuperheaters, every type with its particular properties. HORA precisely determine the CFD (Computer Fluid Dynamics) analysis for your application providing the optimum, most cost-effective version. Various products are available are available for this purpose.

Configuration

Applicable for:

• Processsteam
• Intermittent cooling superheater
• Final cooling superheater
• Condensor protection
• Other cooling applications

Configurations:

• Multi stage desuperheater
• Venturi desuperheater
• Desuperheating with atomizing unit
• Static injection lance
• "Cooled desuperheater"

Features

• One piece, forged body (F1, F11, F22 and P91)
• Integrated injection valve
• Single- of multistage internal
• Cavitation free internal
• Due to control unit, avoid cavitation and always maintain an optimum pressure drop over the nozzle

Benefits

• Easy maintenance due to clamped internals
• No separate injection valve necessary
• Anti cavitation trim
• Seat located outside hot area
• No welding connections
• Optimal spray due to optimal pressure drop over injection nozzle
• Thermoshock free!

Manufacturer

HORA is a German manufacturer of high pressure steam and water control valves covering all control systems in modern power plants. Together with a very good R&D department we are continuously seeking for better solutions and controllability of the steam water cycle. Flexible and dedicated performance company, supplying all tailor-made products.

• Control valves
• Steam conditioning valves
• Feed water Control valves
• Water injection valves
• Desuperheater valves
• Turbine bypass valves
• Turbine shut-off valves
• Automatic recirculation valves (Pump protection)
• Valves for super critical boilers

Nil-Cor is the worlds largest supplier of High Technology industrial valves made from strong, light weight composite materials. The graphite and fiberglass reinforced thermoset and thermoplastic resins are resistant to acids, caustics, bleaches and more than one thousand other industrial and waste treatment chemicals, at half the cost of traditional alloy valves.

Configuration

Zirconia ceramic lined ball valves

• Range, 1" - 8"
• Body, Graphite fiber-reinforced Vinyl Ester or Epoxy
• Ball, Zirconia Ceramic Standard Port or V-Port for control
• Seats, Zirconia Ceramic or UHMWPE
• Stem, cast-C encapsulated with composite, or solid Hast-C

Butterfly valves

• Range, 2"- 42" Wafer and LUG
• Flange drilling, ANSI / DIN
• Types, Full Faced Wafer / Threaded LUG
• Body, Glass fiber-reinforced Vinyl Ester
• Liner, EPDM / Hypalon / UHMWPE
• Disc, EPDM/DI / Hypalon/DC / 316 SS
• Pneumatic / Electro-pneumatic / Manual

Ball Check Valves

• Range, 1"- 6" Flanged
• Flange drilling, ANSI / DIN
• Construction, One-piece
• Body, 300 Graphite/Vinyl ester, 310 Glass/Vinyl ester, 410 Glass/Polysulfone, 500XP Graphite/Epoxy, 610XP Glass/Epoxy
• Ball, PTFE / Polypropylene
• Seat, FKM Fluorelastomer

Swing Check Valves

• Range, 3" - 12"
• Flange driling, ANSI / DIN
• Construction, One-piece wafer style
• Body, 300 Graphite/Vinyl ester, 310 Glass/Vinyl ester, 500XP Graphite/Epoxy, 610XP Glass/Epoxy
• Flapper, 300 Graphite/Vinyl ester, 310 Glass/Vinyl ester, 500XP Graphite/Epoxy, 610XP Glass/Epoxy
• Seat, FKM Fluorelastomer

Benefits

• Corrosion Resistance
• Light Weight
• Strong and Durable
• Safe and Reliable

Manufacturer

Nil-Cor is a US based manufacturer and worlds-leader of reinforced composite Ball -, Check - and Butterfly valves. Designed acc. ASME Class 150Lbs B16.5 (DIN 2501/PN16) flange rating. Corrosion resistant to a large number of acids, caustics, bleaches, solvents and salts. Good substitutes to expensive and long lead exotic materials. Valves weight approximately 1/3 less then normal valves. Typical applications are cooling - and fire fighting (sea-)water and pure chemicals.

• Graphite - and Glass fiber reinforced Vinyl Ester and Epoxy
• Flanged and Threaded Ball valves
• Ball- & Swing type Check valves
• Wafer/Lug type Butterfly valves with elastomer liners or in full composite
• Ceramic’s for abrasive services

The metal & rubber/elastomer special engineered expansion bellows made by MACOGA can be broadly applied in applications within (Petro-)Chemical, Power, Geothermal, Oil & Gas, Iron & Steel, Cement industries and many more.

• Standard and exotic materials
• Refractory linings
• Diameters up to DN8000.
• Circular shapes (axial, hinged, gimbals, lateral, pressure balanced, jacketed, etc.)
• Rectangular shapes (V - & U shaped)
• Single and multiple plies
• “Dog Bone” joints