Valve Division

Turbine bypass valves play a very major role in Power Plant applications. Within a short period of twenty four hours, a power plant may be required to operate at minimum load, increase to maximum capacity for major part of the day, immediately lower back to minimum load and then back to maximum capacity. Bypass System permit unit start up and shutdown in a lifesaving manner for critical heavy components in boiler and turbines. Jet Flow Bypass valves are supplied with hydraulic, electric or pneumatic actuators as per the process requirements alongwith complete control systems as an option.

 

 

Functions:

 

• To perform quick and economic start up, including cold start, warm start and hot start in a lifesaving manner for critical heavy components in boiler and turbine.
• To operate with the boiler shutdown.
• To perform warm and hot startup in a short time after a trip i.e. brings the unit back to load
• To run the unit down to house load.
• To perform real “two-shift’ operation”.
• To avoid condensate losses to the atmosphere and reduce the start up noise to the ambient outside the plant.

 

Applications:

 

There are two different applications:
1) Bypass Systems which are occasionally in operation. Among these there are startup and shutdown conditions and emergency conditions, for example after turbine trip.
2) Bypass System which are often or permanently in operation, for example for process steam or heating application.

 

 

Actuators:

 

Bypass valves can be supplied with Pneumatic Piston & Cylinder, Electric or Hydraulic Actuators alongwith power pack and complete control system as per the requirements of the system.

 

Materials:

 

For most sizes, casting or forgings in Carbon and Alloy Steel can be supplied. For extremely large sizes, units are fabricated. Bypass Valves are normally supplied with butt weld ends. However, if required can be supplied with flanged ends.

 

 

Multi-Stage Multi-Path Pressure Reduction via Velocity Control trim technology:

 

• Jet Flow Jet Stack trim has stack of discs and each disc is tailor made for a particular flow path that has a variety of features:
• OurJet Stack trim technology uses a series of multi-stage multi-path disc stack for successful operation of our valves in severe service conditions.
  The passes through an extremely tortuous path at right angle turns thereby reducing the fluid velocity and therefore reduces the noise and eliminates erosion and vibration problems. The Jet Stack disc stack is tailor-made as per the requirement of our customers.
  The thickness of the wall of Jet Stack trim is such that it ensures maximum tortuous flow path. It ensures the fluid has a uniform velocity and as it passes through the disk it is streamlined.
• Its design ensures the flow to be distributed evenly throughout the disc. The open flow channel ensures even distribution.
• Irrespective of flow direction, multi channels are provided. Multi channels evenly distribute fluid around the plug for full stroke thereby ensuring complete control, reliability and stability.

 

 

Advantage of Jet Flow Turbine Bypass Valves with Jet Stack Velocity Control trim and laval jet nozzle -

 

• Series of pressure reducing stages are incorporated in the valve that can go as high as 60 for severe service let down applications. This ensures complete velocity control for the full load with noise levels reduced below 85 dBA.
• Complete tight shut off valve maintaining class V seat leakage.
• High rangeability of 50:1 as a standard is provided, however, higher turn down of 100: [can also be provided upon request.
• Minimum wall thicknesses of the body as per the design conditions to minimize thermal stress and shock.
• Complete trim assembly is easy to assemble and
• disassemble since no welded designs are incorporated.
• Extremely low maintenance cost with rapid trim
• change over from top.
• The trim has a very long life on account of extremely
• low velocities and with proper use of selected
• materials.
• Laval jet atomizing desuperheater incorporated in the valve ensures no impingement of the water on the downstream piping and thereby no need to install expensive thermal sleeves or liners.
• Substantial savings from the point of installation since the downstream straight length required is extremely short and therefore transition sockets and pipes can be installed very close to the valve.
• Extremely installation friendly. The valve can be installed in either vertical or horizontal direction.

High Pressure Control Valve is designed and developed for applications where the high pressure / drop liquid and high pressure / temperature gas/vapour to be handled. Our specially designed Velocity Control Trim, which is a multi turn / multi-stage velocity control trim, handles these  severe/critical applications  very effectively – eliminating cavitation & vibration, and reducing the noise to the acceptable levels.
Features:
Velocity Control Trim
ASME B16.34 design standard
Excellent flow control rangeability
Linear, equal % and modified linear inherent flow characteristics
Leakage rate up to Class VI (as per ANSI/FCI 70-2)
Quick Change Trim Design Option
End Connection Styles: Flanged Butt Weld Socket Weld Screwed.
Actuator Options:  Spring return diaphragm type as standard, other actuators viz. Electrical, Electro-hydraulic etc as options.
Stem  Packings-  PTFE for temperature up to 230 Deg. C Graphite for high temperature
Accessories options - Pneumatic positioners, Electro- Pneumatic positioners, Smart positioners, Solenoid valves, Limit Switches, Air Filter Regulators etc. are available.
Plug Options: Unbalanced Metal/Metal Unbalanced Soft seat Direction of Flow: Flowed over
Cv Values and Valve Dimensions - Each valve is designed separately based on the given process data, service conditions and pipe line size & schedule. Cv values and valve dimensions would depend on the required no. of turns/stages, flow characteristics & pressure rating, and decided upon case by case basis. Hence, Cv values are not given in this technical bulletin; they would be specified on the calculation sheet and technical specification sheet of each valve.

A Steam Conditioning Valve / Combined PRDS Valve is the combination of pressure reduction and temperature reduction of superheated steam to fit process needs, protect downstream equipment or allow the use of less expensive materials or schedules for downstream piping. This is done with a pressure reducing valve and a spray water addition section either as separate units or a single device. Pressure reduction is carried out with a pressure reducing trim within the valve body, usually multi stage pressure reduction. The pressure is controlled by an upstream or downstream pressure controller, signaling the valve to modulate to maintain the pressure at the required set point.Temperature is controlled by adding water to the steam in such away that it will get fully evaporated in the steam, termed as desuperheatmg.

These applications are normally considered to be some of the most severe services of any valves in a modem steam plant.

A Steam Conditioning Valve  Jet Flow steam conditioning valve with revolutionary multinozzle atomizer and feed forward design adds to our latest generation of quality valves. The equipment is utilised for simultaneous pressure and temperature reduction of steam. The cooling water is introduced in the highest turbulent zone of the steam. High steam velocity at this point, results in the highest coefficient of heat transfer between the steam and water. The feed forward design assures soft misty spray and instantaneous temperature control over the full range of steam flow.

• For high pressure let-down, pressure drop is taken across concentric flow cages rather than across seating surface, resulting in minimal seat wear.
• Pilot operated cage design to achieve extremely tight shut of (leakage classification ANSI# V)
• Balanced design with heavy duty pilot spring greatly improves throttling stability at high pet?P
• Larger outlet and outlet diffuser options give noise attenuation at optimum design conditions guaranteeing outlets sound pressure level to 85 dBA.
• Stellited trim increases its resistance to corrosion, erosion by abrasion, galling and sticking.

Steam Conditioning Valve Jet Flow steam conditioning valves are available in a variety of combinations. These valves are made as per tailor made requirements of customers. The valves are manufactured in angle, Z and globe forms.  Spray water entry is from the top through hollow stem as well as from the bottom, depending upon the process parameters.

Applications are but not limited to:

• Steam Conditioning Valves
• Reheater Valves
• Automatic Re-circulation Valves
• Superheater Spray Control Valves
• Boiler Feed Control Valves
• Start up Steam Vent Valves
• Spray Water Valves

Multi-Stage Multi-Path Pressure Reduction via Velocity Control trim technology:

• Jet Flow Jet Stack trim has stack of discs and each disc is tailor made for a particular flow path that has a variety of features:
• OurJet Stack trim technology uses a series of multi-stage multi-path disc stack for successful operation of our valves in severe service conditions.
  The fluid passes through an extremely tortuous path at right angle turns thereby reducing the fluid velocity and therefore reduces the noise and eliminates erosion and vibration problems. The Jet Stack disc stack is tailor-made as perthe requirement of our customers.
  The thickness of the wall of Jet Stack trim is such that it ensures maximum tortuous flow path. It ensures the fluid has a uniform velocity and as it passes through the disk it is streamlined.
• Its design ensures the flow to be distributed evenly throughout the disc. The open flow channel ensures even distribution.
• Irrespective of flow direction, multi channels are provided. Multi channels evenly distribute fluid around the plug for full stroke thereby ensuring complete control, reliability and stability.

Applications:

• Jet Stack trim has a wide range of applications that demand velocity control and massive pressure drops to be
• catered to across the valve.
• It assists in eliminating cavitation and erosion of the conventional type trim designs, reduces velocity, decreases noise and provides stable control over the entire ?ow range of the ?uid.

Advantage of Jet Flow Steam Conditioning Valvewith Jet Stack Velocity Control trim and laval jet nozzle -

• Series of pressure reducing stages are incorporated in the valve that can go as high as 60 for severe service let down applications. This ensures complete velocity control for the full load with noise levels reduced below 85 dBA.
• Complete tight shut off valve maintaining class V seat leakage.
• High rangeability of 50:1 as a standard is provided, however, higher turn down of 100: [can also be provided upon request.
• Minimum wall thicknesses of the body as per the design conditions to minimize thermal stress and shock.
• Double acting spring return pneumatically operated cylinder piston actuators are provided as a standard. Electric and Hydraulic actuators can also be provided as an option.
• Complete trim assembly is easy to assemble and
• disassemble since no welded designs are incorporated.
• Extremely low maintenance cost with rapid trim
• change over from top.
• The trim has a very long life on account of extremely
• low velocities and with proper use of selected
• materials.
• Laval jet atomizing desuperheater incorporated in the valve ensures no impingement of the water on the downstream piping and thereby no need to install expensive thermal sleeves or liners.
• Substantial savings from the point of installation since the downstream straight length required is extremely short and therefore transition sockets and pipes can be installed very close to the valve.
• Extremely installation friendly. The valve can be installed in either vertical or horizontal direction.
• Spray Water Control Valve -It is of extreme importance that steam temperatures are maintained in utility power plant to ensure safe, reliable and ef?cient operation of the equipment. Spray water control valves are the ultimate control elements for superheaters, reheaters, etc. A ?nely balanced steam temperature control valve will ensure trouble-free maintenance of the equipment for longer runs in a utility power plant.

Requirements -

• Gives the exact quantity of spray water as per the control demand for the entire operating range.
• Valve should be Class-V tight shut-off so that the downstream piping/ equipment  are not damaged.
• Should be suitable for higher pressure let down applications without internal damage of the trim.
• Reliable and consistent operation.

Jet Flow Safety Valve represent the most advance technology in value designed for use in intermediate power boiler and organic fluid vaporizer service. Built in conformance to section I of the ASME boiler and pressure vessel code, all capacities am certified by the national board of boiler and pressure vessel inspector at 5% over pressure.

Jet Flow Designed Safety Valve with Full Nozzle & hardened disc to minimize maintenance and increase seat life Open bonnet & Close bonnet both design have maximum set pressure 75 bar in Safety Valves.

Technical Details :

• Size Range - 15 mm TO 200 mm
• Moc - Cast steel,CF8,CF8M,GM
• End Connection - Screwed End, Flanged End, Butt weld
• Pressure Rating - 150 class, 300 class
• Trims - SS 304,SS 316

• Design  :
  
  • Angle Type(Lever operated / without lever)
  • Pop Type (Lever operated / without lever)
  • Open Discharge Type (Lever operated / without lever)
  • Angle type CP

• Design Standard - API 526 ,520 & IBR
• Testing Standard - API 527
• Flange drilling - ANSI B16.5
• Leakage test - API 527
• Suitable Application - Steam, Gas, Air, Water, Oil

While Enquiry Please Specify :

• Material of Construction.
• Set pressure in psig or Kg/cm2 (g).
• Maximum inlet temperature.
• Allowable over-pressure.
• Service-Specify either the media to be handled or the following physical properties or both.
• Liquids-Specific gravity (Water = 1)
• Gases-Specific gravity (Air=1)
• Vapors-Molecular weight (mixture of vapors. The average molecular weight)
• Back pressure, if any.
• Required capacity.
• Type of End-connections.
• Preferred inlet size.

Jet Flow fixed area nozzle desuperheaters are best suited for applications involving minimal load fluctuations. A fixed nozzle desuperheater utilizes high performance fixed geometry nozzles to reduce the steam temperature by directly injecting water inside the superheated steam flow. The water enters the main desuperheater body, passes through the spray nozzles and discharges into the steam line in the form of a fine mist.