ASME Globe Valve
What's ASME Globe Valve?
Globe valves are linear motion closing-down valves used to start, stop or regulate the flow using a closure member referred as a disc. The seat of a globe valve is in the middle of and parallel to the pipe, and the opening in the seat is closed off with a disc or plug.The globe valve disc can completely close the flow path or can be removed entirely. The seat opening changes proportionately with the travel of the disc which is ideal for duties involving flow regulation. Globe valves are most suitable and widely used to control or stop the flow of liquid or gas through a pipe for throttling and controlling fluid flow and are generally employed in small size piping.
ASME Globe valve is one of the most popular design of globe valves,for US and API system.the inside diameter,materials,the face to face,wall thickness,pressure temperature,are are defined by ASME B16.34.
In addition,depending on the design of the seat and disc, the seating load of ASME globe valves can be positively controlled by a screwed stem. The sealing capacity of the ASME globe valve is very high. They can be used for on-off duty.Because of the short travel distance of the disc between the open and closed positions, ASME globe valves are ideal if the valve has to be opened and closed frequently. Thus, globe valves can be used for a wide range of duties.
the ASME Globe valves can be used for throttling purposes as well.Many single-seated valve bodies use cage or retainer-style construction to retain the seat-ring, provide valve plug guiding, and provide a means for establishing particular valve flow characteristics. it can also be easily modified by change of trim parts to change the flow characteristic or provide reduced-capacity flow, noise attenuation, or reduction or elimination of cavitation.
ASME Globe Valve Body Patterns,there are three primary body patterns or designs for Globe valves, namely:
- 1).Standard Pattern (also known as Tee Pattern or T – Pattern or Z – Pattern)
- 2).Angle Pattern
- 3).Oblique Pattern (also known as Wye Pattern or Y – Pattern)
Working Principle of ASME Globe Valve
A globe valve is comprised of a movable disc and a stationary ring seat in a spherical body. The seat of a globe valve is in the middle of and parallel to the pipe, and the opening in the seat is closed off with the disc. when the handwheel is rotated manually or by an actuator, the disc movement is controlled (lowered or raised) by means of the valve stem. When the globe valve disc seats over the seat ring, the flow is completely stopped.
Main feature of ASME Globe valve
- 1).Good sealing capabilities
- 2).Short travel distance of the disc(stroke) between the open and closed positions,ASME globe valves are ideal if the valve has to be opened and closed frequently;
- 3).The ASME globe valve can be used as a stop-check valve by modifying the design slightly.
- 4).There is wide range of capabilities as available in tee, Wye, and angle body styles.
- 5).Easy Machining and resurfacing of the seats,for various purposes.
- 6).Moderate to good throttling capability,by modifying the structure of seat and disc.
- 7).Bellows seal is available on request.
Technical specifications of ASME globe valves
|Design and Manufacture||BS1873/ASME B16.34|
|Face to face||ANSI B16.10|
|Flange dimension||AMSE B16.5|
|Butt weld dimension||ASME B16.25|
|Pressure-temperature Ratings||ASME B16.34|
|Test and inspection||API598|
|Bdoy||Carbon steel,Stainless steel,Alloy steel|
|Seat||stainless steel,alloy steel,Stellite coating.|
|Operation||handwheel,manual gear,electric actuator,pneumatic actuator|
|Pattern of body||Standard pattern(T-pattern or Z-type),Angle pattern,Y pattern|
Standard Trim Material to API 600
|Trim Code||Seat Ring Surface
Part No. 2
|Wedge Surface Part No. 3||Stem
Part No. 9
|13||Alloy 20||Alloy 20||Alloy 20||Alloy 20|
Standard Material Specifications
|Parts Name||Carbon Steel to ASTM||Alloy Steel to ASTM||Stainless Steel to ASTM|
|1||Body||A216 WCB||A352 LCB||A217 WC1||A217 WC6||A217 WC9||A217 C5||A351 CF8||A351 CF8M||A351 CF3||A351 CF3M|
|9||Bonnet||A216 WCB||A352 LCB||A217 WC1||A217 WC6||A217 WC9||A217 C5||A351 CF8||A351 CF8M||A351 CF3||A351 CF3M|
|6||Bolt||A193 B7||A320 L7||A193 B7||A193 B16||A193 B16||A193 B16||A 193 B8||A 193 B8||A 193 B8||A 193 B8|
|5||Nut||A194 2H||A194 2H||A194 2H||A194 4||A194 4||A194 4||A194 8||A194 8||A194 8||A194 8|
|11||Gland||A182 F6a||A182 F6a||A182 F6a||A182 F6a||A182 F6a||A182 F6a||304||316||304L||316L|
|12||Gland Flange||A216 WCB||A352 LCB||A217 WC1||A217 WC6||A217 WC9||A217 C5||A351 CF8||A351 CF8M||A351 CF3||A351 CF3M|
|3||Disc||A216 WCB||A352 LCB||A217 WC1||A217 WC6||A217 WC9||A217 C5||A351 CF8||A351 CF8M||A351 CF3||A351 CF3M|
|7||Gasket||SS Spiral Wound W/graphite, or SS Spiral Wound W/PTFE, or Reinforced PTFE|
|10||Packing||Braided graphite, or Die-formed graphite ring or PTFE|
|13||Stem Nut||Copper alloy or A439 D2|
|14||Hand Wheel||Ductile Iron or Carbon Steel|
Application of ASME Globe valves
ASME Globe Valve is widely used in a wide range of services; both low pressure and high pressure fluid services. The typical applications of globe valves are:
- 1).Designed for frequent on-off pipeline,or throttling the liquid and gaseous medium
- 2).Fluids:Water, steam, air, crude petroleum and petroleum products, natural gas, gas condensate, technological solutions, oxygen, liquid and non-aggressive gases
- 3).Cooling water systems requiring flow regulation.
- 4).Fuel oil system requiring leak-tightness.
- 5).Control valve bypass systems.
- 6).High-point vents and low-point drains.
- 7).Oil and Gas, Feedwater, chemical feed, Refinery, condenser air extraction, and extraction drain systems.
- 8).Boiler vents and drains, Steam services, main steam vents and drains, and heater drains.
- 9).Turbine seals and drains.