difference between gate valve and globe valve?

Answer 1

*A gate valve has a wedge of material which cuts across the flow area and seats around the circumference (or near the circumference) of the pipe.

A globe valve diverts the flow at right angles (or sometimes 45 deg to allow for external shaft drive) through a circular opening and the flow is checked or controlled by a circular disc which moves towards and ultimately seats on the bevelled edges of the circular opening. (for diagram see http://www.goddardvalve.com/270.htm... ) You are right it is different from a ball valve.
*Globe valves have been around for a long time, being one of the earliest types of valves. They have been used consistently in those services for which globe valves are ideally suited. The only changes over the years have been evolutions in materials and designs that have kept pace with changing conditions of service.For a better understanding of the functions of globe valves it is necessary to highlight one essential difference between globe and gate valves.

Gate valves are designed to completely open the line to flow, or to completely stop the flow. They are therefore, used wide open or fully closed, and are not intended for throttling service.

As opposed to a gate valve, a globe valve provides an additional function - it can be used wide open, fully closed, or with the disk in an intermediate position for regulating the flow. The character of the fluid and the degree of control desired determine the particular design of globe valve that should be used.

The predominant usage of globe valves is found in the three, appreciably different, basic types as shown above (ball-type disk,(composition disk), and (plug type disk). There are some modifications and variations of these disk and seat constructions, but they do not affect the fundamental differences or the recommended usages of the three basic types.
*Gate valves are primarily for open and closed service, and are not particularly adapted for intermediate flow regulation or throttling service. Due to their low head loss, which is only slightly greater than the equivalent length of pipe, they are particularly adapted for those services for isolation of equipment, where for long periods of time they will remain in the open or closed position, and offer little or no obstruction to the flow of fluid in the pipe line.
*Gate valves cover a wide range of sizes in common American practice - from 3/8 to 108 in., although in later years the 84 to 108 in. sizes have been supplemented by the butterfly valves, usually due to the space limitations under which they are installed.

Gate vales have been used successfully in temperature ranges of minus 300°F to 1800°F, and at pressures of from a few ounces of gas to thousands of pounds per square inch. Naturally the wide range of pressures and temperatures under which these valves are utilized necessitates a very wide range of materials of construction. Materials that are suitable at minus 300°F might not be suitable at 1800°F. At the present time gate valves are being manufactured in brass and bronze, several grades of gray iron, the newer ductile iron and the whole gamut of steel types, together with numerous special alloys for corrosion services.
*As per British standards, Landing valves ( Hose valves) should be gate valve for Dry risers and globe type for wet risers.
*In a chemical plant, simple or cascade loop control valve system are having globe valve in their bypass to control the flow in case of failure of control valve so that the continuity of the plant can be maintained.
*For low temperature service and hazardous service bellows seal globe valves are preferred.

Answer 2

Gate Valve Vs Globe Valve

Answer 3

Globe Valve Vs Gate Valve

Answer 4

A gate valve is normally used when the requirement is for on/off flow. The characteristic is such that most of the restriction to flow happens in the last 10 to 20% of valve travel.

A globe valve is good for regulating flow - so its not either on or off, but there is the whole way in between. If you have a control valve linked to the plant control system, there would normally also be a manual bypass (so you could isolate the control valve but still use the plant). This bypass is normally a globe valve because they can still be used to control the flow.

Answer 5

A gate valve should always be either fully open or fully closed. The main difference is in the form of the inner elements and the form of the flow inside the valves. In addition, the gate valve may have a rising or non rising stem while the globe valve is typically a rising stem design. You can buy globe valves online from www.kushasteels.com.au

Answer 6

Well, we're all around it. I like the answer the gate valve is like a garage door. That is about right. A globe valve the flow through the valve is forced through two 90 degree turns and the valve shuts off like a lid coming down in between the two turns. Not sure why the fire requirements are that way.

Answer 7

This Site Might Help You.

RE:
difference between gate valve and globe valve?

Answer 8

A gate valve is basiclly like a door riding in a groove , like a shower door. used to open or close water and sometime air lines.
A globe valve uses a shaped plug to control the volume of water or air through a hole in the valve body. This could also be called a metering valve.

Answer 9

A gate valve is typically on or off; a shutoff type valve. They can be operated manually or electrically with an electric motor.

Globe valves are used to meter the flow through the process. They typically have a closed loop control via downstream pressure or flow demand to control the electric or stepper motor to position the metering element.

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Answer 10

Supplement to clear -up a couple notations.
A ball valve is not a globe valve. It is a form of plug valve where the plug is round instead of conical. The plug valve is turned to activate, the gare and globe are raised or lowered to activate.

Answer 11

the gate valve is a peice of metal move up und down to close in and controll the flow, it is designated to hold pressure and control the flow too.
the globe valve which called some times the ball valve is a ball sit in an orifice which made up from tangestin carbide, this ball has a bore in it which used to close in high pressure system but it is very difficult to be used to control the flow.
the ball valve as same as the the water tap which has a lever which turn 90 deg only for full open and full close.