zecovalve

Globe valve, also known as stop valve, belongs to the forced sealing valve. So when the valve is closed, pressure must be applied to the disc so that the sealing surface does not to leak. When the medium enters the valve from the bottom of the disc, the resistance to be overcome by the operating force is the friction between the valve rod and the packing and the thrust generated by the pressure of the medium. The force to close the valve is greater than the force to open the valve, so the diameter of the valve rod is larger, otherwise the valve rod will be bent. According to the connection mode, it can be divided into three types: flange connection, screw connection and welding connection. After the appearance of the self sealing valve, the flow direction of the medium of the globe valve is changed from the top of the valve disc to the valve chamber. Under the medium pressure, the force to close the valve is small, while the force to open the valve is large, and the diameter of the valve rod can be correspondingly reduced. At the same time, under the action of medium, this type of valve is also strict. "Standardization, serialization and universalization" of the value in China stipulates that the flow direction of globe valve shall be from top to bottom. When the globe valve is opened, the opening height of the disc is 25% - 30% of the nominal diameter. When the flow has reached the maximum, it means that the valve has reached the full open position. Therefore, the full open position of the globe valve shall be determined by the stroke of the disc.

The opening and closing parts of the globe valve are plug-shaped disc, the sealing surface is flat or conical, and the disc moves in a straight line along the centerline of the fluid. The movement form of the valve rod includes the lifting rod type (the valve rod is lifted and the handwheel is not lifted) and the lifting rotating rod type (the handwheel is rotated and lifted together with the valve rod, and the nut is set on the valve body). The globe valve is only suitable for full open and full close, and it is not allowed to regulate and throttle.

Globe valve belongs to the forced sealing valve. So when the valve is closed, pressure must be applied to the disc so that the sealing surface does not leak. When the medium enters the valve 6 from the bottom of the disc, the resistance to be overcome by the operating force is the friction between the valve rod and the packing and the thrust generated by the pressure of the medium. The force to close the valve is greater than the force to open the valve, so the diameter of the valve rod is larger, otherwise, the valve rod will be bent. In recent years, since the appearance of the self sealing valve, the flow direction of the medium of the globe valve is changed from the top of the valve disc to the valve chamber. Under the medium pressure, the force to close the valve is small, while the force to open the valve is large, and the diameter of the valve rod can be correspondingly reduced. When the globe valve is opened, the opening height of the disc is 25% - 30% of the nominal diameter. When the flow has reached the maximum, it means that the valve has reached the full open position. Therefore, the full open position of the globe valve shall be determined by the stroke of the disc.

The advantages of globe valve are as follows:

1. It is simple in structure and it is easy to manufacture and maintain.

2. Small working stroke, short opening and closing time.

3. Good sealing performance, small friction between sealing surfaces and long service life.

The disadvantages of globe valve are as follows:

1. The fluid resistance is large, and the force required for opening and closing is large.

2. It is not suitable for medium with particles, high viscosity or coking medium

3. Poor regulation performance.

Types of globe valve:

According to the position of stem thread, the type of globe valve is divided into external thread type and internal thread type. According to the flow direction of the medium, there are straight-through type, direct current type, and angle type. According to the sealing form, the globe valve is divided into packing seal globe valve and bellows seal globe valve. 

ZECO valve supplies a wide range of globe valves. Our popular products include a105 globe valve, flange globe valve, wcb globe valve, etc. If you want to know globe valve price, please feel free to contact us.

Structure of globe valve body:

The structure of globe valve body includes straight-through type, straight flow type and right angle type. Straight through type is the most common structure, but its fluid resistance is the largest. The straight flow type has less resistance and is mostly used for fluid with solid particles or high viscosity. The right-angle valve body is mostly forged, which is suitable for the globe valve with small diameter and high pressure.

For the installation and maintenance of globe valve, the following items shall be noted:

1. The globe valve of hand wheel and handle operated can be installed at any position of the pipeline.

2. Hand wheel, handle and transmission mechanism are not allowed to be used for lifting.

3. The flow direction of the medium shall be consistent with the arrow direction shown in the valve body.

The globe valve has the following advantages:

1. In the process of opening and closing, the friction of the sealing surface is smaller than that of the gate valve, which is wear-resistant.

2. The opening height is small.

3. Generally, there is only one sealing surface, with good manufacturing process and easy maintenance.

There are many kinds of globe valves, which can be divided according to the position of the thread on the stem:

1. Upper thread stem globe valve

The thread of the globe valve stem is on the outside of the valve body. Its advantage is that the valve stem is not eroded by the medium, and it is easy to lubricate. This structure is widely used.

2. Lower thread stem globe valve

The thread of the globe valve stem is in the valve body. The stem thread of this structure is in direct contact with the medium. It can be easily eroded and cannot be lubricated. This kind of structure is used in small caliber and low-temperature areas.

According to the channel direction of the globe valve, it can be divided into: straight through globe valve, angle globe valve and three-way globe valve. The latter two kinds of globe valves are usually used to change the flow direction of the medium and distribute the medium.

ZECO is a professional Valve factory, we provide trunnion mounted ball valve china, international standard valve and etc. Contact us to know globe valve characteristics or more.