Production of cast iron globe valves

J41TCast iron globe valveProduct Description

The utility model enhances the sealing effect through a sealing buffer layer set under the valve seat, while reducing the wear of the valve disc and delaying its service life. The structure is relatively simple, easy to manufacture and maintain, the sealing surface is not easily worn or scratched, the sealing performance is good, the service life is long, the valve disc stroke is small when opening and closing, the opening and closing time is short, and the valve height is small. Widely used in industries such as water supply and drainage, gas, electricity, metallurgy, petroleum, chemical, textile, and urban construction, it is used for opening and closing pipelines for steam, water, and oil media.

J41TCast iron globe valveProduct Features

J41TCast iron globe valveIt is a commonly used shut-off valve, mainly used to control or cut off the medium in pipelines. It is generally not used to regulate flow. Globe valves are suitable for a wide range of pressure and temperature, but are generally used for medium and small diameter pipelines. Compared with gate valves, globe valves have a simpler structure, easier manufacturing and maintenance, less wear and tear on the sealing surface, better sealing performance, longer service life, smaller valve disc stroke during opening and closing, shorter opening and closing time, and smaller valve height. Widely used in industries such as water supply and drainage, gas, electricity, metallurgy, petroleum, chemical, textile, and urban construction, it is used for opening and closing pipelines for steam, water, and oil media.

J41TCast iron globe valveProduct advantages

1. Low flow resistance. The internal medium channel of the valve body is straight through, and the medium flows in a straight line with low flow resistance.

2. It is more effortless to open and close. Compared to globe valves, the direction of gate movement is perpendicular to the direction of medium flow, whether it is open or closed.

3. High height, long opening and closing time. The opening and closing stroke of the gate is relatively large, and the lowering is carried out through the screw.

4. Water hammer phenomenon is not easy to occur. The reason is that the shutdown time is long.

a kind ofCast iron globe valveThe valve is characterized in that it consists of a valve body and a valve cover installed on the valve body. The valve body is provided with an inlet chamber and an outlet chamber, and a valve seat is set at the connection between the inlet chamber and the outlet chamber. A sealing cushion layer is set under the valve seat. A sealing gasket is set between the valve body and the valve cover, and the valve body and the valve cover are fixedly connected by bolts. The valve cover is installed with the valve stem inserted into the valve cover, and a handwheel is installed on the upper end of the valve stem. The handwheel is fixedly connected to the valve stem through the bolt. The valve stem is sequentially fitted with a valve stem nut, a packing pressure plate, a packing pressure sleeve, a packing layer, and so on from bottom to top. A sealing ring is installed at the lower end of the valve stem, and a valve disc is fixedly connected to the valve stem through screws. A sealing ring is installed at the lower end of the valve disc, The lower surface of the valve disc is provided with an elastic sealing layer.

J41TCast iron globe valveperformance specifications

Main zero materials

This utility model provides aCast iron globe valveThe valve includes a valve body and a valve cover installed on the valve body. The valve body is equipped with an inlet chamber and an outlet chamber, and a valve seat is set at the connection between the inlet chamber and the outlet chamber. A sealing cushion layer is set under the valve seat, and a sealing gasket is set between the valve body and the valve cover. The valve body and the valve cover are fixedly connected by bolts, and a valve stem inserted into the valve cover is installed on the valve cover. The upper end of the valve stem is equipped with a handwheel, which is fixedly connected to the valve stem by bolts. The valve stem is sequentially fitted with a valve stem nut, a packing pressure plate, a packing pressure sleeve, a packing layer, and an upper sealing ring from bottom to top. The lower end of the valve stem is equipped with a valve disc, which is fixedly connected to the valve stem by screws. The lower end of the valve disc is equipped with a Sealing layer. This utility model enhances the sealing effect by setting a sealing buffer layer under the valve seat, while reducing the wear of the valve disc and delaying its service life.

The quality of the installation of the shut-off valve directly affects its use, so it must be carefully considered.

（1） Direction and position

Globe valves have directionality, and if installed upside down, it can affect their effectiveness and lifespan (such as throttle valves), or not work at all (such as pressure reducing valves), and even cause danger (such as check valves). General globe valves have directional markings on the valve body; If not, the correct identification should be based on the working principle of the shut-off valve.

The valve chamber of the globe valve is asymmetric on both sides, and the fluid should be allowed to pass through the valve port from bottom to top, so that the fluid resistance is small (determined by its shape), and opening is effortless (due to the upward pressure of the medium). After closing, the medium does not pressure the packing, making it easy to maintain. This is the reason why globe valves cannot be reversed. Other shut-off valves also have their own characteristics.

The installation position of the shut-off valve must be convenient for operation; Even if installation is temporarily difficult, consideration should be given to the work of the operators. The handwheel of the shut-off valve is aligned with the chest (usually 1.2 meters away from the operating floor), which saves effort in opening and closing the shut-off valve. The handwheel of the floor stop valve should be facing upwards and not tilted to avoid awkward operation. The shut-off valve of the wall mounted machine and equipment should also leave room for operators to stand. Avoid high-altitude operations, especially with acidic, alkaline, toxic media, etc., otherwise it is very unsafe.

（2） Construction work

Caution must be exercised during installation and construction to avoid hitting globe valves made of brittle materials.

Before installation, the globe valve should be inspected to verify its specifications and identify any damage, especially to the valve stem. We need to rotate it a few more times to see if it is skewed, because during transportation, the valve stem is most likely to be knocked off. Also, remove the debris inside the valve.

When lifting the globe valve, do not tie the rope to the handwheel or valve stem to avoid damaging these components. It should be tied to the flange.

The pipeline connected to the shut-off valve must be cleaned thoroughly. Compressed air can be used to blow away iron oxide chips, mud and sand, welding slag, and other debris. These debris not only easily scratch the sealing surface of the shut-off valve, but also large particles of debris (such as welding slag) can block the small shut-off valve, causing it to fail.

（3） Packing replacement

Inventory cut-off valves, some of the packing is no longer working properly, and some do not match the medium used, which requires replacement of the packing.

Valve manufacturers cannot consider using different media of thousands of types per unit. The packing box is always filled with ordinary packing, but when using it, the packing must be adapted to the medium.

When replacing the packing, press it in circle by circle. It is advisable to have a 45 degree joint for each circle, and the joints between circles should be staggered by 180 degrees. The height of the packing should consider the room for further compression of the gland, and now it is necessary to allow the lower part of the gland to press the packing chamber to an appropriate depth, which can generally be 10-20% of the total depth of the packing chamber.

For high demand globe valves, the joint angle is 30 degrees. The seams between the circles are staggered by 120 degrees.

In addition to the above-mentioned fillers, rubber O-rings (natural rubber resistant to weak alkali below 60 degrees Celsius, nitrile rubber resistant to oil below 80 degrees Celsius, fluororubber resistant to various corrosive media below 150 degrees Celsius), three piece stacked polytetrafluoroethylene rings (resistant to strong corrosive media below 200 degrees Celsius), nylon bowl shaped rings (resistant to ammonia and alkali below 120 degrees Celsius) and other shaped fillers can also be used according to specific situations. Wrap a layer of PTFE tape around the ordinary asbestos packing to improve the sealing effect and reduce the electrochemical corrosion of the valve stem.

When tightening the packing, the valve stem should be rotated simultaneously to maintain uniformity around and prevent it from becoming too tight. The tightening of the gland should be evenly applied and not tilted.

（4） Attention

1. The shut-off valve operated by handwheel and handle can be installed at any position in the pipeline.

2. Handwheels, handles, and dynamic mechanisms are not allowed for lifting purposes.

3. The flow direction of the medium should be consistent with the arrow direction shown on the valve body.

Ordering Notice:

1、 ① Product name and model ② Caliber ③ Is there any accessory for us to correctly select for you ④ Operating pressure ⑤ Temperature of the medium used.

2、 If the company's model has already been selected by the design unit, please order directly from our sales department according to the model.

3、 When the usage situation is very important or the environment is complex, please provide design drawings and detailed parameters as much as possible, and our valve company experts will review and control them for you. If you have any questions: Please: We will do our best to provide you with high-quality service. We provide comprehensive and professional "valve system solutions" and are also willing to help users solve problems encountered in production.