What is a Globe Control Valve?
A globe flow control valve is a common type of pressure control valve that is primarily responsible for the regulation of flow by linear movement of its moveable plunger. These control valves are named after their “spherical body shape” which further constitutes two halves. The one half of the spherical body has a seat that contains either a threaded or plain groove for plug or disc adjustment. The other half of the body contains a threaded closure known as Plug or Disc which can be screwed in the seat either by manual force or electric force. The extent to which the plug is screwed in the seat directly indicates the extent of flow regulation here.
In comparison to the gate valves which either completely allow or completely stop the fluid flow, the globe flow control valve has enabled the user to obtain customized fluid flow. The sealing action between plug and seat offers complete control on flow regulation while the small stem of globe flow control valves saves plug and seat from wear and tear. Moreover, the maintenance cost of these valves is significantly low compared to their market competitors.
The Working Principle of Globe Flow Control Valves
Pressure control valves have multiple applications in industry and the widely used type of it is Globe control valves. The globe control valves are principally manufactured to control and regulate the pressure flow of materials like steam, water, gas, etc in the industry. The basic components of the globe control valve assembly include a central body that holds the internal components, a disc or plug which is moved via the help of a stem. The below part of the body makes the seat surface which has wither smooth or screwed opening for disc fitting. To put the control valve in action, force is provided either manually or by using actuators.
After installation, when force is provided by actuators, the valve stem starts to move in a downward direction horizontally towards the fixed seat. This horizontally adjusted disc is perpendicular to the flow pathway and less leakage is observed. If the disc or plug is completely in contact with the seat surface, the material flow is stopped and when the disc is fully raised the material flow at its maximum speed. Modern electric actuated globe valves and pneumatic actuated control vales can provide customize the flow of the materials and the flow rate is in direct relation with the vertical traveled length of the stem.
Other arrangements of globe valves rather than horizontal direction are observed in different variants and models. If the disc closure system is arranged in the same direction of fluid flow, the K.E of fluid will assist the closure, that’s why a high-speed closure system is required in such control valves. But for control valves in which the valve closure system in opposite direction to the fluid flow, there is significant chances of leakage as fluid flow obstructs the closing, that’s why tightly sealed valve closure is required.
THINKTANK and Fischer Globe Control Valve Comparison
The FISHER brand is a big name in the mechanical field due to its standard mechanical products. The FISHER globe control valve is demanded all over the world to utilize in industrial products. But the cost of the FISHER Globe control valves is very high and small industrial setups find it difficult to afford their installation. THINKTANK globe control valves can be the best alternative to FISHER globe control valves due to their excellent features, high-class working and very low purchasing and maintenance cost.
THINKTANK offers a wide range of globe control valve in different dimensions so can be utilized for pressure control in small-scale, medium-scale and large-scale setups. THINKTANK follows the same standard protocol during manufacturing of these globe control valves which are followed by FISHER company.
As THINKTANK aims for high-quality products to compete with their competitors like FISHER, FLOWSERVE, SAMSON, no compromise is made on the selection of manufacturing materials. The body material of high-quality A216WCB, WCC, A352LCB, CF8M, CF8, CF3M, etc., is used to manufacture THINKTANK globe control valves to give customers the same working experience as that of FISHER glove control valves.
When it comes to pricing cost, THINKTANK is again taking the lead on FISHER globe control valves. The market price of FISHER globe control valves is almost 5~10 times higher as compared to THINKTANK control valves.
So, in conclusion, we can say that THINKTANK is doing a lot better in competition with FISHER globe control valves when it comes to dimensions, elegant design, working and price. You can get almost the same working experience at almost 5 times less cost as compared to FISHER company products. As THINKTANK always values its customers, different maintenance services, as well as customization services, are provided by the THINKTANK to customers all around the world. For further information about our products and services, do visit our official website cncontrolvalve.com or you can contact our HR department via online chat service or mail.
Globe Control Valve Assembly
The THINKTANK produces different variants of Globe flow control valves according to different industries’ needs and utility. In the following, we are going to discuss the general assembly line of a globe control valve.
Valve Closure or Plug design
The valve closure is attached with one part of the spherical body via stem and regulates the pressure-flow when screwed in the seat. Different designs of Valve closure are used in different variants to serve different purposes.
- The earliest model of globe valves had ball shaped metallic disc which fitted in the seat groove. These globe control valves are used for simple functioning like Open or stop flow.
- Globe control valves with composition disk contain a ring-shaped non-metallic disc that fits in the seat. These discs create a tight seal with a seat and are preferred to use in controlling the steam or hot water flow in the industry.
- The best type of valve closure is the plug type which enables to provide pressure controlling as well as pressure throttling ability to its user. The long pointed metallic plug got fixed in a deep groove in the seat and makes maximum contact with the seat surface. Moreover, the construction and replacement of these plugs and seats are easy and cheap.
In globe control valves manufactured by THINKTANK, the stem is attached with a spherical body and acts as a connector between plug and globe valve. In different variants, different material stems are utilized according to utility, yet a stem with high tensile strength material is preferred as it can endure high compressional force applied by the actuator. The plug is either the integral part or mounted on the stem and moves in response to the applied actuation force. In the case of a fixed plug, the rotatable stem is utilized so that it can provide free axial movement to the plug.
The seat is the fixed part of the surface which provides a surface for adjustment of a plug to create seal tight environment. In globe valves, the seat contains threads for disc adjustment to control the flow while in automated globe valves, the surface is smooth and the inside of the cavity is covered with PTFE or Graphite gasket. These gasket not only save the seat from wear and tear but also create airtight sealing environment results in maximum efficiency of organizing the fluid flow.
Bonnet is an important part of globe control valves which provide leakage-proof clave closure to a user. The threaded stem goes into the bonnet to adjust in seat hole with matching threads. Different mechanisms for bonnet assembly are applied in different models like bolts, welding, union, pressure-seal method or flanges, etc. THINKTANK-made globe flow control valves utilize bolts for attachment of bonnet with remaining assembly. This bolt attachment enables the globe flow control valves to operate at very high pressure in the industry. Packing material is also introduced there to produce a seal between the bonnet and stem of the globe flow control valve.
Actuator and their types
The earlier models of globe control valves are manually operated which contains handle or rotatory assembly to operate manually. The actuation force provided by the actuator is then transferred to the stem which moves the disc or plugs in a downward direction towards the seat for valve closure and vice versa. The modern units contain different actuation methods, the most important of them are Pneumatic actuators and Electric actuators respectively.
Pneumatic Actuated Globe Valves
The Pneumatic globe control valves manufactured made by THINKTANK is highly efficient and can be used for multiple purposes in different industries. THINKTANK pneumatic globe control valve is loaded with a powerful pneumatic actuator with multiple springs. These springs allow the fluid flow of very high pressure by putting a very small actuation force.
These pneumatic actuated globe valves used compressed air to mobilize the piston and springs to propel the piston in a backward direction when air allowed to release. The more powerful the actuator in pneumatic actuated globe valves, the more torque will be generated for the functioning of the valve.
Another important aspect of the pneumatic actuated globe valve is the “fail-safe position”. In case of any emergency or mechanical error, if the air supply is lost, the pneumatic actuated globe valve will immediately reach this position by using the tensile force of springs.
Electric Actuated Globe Valves
THINKTANK also manufactures the electric actuated globe valves to perform continuous action by the input signal. These electrically actuated globe valves are mostly utilized in industrial instruments which don’t have sufficient airflow.
Variation in Flow Directions at Different Temperatures
In industry, the temperature of different appliances is different according to their application. Flow directions through Globe valves are variate according to variations in temperature.
- If globe valves are intended to be utilized for low-temperature processes, they are installed in such a way that fluid pressure remains under the disk so the stem packing remains intact and maximum efficiency obtained.
- If globe valves have to be utilized in high-temperature operations, they are installed in such a way that fluid pressure remains above the disk. Failure to do so will result in stem contraction upon cooling due to which the disk will lift off and can’t able to fit in the seat properly.
Advantages of THINKTANK Globe Vales Usage
- Excellent flow controlling and throttling ability.
- Better shutoff ability.
- Simple working, easy handling, and manufacturing.
- Low maintenance cost and ease of seat, disc replacement.
- Available in Y, T, Z, and Angle designs and users can select according to their utility.
- The inner parts are replaceable, all the control valves can maintenance on the site.
Application Fields of THINKTANK Manufactured Globe Valves
- For regulation of fluid flow in industrial cooling systems.
- For maintenance of air pressure in fuel oil system where chances of explosion exist.
- For steam pressure regulation in the industrial boiler system.
- For regulation of the flow of materials in the chemical feed of feedwater system.