095-369-0964

Bangkok

info@radiusglobal.co.th

fitting stainless line logo.webp

บทความ เกจวัดแรงดัน

Selecting the right control valve in your processing software 

The control valve plays a considerable role in establishing and sustaining an efficient course of. When deciding on among the many obtainable choices, make positive to consider how the control valve’s options match the application’s fluid requirements when it comes to versatility, steady circulate management, ability to deal with a variety of flows and connectivity for distant monitoring. Also search for traits that make it easier to maintain. Of the out there choices, rotary valves and linear angle valves offer widespread applicability.
Process control valve fundamentals
Control valves alter fluid circulate by various the size of the move passage as directed by a sign from a controller. This enables the direct management of flow price and the consequential control of key course of parameters, including stress, temperature and liquid degree.
Several major forms of management valves are available; every has professionals and cons and could additionally be most applicable for various functions. Finding the valve that works best for a specific application is a problem. Key issues relating to technical specification embody the extent of control supplied, decision achieved and the valve’s supply time. Maintenance and longevity also wants to be considered. Several components come into play during choice, including the necessity for application-specific information and expertise, economic restrictions, plant outage schedules and maintenance plans over the life of the valve.
Options obtainable
Linear globe valves are used for their versatility to manage flow over a variety, capacity to mitigate noise and since they offer simpler entry to valve internals during maintenance. They usually include a disk or cylindrical plug factor with a stationary ring seat in a usually spherical body. Globe valves embody stem-guided, cage-guided and top- and bottom-guided varieties. Stem- and top/bottom-guided valves are higher suited for common industrial and less-aggressive applications. Cage-guided valves are typically more expensive, but carry out in a broader scope of purposes and have more flexibility to include noise or cavitation mitigating features. All varieties could also be managed by electrical, pneumatic, manual or hydraulic means of actuation.
Linear angle valves are just like globe-style valves, however are better suited to essentially the most extreme applications with large flow rates, noise and flashing, for the reason that mitigating technology may be more efficiently sized and integrated into the plant system. Stem-guided and cage-guided choices are supplied and actuation is typically pneumatic or hydraulic as a outcome of high inside forces and rapid response needed in these purposes.
A linear three-way management valve has one inlet and two shops or vice versa and is used in industrial purposes. This permits mixing of liquids from two pipes into one pipe, or separating water from one pipe into two pipes. Typical applications embrace air-handling units, water chillers, boilers and fan coils. This possibility is often supplied in stem-guided and cage-guided choices. It is usually not used for essentially the most severe functions, however somewhat to manage the amount of flow or strain in a single section of the piping system with respect to a different.
Finally, rotary valves use the rotation of a passage or passages in a transverse plug to control the move of liquid or fuel. Rotary valves have a broad range of applicability, depending on the technology included in the internals. Globe and even angle valves have a comparatively torturous move path, which requires extra strain drop to achieve a given circulate, all other parameters being equal. A rotary valve can offer an inline, much less torturous path, whereas still providing related move control, rangeability and resilience in severe-system situations. Its structure provides inherent benefit in conditions the place the working fluid incorporates solids and cleanliness cannot be maintained. These circumstances would have a extreme impression on globe or angle valve performance.
Table 1 offers a common overview of the typical functions for which every management valve sort is most suited. Rotary valves provide by far essentially the most widespread applicability; linear angle valves are also appropriate for a broad range of purposes.
Table 1. General overview of the standard purposes for which each management valve kind is most suited
Other components affecting management valve choice
Industry and nation requirements, including American Society of Mechanical Engineers (ASME), Canadian Registration Number (CRN), Pressure Equipment Directive (PED) and American Petroleum Institute (API), amongst others, can affect the suitability of certain valve selections. In addition, number of the management valve for an application is affected by varying buyer expectations — finish users, engineering-procurement-construction (EPC) contractors and installation contractors have varying priorities in choice standards. Of these factors of view, the most important is the top user, who wants a management valve that gives the required control with the highest ease of use and maintenance over the valve’s life.
Features to look for in a management valve
During the choice course of, look for and consider how the choices into account meet these key features:
Versatility and ruggedness — Can the valve handle the full breadth of circumstances between the minimal and maximum specified conditions? Is it sturdy sufficient to resist upset conditions? Does it offer lengthy service life with out maintenance?
Works equally properly on clear, soiled, viscous, corrosive, abrasive, excessive pressure/temperature fluids liquids and gases — Standardization across the set up base helps with maintenance necessities and spare components stock. Adding filtering and cleansing of the working fluid in a system is nice apply, nevertheless it also will increase upkeep of those filters, which must be thought-about in system design.
Stable circulate control — Consistent management in all conditions is important. Inconsistency in management will lead to production downtime and loss of product.
Meets applicable linear, equal proportion or other management traits — Different process conditions require: completely different management characteristics. Know the characteristics required and evaluate and make sure the control valve meets them.
Rangeability — Make sure the valve can handle all move changes in the process.
Connectivity to a building/process management system — Remote monitoring and control is important to processing applications. Ensure the valve is compatible with the building/process administration system.
Features to ensure correct management valve upkeep
In addition to choosing valves that meet the criteria mentioned above, it is crucial the valves have features that guarantee correct upkeep. Here are the important thing features to look for:
Self-aligning seat ring for tight shutoff, no shimming or hardened materials
Access to the packing for inspection and adjustment
Splined or coupled shaft connections that enable ease of connect/disconnect from actuation
Blowout-proof shaft safety
Enclosed and self-purging actuator linkage
Ability to work on the valve with out having to remove the body from the system
The valve’s ability to maintain tight shutoff to reduce lack of working fluid when it is not needed downstream of the valve. Keep in mind that management valves are not isolation valves, so do not use them in lieu of correct isolation valves for plant security.
Rotary valve versatility
With a excessive vary ability of 100-to-1 turndown, and a small footprint, rotary management valves offer a larger circulate coefficient (Cv) than the standard globe type valve.
For example, Figure 1 exhibits a rotary valve utilized in a pulp and paper software that is designed to handle corrosive and erosive mediums and fiber on the same time. The geometry and operation of the stem-plug is such that it can operate under the harshest conditions, even shearing off material, while handling something flowing by way of it, from sludge-like material to sand and small debris. Maintaining efficiency in this utility with a globe valve will be far more troublesome, and may require additional maintenance or compromise in different efficiency parameters.
The valve in Figure 1 makes use of an environment friendly straight-through move design that allows for a a lot lower value per Cv than typical globe-style management valves. เกจวัดแรงดันน้ำ10บาร์ -shaft diameters machined of high-strength materials provide the torsional and flexural rigidity required underneath excessive working pressures.
A globe-style valve would require extra strain drop for a given move situation, driving the valve measurement larger, and the troublesome flow situations may cause quicker put on and tear of the internals.
Consider a rotary control valve
While many choices work for specific purposes, and globe or angle valves are extremely versatile, a rotary control valve can enhance on key software challenges that may in any other case lead to oversizing the valve and increased maintenance. This allows for decreased plant costs and reduced stocking requirements. (See Table 2 for benefits and advantages of rotary plug management valves.)
Share

บทความล่าสุด

เกจวัดแรงดัน มีประโยชน์

เกจวัดแรงดัน มีประโยชน์ ทำไมต้องใช้ในอุตสาหกรรม

ค้นพบประโยชน์ของเกจวัดแรงดัน และทำไมธุรกิจอุตสาหกรรมถึงห้ามพลาด เพิ่มความน่าเชื่อถือและความปลอดภัยให้กับระบบงานของคุณ.

Read More »