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Inside of a data center

What is the data center tier and classification system of the data center tier?

Data center tier
Data center tier refers to a standardized classification system that categorizes data centers based on their infrastructure design, reliability, redundancy, and availability. The tier system provides a way to evaluate and compare the resilience and performance capabilities of different data centers. The most commonly used tier system is the one developed by the Uptime Institute, a globally recognized organization for data center reliability and efficiency.

Classification system of data center tier by the Uptime Institute

The Uptime Institute’s tier classification system consists of four tiers:

1) Tier I: Tier I data centers have basic infrastructure components and provide a non-redundant environment for IT equipment. They have a single path for power and cooling, meaning they are susceptible to planned and unplanned downtime. They typically have an availability of approximately 99.671%, with a maximum of 28.8 hours of annual downtime.

2) Tier II: Tier II data centers offer some redundant components and infrastructure, providing improved reliability compared to Tier I. They have redundant power and cooling distribution paths but lack redundant components within those paths. They generally achieve an availability of around 99.741%, with a maximum of 22 hours of annual downtime.

3) Tier III: Tier III data centers have a concurrently maintainable design, ensuring that individual infrastructure components can be taken offline for maintenance or replacement without disrupting the IT operations. They feature multiple independent power and cooling distribution paths, allowing for maintenance without downtime. Tier III data centers aim for an availability of approximately 99.982%, resulting in a maximum of 1.6 hours of annual downtime.

4) Tier IV: Tier IV data centers provide the highest level of reliability and fault tolerance. They have redundant components, multiple independent distribution paths, and are designed to withstand individual equipment failures or planned maintenance without any disruption to IT operations. Tier IV data centers offer an availability of approximately 99.995%, with a maximum of 0.4 hours of annual downtime.

These tiers help data center owners, operators, and clients understand the level of infrastructure resilience and availability provided by a facility. Higher-tier data centers generally require more redundant systems and are designed to provide better uptime and fault tolerance. However, achieving higher tiers involves increased costs due to the additional infrastructure and redundancy requirements.

data center

What is data center PUE and the importance of PUE?

Power Usage Effectiveness (PUE)
Data center PUE stands for Power Usage Effectiveness. It is a metric used to assess the energy efficiency of a data center. PUE is calculated by dividing the total amount of power consumed by the data center (including IT equipment, cooling systems, lighting, etc.) by the power consumed solely by the IT equipment (servers, storage devices, networking equipment, etc.). The formula for calculating PUE is as follows:

PUE = Total Facility Power / IT Equipment Power

Ideally, a data center would aim for a PUE of 1, which would mean that all the power consumed by the facility is solely used for running the IT equipment. However, achieving a PUE of precisely 1 is extremely challenging, and most data centers have PUE values greater than 1.

Importance of PUE Value

A lower PUE value indicates higher energy efficiency. For example, a data center with a PUE of 1.5 means that for every 1.5 units of total power consumed, 1 unit is used by the IT equipment, and 0.5 units are consumed by the cooling, lighting, and other non-IT systems. Data center operators strive to minimize PUE by implementing energy-efficient infrastructure, optimizing cooling systems, using efficient power distribution, and employing different techniques to reduce energy consumption and waste.

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What is waste heat recovery energy?

Waste heat recovery is the process of capturing and reusing the heat that is generated by industrial processes or combustion, which would otherwise be lost to the environment. This captured heat can then be used to generate electricity, heat buildings, or power industrial processes. Waste heat recovery can be applied to a wide range of industries, including power generation, petrochemical, and manufacturing, and can lead to significant energy savings and reduced greenhouse gas emissions.

Waste heat recovery can be done by using techniques such as thermoelectric generators, Organic Rankine cycle, and Kalina cycle systems, and heat exchangers. These systems can capture waste heat from sources such as flue gases, hot water, or steam and convert it into usable energy.

Overall, waste heat recovery can help to increase the overall energy efficiency of industrial processes, reduce costs, and reduce the environmental impact of these processes.

For Further Reading

What is a pipe and what are the types of Pipes?

What is a Pipe?
According to the Merriam dictionary, a pipe is defined as a long tube or hollow body for conducting a liquid, gas, or finely divided solid or for structural purposes. From the engineering perspective, pipes are defined as circular tubular products used for conveying fluids (liquids, gases, and fluidized solids). For transporting fluid, pipes are designed for a particular design pressure corresponding to design temperature. Various parameters such as pipe size, pipe thickness, pipe material, pressure withstanding capability, temperature withstanding capability, etc. are considered during piping design.

Applications of Pipes:
Different types of pipes are used in the industrial sector for different purposes. Oil & gas, process industries, chemical & petrochemical industries, food & beverage industries, energy & power industries, refineries & pipeline industries, HVAC industries, steel & infrastructure industries, and daily water sewerage line requires pipes to transport fluid from one place to another. In modern life, the use of pipes is so broad that we cannot imagine any industrial process without pipes.

Types of Pipes:
Due to the application of a large number of industries and processes, the types of pipes are many. The type of pipe is chosen based on various application factors. In this article, we will discuss the different types of pipes that are widely used in industries.

1. Based on the material of the pipes

Pipes can be classified based on the material which is used to produce the pipe during manufacturing. In general, there are two types of pipes:
1. a. Metallic Pipes
1. b. Non-metallic Pipes

1.a. Metallic Pipes
The pipes which are made of metal are known as metallic pipes. They can be categorized into two categories:

1.a.1. Pipes made from ferrous materials
1.a.2 Pipes made from non-ferrous materials

1.a.1 Type of Pipes made from ferrous materials:
Pipes made from ferrous materials are stronger and heavier. These category pipes are most suitable used for heavy-duty work to transport high pressure or high temperature even sometimes heavy fluids. The common application of pipes made from ferrous material is in the oil & gas industries, chemical & petrochemical, energy & power industries, and refineries & piping industries.  These pipes have iron as their main constituent element. Common examples of pipes made from ferrous materials are-

  • Cast Iron pipes
  • Carbon steel pipes
  • Stainless steel pipes
  • Alloy steel pipes
  • Duplex Stainless Steel (DSS) pipes
  • Ductile Iron pipes and so on.

1.a.2 Type of Pipes made from Non-ferrous materials:
Although these pipes are metallic, however iron is not the main constituent of these pipes. These pipes are usually made of copper, aluminum, brass, etc. Non-ferrous material pipes are mostly used in the process piping industry. The main reason behind that is these materials have excellent tensile strength. For example, pipes made of Nickel and Nickel alloys are ideal to use in extreme heat environments because of their resistance property, and it has a passivating oxide coating on their covering. Nickel-copper, nickel- Molybdenum, and nickel-chromium are the most common alloys of Nickel. Nickel and its alloys offer resistance against corrosion and oxidation. This material is suitable to use in applications where alkalis or storing caustic soda is present. It is generally utilized in seawater and mild atmospheric applications. Common pipes made from non-ferrous materials are-

  • Copper and copper alloy pipes.
  • Aluminum and Aluminum alloy pipes.
  • Nickel and Nickel alloy pipes.
  • Titanium and titanium alloy pipes.
  • Zirconium and Zirconium alloy pipes.

1.b. Non-metallic Pipes
Non-metallic pipes are widely used for services where the temperature is not very high. Non-critical services like water industries and drainage systems make use of most of the non-metallic pipes. Common non-metallic and widely used pipes are:

  • Polyethene (PE) plastic pipe/ high-density polyethene (HDPE) Pipes
  • Polyvinyl chloride (PVC) / uPVC/ CPVC Pipes
  • PP pipes
  • Reinforced thermoplastic pipes or RTPs
  • ABS Pipes
  • Composite pipes like GRE/GRP/FRP Pipes
  • Cement and Asbestos Cement Pipes
  • Vitrified clay pipes

The main advantages of reinforced plastic and composite pipes are that they are highly corrosion resistant and durable. While metallic pipes are usually designed for up to 25 years of service. Composite and Reinforced plastic pipes can easily serve up to 50 years. However, their main limitation is the temperature. Non-metallic pipes are not suitable for high-temperature applications. Cement pipes, manufactured from reinforced concretes are usually used for stormwater, gravity service, irrigation industries, and culverts.

2. Types of Pipes based on industry application
As pipes are used in a wide range of industries, therefore these also can be classified based on the industry application. The major types of pipes based on industry applications are-

2.a. Pipes for the Plumbing industry
2.b. Pipes for Chemical and Power industries
2.c. Pipes for the Pipeline industry

2.a Types of Pipes for the Plumbing industry
Pipes are essential to supply water to the kitchen tap or to drain wastewater to the sewage system. These types of drainage and delivery systems have been around since ancient times. In modern times, the common plumbing pipes are PVC pipes, PEX pipes, Copper pipes, ABS pipes, Cast Iron and galvanized steel pipes, etc. They are mainly used for water distribution purposes.

2.b. Types of Pipes for Chemical and Power industries
These types of pipes are suitable for high-temperature and pressure applications. Mainly pipes made from ferrous materials are used in the chemical & petrochemical industries, power & energy industries, steel industries, and oil & gas industries. The chemical and power industry pipes are designed by following codes like ASME B31.3, ASME B31.1, and also other international standards and codes. They are usually selected based on their ability to sustain pressure, temperature, corrosion resistance, etc.

2.c. Pipes for the Pipeline industry
Pipes used in pipeline industries are usually known as line pipes. These pipes are designed by API 5L standard. There are various grades of API 5L pipes that are used to convey oil, gas, or water through pipelines. Other types of pipeline materials are SS, DSS, SDSS, GRE, FRP, etc.

3. Types of Pipes depending on the fluids transported

As you already know the main purpose of pipes is to transport fluids from one point to another, therefore depending on the type of fluid used to transport, pipes can be categorized as-

  • Water Pipes those transport water.
  • Gas pipes transport gaseous substances such as methane gas in the gas power plant.
  • Steam pipes transport steam such as steam in the steam power plant.
  • Vapor pipes transport different vapors of products such as vapor chemicals in the chemical industry.
  • Oil pipes transporting crude or processed oils.
  • Hydrogen pipes carrying hydrogens.

4. Types of Pipes depending on the manufacturing process
Pipes can also be classified based on the manufacturing process. These are again sub-categorized depending on the material of the pipe. For example, Metallic pipes can be categorized as-
4.a. Seamless pipes
4.b. Welded pipe
        4.b.1 Electric resistance welded (ERW) pipes
         4.b.2 Longitudinal Submerged Arc-Welding (LSAW) pipes

4.a. Seamless pipes
The most common types of seamless pipes are:

  • ASTM A106, A333, A53, and API 5L (CS and LTCS pipes)
  • ASTM A312 Series 300 and 400 (SS pipes with grades 304, 316, 321, 347)
  • ASTM A335 Grades P5 to P91 (Alloy steel pipes)
  • ASTM A790/A928 (DSS and SDSS pipes)
  • Nickel alloys (Inconel, Hastelloy, Cupronickel, Monel, Nickel 200)

In general, pipes with a diameter of less than 16 inches are seamless, and larger diameter pipes are welded. Seamless pipes are preferred due to the absence of the weld seam which is considered a weak point. However, they are costlier than welded pipes. Also, for large-diameter pipes, producing seamless pipes becomes difficult.

Carbon steel pipes (A53, A333, A106, and API 5L) have the largest market share since they are cheaper and suitable for a wide range of applications ranging from -29 Deg C to 427 Deg C.

Similarly, Glass Reinforced Plastic (GRP) pipes are classified as-

  • Filament winding GRP pipes
  • Continuous winding GRP pipes
  • Helical Filament winding GRP pipes

4.b. Welded pipe
4.b.1. Electric resistance welded (ERW) pipes
4.b.2. Longitudinal Submerged Arc-Welding (LSAW) pipes

Final Words:

Different types of pipes are used in various industries. The properties of those pipes are different based on their materials and compositions. Therefore, the types of pipes are very broad and there are various parameters that contribute to the classification of pipes. However, the most widely accepted pipe classification is based on the material used to fabricate the pipe. To buy different types of pipes you can visit Iminning Tuberia Industrial.

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Inside of a data center

What are the main components of a data center?

Over time, the usage of data is increasing exponentially. For on-time availability of online data and applications, the number of data centers is also increasing. If you already have a basic idea of a data center, you may know a data center is a structure that houses an organization’s shared IT operations and equipment to store, process, and distribute data and applications. Data centers are important to the continuity of everyday operations since they store an organization’s most critical and proprietary assets.

The requirements and architectures of a data center can differ considerably. For example, a data center built for a government facility may store classified data for a dedicated purpose. Whereas commercial data center facilities built by cloud service providers like Google and Amazon can store data and provide cloud service and maintain different levels of security, infrastructures, power backup systems, and so on. Therefore, the components of the data centers can vary significantly based on the purpose, size, and tier of the data centers. Regardless of the purpose, size, and data center tiers classification, the design of data centers needs to be optimized by investments for the facility and the equipment it consists of.

Here is the list of the core components with a brief description of a data center:

1. Overall Facility – The overall facility consists of the usable space available for IT equipment, support infrastructure, heating system, cooling system, power supply system, round-the-clock monitoring system, security system, and administrative systems. In addition, there may have space for the storage area of emergency consumables such as power cables, network cables, etc. As the data centers are one of the most power density facilities, therefore, the optimization of the power consumption and space, including data center space is a vital issue during the design of the overall facility.

2. IT components – The IT components of data centers consist of computing hardware, racks, storage systems, servers, networking systems, routers, switches, and various security elements, such as firewalls. In addition, data centers also consist of security surveillance systems, and data center operation and monitoring systems.

3. Support infrastructure – The typical uptime of four tiers data centers ranging from 99.671% to 99.995% is defined by the Uptime Institute. Therefore, the support infrastructure of the data centers needs to ensure the highest possible availability. for equipment contributing to securely sustaining the highest availability possible. Some components for supporting infrastructure include:

  • Environmental control – To control the temperature, humidity, and airflow in the data center there consists of a computer room air conditioner (CRAC) unit, computer room air handling (CRAH) unit, and exhaust systems.
  • Uninterruptible Power Sources (UPS) – To maintain the uninterruptible power in the facility there consist of battery banks, backup diesel generators, and redundant power sources.
    • Physical security systems – For the physical security of the data centers there consist of video surveillance systems, and biometric authentication systems.

4. Operations & Maintenance Team – To maintain round-the-clock operation the data center also has data center operators, technicians, and network engineers to monitor operations and maintain IT and infrastructure equipment. It also works for incident management, front-line support for firefighting, administrative works, service works, etc.

These are the major components of data centers. However, there are also additional components that are also very important for the smooth operation of a data center. If you have any questions or comments, feel free to write them down.

data center

What is a data center?

A data center is a structure that houses an organization’s shared IT operations and equipment in order to store, process, and distribute data and applications. Data centers are important to the continuity of everyday operations since they store an organization’s most critical and proprietary assets. As a result, data center security and reliability, as well as the information they contain, are among an organization’s top considerations.

Data centers used to be tightly managed physical infrastructures, but the public cloud has changed that. Most modern data center infrastructures have evolved from on-premises physical servers to virtualize infrastructure that supports applications and workloads across multi-cloud environments, with the exception of regulatory requirements that require an on-premises data center without internet connections.

The Function of Data Center
The data center is an important infrastructure of any organization, as they support corporate applications and provide services like:

  • Data storage, administration, backup, and recovery are all important aspects of data management.
  • Email and other productivity applications
  • E-commerce transactions with a high volume
  • Artificial intelligence, machine learning, and big data
  • Providing support for online gaming communities

According to several research and reports, there are more than 7 million data centers in the world now. Almost every company and government agency either creates and maintains its own data center or has access to another’s, if not both. Many choices are available today, including renting servers at a colocation facility, employing third-party data center services, or using public cloud-based services from Google, Amazon, Microsoft, and Sony.

The Basic Components of Data Center IT systems
The structures and requirements of data centers might be somewhat different. A data center created for a cloud service provider like Amazon, for example, meets different facility, infrastructure, and security criteria than a wholly private data center, such as one built for a government facility dedicated to securing sensitive data. An effective data center operation, regardless of classification, is achieved through a balanced investment in the building and the equipment it houses. Furthermore, because data centers frequently store an organization’s business-critical data and applications, both the facilities and the equipment must be protected against intrusions and cyber attacks. Routers, switches, firewalls, storage systems, servers, and application delivery controllers are the empirical components of a data center design.

The following are the five major elements that must be present for a data center IT system to work properly:
a) Application: It’s a computer program that provides the reasoning for performing calculations.
b) Database management system (DBMS): A systematic method to store data in an orderly table that is interlinked to each other is provided by a database management system (DBMS).
c) Host or Compute: A computing platform that works with an application database.
d) Storage: A storage device is one that saves data consistency for later use.
e) Network: A data channel that improves communication between all of its networked devices.

Types of Data Center Facilities
The growth and classification of various different types of data center facilities have resulted from the expansion of data center infrastructure. Here are some types of data center facilities-
a) Enterprise Data Center Facilities: These are facilities that are conventionally organized and owned and controlled by a single company. These are usually on-site, and maintenance, IT deployments, hardware upgrades, and network monitoring are all overseen by an in-house team.
b) Colocation Data Centers: A colocation data center is a shared data center where an organization can rent space for servers and other hardware. The advantages of colocation over in-house data centers include that the facility provides the building, power, HVAC, internet bandwidth, and physical security, while you (the customer) are responsible for providing and maintaining the hardware.
c) Cloud Data Center — In recent years, this sort of data center construction has grown in popularity. A cloud data center is an off-premises facility that your firm may use over the internet, but you are not responsible for managing the equipment.
d) Managed Data Centers: A corporation rents the physical infrastructure while a third-party managed service provider oversees the hardware and facility in a managed service data center arrangement.

For more information, you can watch this video on Anixter youtube channel:

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5S in 6 Sigma

What are the 5S in Six Sigma?

In a work environment, we cannot operate in a haphazard manner. It increases waste, reduces productivity, impacts delivery, and above all, results in customer dissatisfaction! So, by applying the 5S technique, we can solve the problem.

What is 5S?
The term came from the Japanese designer (at Toyota Production System) Taichi Ohno and Shigeo Shingo. 5S is a set of 5 Japanese words starting with S. Translated into English, all the words start with S as well. The 5S’s sequenced as a series of 5 steps as follows –

Step 1: Sort [Seiri]
In this step, the 5s concept practitioner has the responsibility to go through all the equipment, tools, and resources they have and determine which equipment or resources have to be retained on the work floor and which resources have to be eliminated. When they find tools that are not relevant to their work they can simply place back that equipment into the concerned departments. If they feel that some resources need to be completely eliminated from the workspace, then they have to put a red tag on that particular item and get authorization or permission from their senior officials before they dispose of it or recycle the item. In simple words, the practitioner has to segregate the important or useful things from the unnecessary thing and discard the unnecessary.

Step 2: Straighten or Set in Order [Seiton]
In this step, the 5S practitioner has to re-organize their workplace after eliminating unnecessary tools and equipment. Here the practitioner follows the simple philosophy of “a place for everything, and everything in its place”. This will help the other staff members locate the required resources easily and swiftly. This concept can be applied to any sector. In other words, the practitioner of 5S concepts arranges all the resources and tools in a systematic manner.

Step 3: Shine [Seiso]
In this step, the practitioner ensures that the equipment and tools are tidy and can be readily used by other staff members. If this concept is applied in the information technology sector, then the practitioner has the responsibility to delete all the irrelevant files and folders. In simple words, this concept focuses on tidiness and cleanliness in the workplace.

Step 4: Standardize [Seiketsu]
The practitioner can combine similar work activities in their facility and allot a workspace for that particular process in the work facility. For instance, if there are five lathe machines scattered across different locations doing the same work, then the practitioner can place all these units in one place so that better results can be achieved through constant monitoring of work processes. This concept can be applied in any sector to reduce redundancy.

Step 5: Sustain [Shitsuke]
This is the final step or stage in the 5S concept implementation. In this stage, the practitioner has to ensure that tools/resources are in neat and tidy condition and are placed where they are meant to be.

Project management

What are the steps for completing a successful project?

Here are the 5 steps for completing a successful project.

1. Create a high-performing team
2. Planning
3. Execution
4. Keep tracking the team and work schedules
5. Keeping the business in mind

For example, you want to create an EV-car factory. Your first step would be, to create a high-performing team. The project manager will make a plan for how to make the car factory with that high-performing team.

Then the work execution will be started. This is the main step of the project. However, for the final result of the project, you need to keep tracking the team and work schedules. At the same time, you need to keep in mind the budget, business, and final deliverables.

Crankcase ERV

What is the function of an explosion relief valve (ERV) in a crankcase?

Crankcase overpressure relief valves have three functions:

(1) Rapidly relieve excess pressure inside the crankcase
(2) Prevent flame inside the crankcase from escaping and causing further damage
(3) Rapidly close after the crankcase pressure is relieved to prevent the air from entering into the crankcase.

Figure: Crankcase overpressure relief valve operation.

The figures show that the relief valves have a light spring that holds the valve tightly against its seat. The pressure inside the crankcase is relieved, and the spring closes the valve automatically. Figures show an image of a properly operating crankcase relief valve. The valve is still closed on the left of the picture while an internal explosion is about to open. On the right, the internal pressure has forced the valve open, compressing the spring while the hot pressurized gas, but not the flame, is vented to the atmosphere. Once the pressure is relieved, the compressed spring closes the valve.

Figure: ERV in the industry.

API 618 requires a relief area to crankcase volume ratio of 3.0 in²/ft³ (683 cm² /m³), which is higher than any of the engine standards. With properly sized and installed overpressure relief valves, experience has shown that the risk of damage and injury from crankcase explosions can be eliminated. Most compressor and engine manufacturers offer them as standard equipment on large machines and options for smaller frame sizes.

Final Words

The crankcase explosion relief valve (ERV) rapidly relieves excess pressure, prevents flame, and rapidly closes after the crankcase pressure is relieved.

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2. Nuclear energy

Flow control valve

Why is a bypass line required for the control valve?

A bypass line may or may not be required during installing of a control valve in the piping of a process plant. Unless otherwise required, the necessity of installing a bypass line is determined by the P & ID creator (process engineer) in consideration of safety, operability, maintainability, economy, etc. Also, the process licensors and customers may be determined by the above requirements.

Therefore, in this article, I shall explain when a bypass line is necessary and whether it needs to be installed. In addition, we will also explain the points to keep in mind when installing a bypass line. By clearly stating the criteria for the necessity of bypass lines in a book that summarizes the concept and further describing it in the P & ID legend sheet (lead sheet), the process design department and the piping design department have a common understanding and are surely reflected in the design.

When installing a bypass line is required?

Bypass lines are often required at the control valve during plant operation. In a large process plant, it takes time to start up or shut down the entire process. Before the regular operation time, the production volume of the product (fluids such as steam or gas) needs to escape from the prime mover. So, installing a bypass line to the control valve can continue the operation.

Supplement: As for the pressure-equalizing line and pressure-equalizing valve installed around the high differential pressure control valve, the purpose of the installation is different from the above, so the consideration explained in this article is not necessary. In such a case, when performing maintenance of the control valve, close the block valves before and after the control valve, remove the control valve, and manually adjust the opening of the bypass valve to adjust the flow rate and control the operation of the plant.

When is a bypass line not required to install?

Depending on the fluid to be handled and the operating concept of the entire plant, troubles (leakage, erroneous operation, etc.) caused by installing a bypass line may not be tolerated. In such cases, the bypass line will not be installed even if the control valve has to shut down the plant for maintenance. In addition, from the viewpoint of the economy, there are cases where a bypass line is not installed to reduce the amount of piping work and the construction cost.

The above is decided by comprehensively considering operability and maintainability, construction cost, and operating cost, so it is necessary to consult with customers and related departments in good consultation. If a bypass line is not installed, an operation handle (hand-wheel) may be provided on the control valve as shown above to enable manual operation on-site if necessary. However, when selecting a control valve, consider whether the operation case at the low opening and high opening during unsteady operation is covered without bypass (whether the control valve is of the type with such rangeability).

In addition, as shown in the above figure, the control valve, including the cutoff circuit, often does not have a bypass line. We are considering the risk that dangerous fluid will flow out of the bypass line even though the broken circuit is working due to the opening due to the erroneous operation of the bypass line.

Points to be considered during installation of a bypass line

The flow coefficient (Cv) value
– of bypass valve ・ Countermeasures against the erroneous operation
– of bypass valve ・Operability of the bypass valve

Value of Bypass valve flow coefficient (Cv)
Since it is necessary to adjust the opening of the manual valve of the bypass line, the globe valve is basically selected. In principle, the same Cv value as the control valve is selected. However, depending on the operating case, it is necessary to select a valve that covers the low opening range and high opening range as necessary. The Cv is a universal capacity index and is simply defined in terms of U.S. gallons of water per minute at 60°F (or 15℃) that will flow through a valve with a pressure drop of 1 psi (or 6894.76 N/m2).

Countermeasures against the erroneous operation of the bypass valve

If the bypass valve is inadvertently opened by operation during operation, there is a risk that the operation will be disturbed, leading to plant failure or emergency stop. It needs to be designed properly. For example, removing the manual handle of the bypass valve during plant operation and using the Locked Open / Close specification are effective measures to prevent erroneous operations. It is also important to keep in mind the effect of opening the bypass valve by mistake and letting it flow back through the valve. If backflow is unacceptable, installing a shut-off valve on the upstream side is necessary.

Bypass valve operability

It is also necessary to think about the field indicators (pressure gauge, thermometer) necessity for operating the bypass valve should be installed in a place that can be seen from the operating position. For that purpose, it is necessary to consider the on-site target indicator by noting “In View” on the P & ID and clearly stating the relationship with the target bypass valve. It is also important to secure a space between the actuator and accessories and the bypass line, considering the maintainability and operability of the control valve.


In this article, I explained the idea of ​​the necessity of the control valve bypass line. Here is the summary of the article-
A bypass line may or may not be installed when installing a control valve in piping. Unless otherwise required, the necessity of installing a bypass line is determined by the P & ID creator (process engineer) in consideration of safety, operability, maintainability, economy, etc. Also, the process licensors and customers may determine the above requirements. By clearly stating the criteria for the necessity of bypass lines in a book that summarizes the concept and further describing it in the P & ID legend sheet (lead sheet), the process design department and the piping design department have a common understanding and are surely reflected in the design.

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