Category Archive: Check Valves
Natural Gas Storage
Natural gas storage and transmission systems are critical components of the energy sector. They allow companies in the industry to effectively balance natural gas production with its consumption. However, such systems are constantly exposed to the erosive flow of solid particles within natural gas that can damage the ductile metal of pipelines or valves, compromising their functionality over time.
Storage systems must also carefully control flow and pressure, requiring components like high-quality natural gas flow check valves and natural gas pressure check valves to help combat these challenges. Learn more about natural gas storage and how check valves maintain the reliability and integrity of natural gas infrastructure.
Basics of Underground Natural Gas Storage
The energy industry typically stores natural gas under pressure in various underground facilities due to the widespread availability of applicable sites. In the U.S., for example, most storage of this odor- and color-free gaseous hydrocarbon is located in emptied natural gas or oil field reservoirs near consumption centers. Salt cavern formations and aquifers are two other common below-ground storage options. To facilitate converting a depleted field from active production to a storage site for natural gas, this approach capitalizes on existing pipeline connections, wells, and gathering systems. Companies in the natural gas sector can also inventory the material above ground, storing it in its gaseous or liquid state within tanks.
However an organization chooses to stockpile its natural gas, its systems and components must be robust enough to handle the mechanical and chemical stresses of high-pressure gas storage and the erosive flow of natural gas transmission. Utilizing high-quality, erosion-resistant valve solutions to manage fluid flow and pressures in your pipelines helps ensure reliable, safe operations with optimized performance.
DFT®’s Check Valves for the Natural Gas Industry
While check valves are available in various sizes, end types, body materials, and pressure classes, the natural gas industry requires high-performance, long-lasting, low-maintenance valves with tight shutoffs to deliver dependable, continuous operation in the field.
At DFT® Inc., we offer an array of check valves that support our clients’ natural gas storage applications. Our PDC® Flanged Check Valve and GLC® Flanged Check Valve are two product options for the natural gas sector. They offer the following features and options:
- Single-piece valve body
- Protected spring with spring-assisted silent close
- Center-guided trim
- Stainless and carbon steel as standard body materials
- Availability in multiple sizes
- Vertical and horizontal installation capabilities
- Compliance with API Specification 6D
PDC®
DFT® offers the self-sizing PDC® Flanged Check Valve, designed specifically for natural gas applications. The PDC® valve is rated for ASME pressure classes of 150 to 1500 and is compliant with ASME B16.10 Face-to-Face.
Available in line sizes ranging from 2 to 26 inches, the PDC® is the model we recommend for reciprocating compressor systems in place of piston-type check valves. Our PDC® valve excels in managing the pulsating pressures that these compressors create when they discharge. It achieves this through a specialized pulse-dampening chamber that effectively eradicates valve chatter, a prevalent issue that can lead to premature seat wear and diminished valve performance.
GLC®
For natural gas lines utilizing other types of compressors, the short-pattern GLC® Flanged Check Valve is ideal. This dual-guided globe-style valve is engineered to minimize pressure loss while offering dependable, low-maintenance performance. Available in sizes 2 to 42 inches, the valve’s design enables a tight seal that’s pivotal in preventing leakage. Ensuring the integrity and efficiency of a natural gas system, the GLC® valve is rated for ASME pressure classes of 150 to 2500.
Advantages of DFT® Check Valves
DFT® has been at the forefront of check and control valve innovation for over 80 years. We utilize stainless and carbon steel in our valves for enhanced erosion and corrosion resistance as well as system longevity. With tens of thousands of valves in service across various sectors, DFT®’s expertise extends to natural gas, compressed gas transmission, and cryogenic liquids.
Our valves are not just components but critical investments in the safety and efficiency of natural gas infrastructure. By mitigating common problems within natural gas storage systems, our PDC® and GLC® Flanged Check Valves are designed to extend your equipment’s lifespan, supporting consistent and reliable operation within the demanding environments of the energy sector.
Natural Gas Check Valves From DFT®
DFT®’s extensive line of check valves is engineered to meet your unique natural gas storage and transmission requirements. Contact our technical team to learn more about our check valves and how we can support your natural gas operations, or request a quote today.
Check Valves in Semiconductor Fabrication
Semiconductors are highly sensitive electronic components that require precision and ultra-clean settings to produce. For creating and maintaining such high-purity conditions in semiconductor fabs, another name for fabrication facilities, manufacturers commonly utilize check valves in their fluid systems. Read on to learn more about the importance of dependable check valves in semiconductor fabrication operations as well as their specific benefits to the industry.
Importance of Check Valves in the Semiconductor Industry
To manufacture semiconductors, fabs require significant amounts of water and steam. Unidirectional check valves are critical components on a pump’s discharge in the fluid systems that deliver or transport these materials. These valves ensure tight seals, offering reliable protection against backflow while enabling smooth and efficient fluid flow. Without check valves, liquids and gases within these systems could flow backward, reverse-spin a pump’s impeller, and damage equipment.
Check valves are also responsible for preventing water hammer, or the surge in pressure that pipes experience as valves suddenly close or pumps shut down. When system fluids come to an abrupt halt, the impact force may cause the fluid to change direction. This is potentially very damaging to valves, pumps, and pipes, as water hammer can create pressure surges up to ten times that of a system’s working pressure.
These valves also keep contaminants from being introduced into the system’s supplies of pure water. While the water in fab processes isn’t the ultra-filtered, ultrapure water, UPW1, that applications like cleanrooms use, the UPW2 that fabs utilize is still exceptionally pure and sufficient for industrial processes.
Check Valve Applications in Semiconductor Fabrication
Wherever you find a pump in semiconductor fabs, you’ll also find a check valve. They support numerous applications within semiconductor manufacturing, including:
- Generating ultra-pure water
- Controlling water input to cleanroom (WICR) systems
- Processing wastewater
- Operating recirculation pumps
- Running cooling towers
- Cooling
- Rinsing
- Etching
WLC® Wafer Check Valves: The Ideal Choice for Semiconductor Fabs
WLC® Wafer Check Valves are advantageous for their:
- Leak-tight seal for contamination management. Our check valves maintain a tight seal that prevents leaks and removes process liquid and gas contamination risk. This ability is critical to semiconductor manufacturing operations.
- Axial flow design. DFT® engineers check valves for axial flow, which enables them to supply a non turbulent flow of process fluids with minimal pressure drop.
- Damage and downtime prevention. Our WLC® check valves prevent reverse flow, water hammer, and pressure spikes that might otherwise damage equipment, causing costly downtime. As process fluids slow and come to a stop, the spring in the valves’ design quickly seats the internal disc as part of a rapid, reliable closing mechanism.
- Corrosion protection. At DFT®, we only utilize high-quality materials. Our check valves consist of stainless steel, titanium, Hastelloy®, and other such metallurgies to ensure optimal resistance to harsh chemicals and corrosion.
- Silent operation. With their non-slam spring-assisted silent closing, WLC® check valves operate silently, with no slamming or chatter.
- Versatility. Our check valves are compatible with a diverse range of fluids, thermal conditions, and pressures involved in semiconductor fabrication.
- Flexible installation. A distinguishing feature of our check valves is the installation. Unlike a swing check valve, you can install these products vertically (flow up or flow down) or horizontally. This is particularly applicable to cooling tower installations.
- Longevity. These axial flow check valves are designed for long-lasting performance, with minimal maintenance required.
A benefit to partnering with DFT® is our proprietary sizing program. We can custom size our valves to your specific application. Other customization options involve material, pressure, temperature, and flow to support the system’s required cycle rate.
Supporting High-Quality Semiconductor Fabrication With DFT® Valves
Reliable check valves are vital to semiconductor fabrication operations, preventing reverse flow and water hammer while safeguarding equipment and process fluids. At DFT®, our team is backed by more than 80 years of experience helping clients solve their most complex fluid flow challenges. As evidence of our trusted expertise, DFT® has been badged at a major Semiconductor Manufacturer since 1997.
Our ISO 9001-certified company manufactures valves for quality, using methods like leakage rate and hydrostatic testing. Also, our valves are made of materials from certified sources to better create quality products. We balance off-the-shelf offerings with customized valves to ensure you have access to the ideal valve solution for your specific applications. DFT® also carries a significant amount of inventory, allowing us to commonly beat out the competition on lead times.
We take a client-focused, hands-on approach to business to form lasting partnerships with clients in the semiconductor industry and beyond. Contact us for more information on how our check valves support semiconductor fabrication or request a quote today.
PDC® Valves vs. Piston Check Valves
Pulse-dampening check valves, or PDC® valves, are designed for installation on the discharge side of a gas or air reciprocating compressor and feature a pulse-dampening chamber. With this pulse-dampened design, during the momentary pressure and flow increases and reductions that occur with a reciprocating compressor’s cycles, the PDC® valve’s disc remains in the open position, accommodating flow variations and eliminating chatter.
Allowing for either horizontal or vertical installation, these spring-assisted, nozzle-style check valves are used for air or gas and come in line sizes of 2″ to 26″ and ASME Classes 150 to 1500. As for material composition, the one-piece body of this flanged valve is available in either carbon steel or stainless steel, while the center guided trim is composed of stainless steel. You can choose between RF flanged ends or RTJ ends.
These high-performance silent check valves comply with API 6D, a specification set forth by the American Petroleum Institute to govern valve design, production, and testing for natural gas and petroleum applications. They also adhere to the standard ASME B16.10 face-to-face dimensions, as specified by the American Society of Mechanical Engineers.
Compared to piston check valves, PDC® valves offer multiple advantages. Read on to learn more about these valve types and how they differ to determine which is the best option for your needs.
Piston Check Valves
Another variety of check valves is the piston check, which can be used in gas or liquid piping systems. This valve type functions by using a weighted piston, gravity, and backflow pressure. The piston rises up as a result of forward fluid flow within the valve, but when it experiences backflow pressure, spring force pushes the piston seal into the seat to prevent reverse flow.
Some differentiating factors are that with the fluctuations in pressure, such as from a reciprocating compressor, the constant hammering of the piston is not only quite noisy, but over time, the continuous wear the valve incurs can reduce its performance and ultimately lead to premature wear, constant maintenance, or even failure. The internal flow of the piston check is considered a tortuous path, which affects pressure drop. Additionally, the piston check has multiple pressure-retaining components (leak paths), whereas the PDC® is a one-piece body.
DFT®’s PDC® Valves Are Built to Handle Reciprocating Compressor Discharge
At DFT® Inc., we manufacture our PDC® silent check valves for longer service life and quieter operation. The dampening chamber mitigates a compressor’s pulsed discharge for significant reductions in the wear and tear a piping system will experience. The valve’s unique shape offers the additional benefit of normalizing fluid flow exiting the check valve.
When you’re operating a piping system with an integrated reciprocating compressor, for example, this can cause high-frequency pressure cycling. An installed piston check valve would experience greater wear, impacting additional down-line systems, whereas the PDC® valve offers better protection and more dependable functionality for your application and equipment.
Learn More About Our PDC® Valves
Choosing PDC® check valves from DFT® over piston check valves can enhance the performance, reliability, and longevity of your piping system. This generally equates to a better return on your investment over the lifetime of the valve.
As a world-class manufacturer of control and check valves, DFT® has the multi-industry experience, the resources, and the commitment to excellence and innovation required to produce high-quality valves that address the challenges of each of our customers. We offer an extensive catalog of silent check valve options for solving problems such as water hammer. In addition to our PDC® model, we also have the following available:
- Threaded/socket weld check valves
- Wafer check valves
- Flanged check valves
- Butt weld check valves
- Sanitary check valves
- Restrictor check valves
- Vacuum breaker check valves
- Nickel-aluminum bronze (NAB) check valves
Whatever your application, DFT® is here to help you find the right valve for your unique requirements. Contact our team today to learn more about the PDC® silent check valve difference. You can also explore our PDC® product page or view a 3D animation of the PDC® pulse-dampening effect.
Join Us for an Exclusive Webinar on Check Valve Applications for LNG Service
Title: Check Valve Applications for LNG Service
Presented by: DFT Inc.
Hosted by: GlobalSpec
Date: September 18, 2024
Time: 10:00 AM EDT (7:00 AM PDT / 4:00 PM CEST)
As the demand for Liquid Natural Gas (LNG) continues to rise, understanding the infrastructure behind this vital energy resource is critical for engineers and industry professionals. LNG is a key player in today’s energy markets, known for its efficiency in storage and transport, making it an attractive option for power generation, industrial use, and transportation.
LNG’s operating conditions — including cryogenic temperatures, high pressures, and flow dynamics — place specific requirements on the equipment used in its processing systems. That’s why selecting the right check valve is paramount for ensuring system reliability and avoiding costly disruptions.
This webinar, presented by DFT and hosted by GlobalSpec, will provide valuable insights into the application of spring-assisted non-slam check valves within LNG service. The session will feature Arie Bregman, a seasoned valve industry expert with decades of experience in valve engineering, as he explores how check valves function within LNG processes and why their proper installation and sizing is critical for efficient system performance.
Why Should You Attend?
The webinar is geared toward valve professionals, engineers, and plant managers who are involved in LNG systems and valve selection. Attendees will gain practical insights that can be directly applied to improving operational reliability and efficiency.
Key Topics to be Covered:
- Understanding LNG Fundamentals: A brief introduction to the basics of LNG, its properties, including the processes and equipment used in liquefaction, storage, and transportation.
- Check Valve Applications in LNG: Gain insights into where and how check valves are used within LNG systems, focusing on key applications that optimize system efficiency and prevent flow disruptions.
- Optimal Valve Placement: Learn how strategic valve placement within LNG systems can significantly reduce wear, tear, and potential failures.
- Importance of Valve Sizing: Sizing check valves correctly can prevent common operational issues such as chattering and improper flow control. We’ll guide you through the critical considerations in valve sizing to ensure valves perform optimally.
- Industry Standards & Compliance: Familiarize yourself with the latest industry standards and specifications, ensuring your projects meet regulatory requirements and adhere to best practices.
Meet the Expert: Arie Bregman
Our speaker, Arie Bregman, brings nearly five decades of experience in the valve industry. From his beginnings with Nibco to significant roles at Jamesbury, Metso/Valmet, and DFT, Bregman has established himself as a respected voice in valve engineering. He holds a Master’s Degree in Mechanical Engineering from Worcester Polytechnic Institute and has served in leadership roles within the Valve Manufacturers Association of North America. His technical expertise and commitment to industry education make him the perfect guide to walk you through check valve applications in LNG service. DFT is pleased to welcome him back to present this special webinar on Check Valve Applications for LNG Service!
Don’t Miss Out!
Whether you’re a seasoned professional optimizing your current systems, or a valve professional seeking to deepen their understanding of valve applications within LNG processes, this webinar will provide insights about proper selection and application of check valves within LNG services. By attending, you’ll walk away with actionable knowledge to improve the efficiency and reliability of your operations.
Register now to secure your spot in this must-attend webinar on September 18, 2024.
Can’t make the date? Register and you will be notified when the webinar is available to watch on-demand.
Severe Service Check Valves
DFT® manufactures check valves for many applications, including severe service applications. Typically, when engineers think of severe service, they think of high temperatures and/or high pressures. However, severe service applications also include high cycling applications. We are going to explore two high cycling applications, including the challenges and DFT®’s severe service valve solutions.
Digester Service
The paper pulp digester is the primary equipment used in the production of chemical pulp. It is used to cook raw materials for papermaking (e.g., wood, grass, bamboo, and others) to produce pulp mainly containing cellulose by chemical interaction with the cooking liquor.
This process includes steam injection at up to 150 PSIG. The steam is pulsed into the digester several times per hour. While 150 PSIG is not considered severe, the constant pulsing can take a toll on equipment.
Digester Solutions
Several end users have experienced premature failure of traditional swing-type check valves in this application. When the swing check valves fail, the black liquor used to break down the pulp and the pulp itself would migrate upstream past the failed swing check and damage upstream piping and equipment.
The end users reached out to DFT® to develop an Axial Flow Non-Slam Check Valve solution to this problem. DFT® developed several styles of severe service check valves with special construction to handle this high cycling application. The DFT® solutions include the GLC® SS short-pattern flanged check valve, the Excalibur® SS a B16.10 long-pattern flanged check valve, and the WLC® SS wafer-style check valve.
All of these check valve styles have upgraded internal materials selected to withstand constant high cycling. The upgraded materials include 17-4 trim with a Xylan-coated one-piece welded disc stem assembly, 17-4 bushings, and an X-750 spring.
Compared to only getting several months of service life with the swing check valves, end users now get extended years of service life with the DFT® Axial Flow Non-Slam Digester Severe Service Valve solution.
Boiler Feedwater Service
All power plants—including natural gas-fired, coal-fired, and nuclear power plants—have boilers. The boilers generate steam to power turbines that generate electricity. Water must be heated in boilers to generate steam. The water is delivered to the boilers by boiler feedwater pumps.
Boiler feedwater is typically in the range of 180 °F to 225 °F. These temperatures would not be considered severe. However, depending on the design of the system in power plants, the temperature may be even higher, often 300°F to 350°F , especially if feed water is preheated by economizers or heaters using steam from the turbine or other heat recovery processes. Feedwater pump discharge pressures can vary between 700 and 1400 psi depending on boiler demand.
Check valves are installed between the outlet of the boiler feedwater pumps and the inlet of the boilers and/or deaerators. The check valves are installed to prevent backflow out of the boiler that can damage expensive feedwater pumps and other upstream equipment. Not only is this a high-cycling operation, but it is also a high-pressure application with varying pressures depending on boiler load. This is a very demanding application. As with the digester application, traditional swing checks typically experience a high failure rate in this application.
Boiler Feedwater Solutions
DFT® developed the WLC® BF specifically for boiler feedwater applications. The WLC® BF has upgraded hardened materials selected to withstand high pressure, pressure swings, and high cycling. The upgraded materials include a WL9 body, a 4 ribbed body construction, greater wall thickness, 410 trim, a one-piece welded disc stem assembly with Colmonoy-coated stem, carburized bushings, and an X-750 spring.
Compared to only getting several months of service life with the swing check valves, end users now get extended years of service life with the DFT® Axial Flow Non-Slam Boiler Feedwater Severe Service Valve solution.
Valve Types
DFT® offers the following valve types for digester, boiler feedwater, and other severe service applications. These valves are constructed from high-quality, heavy-duty materials with tight seals to withstand the harsh operating conditions of their application:
- DFT® Model WLC® BF (Boiler Feed): The DFT® Model WLC® BF wafer style check valve is for severe duty boiler feed service applications and other severe duty applications.
- DFT® Model GLC® SS: The DFT® Model GLC® SS is a severe service short-patterned flanged silent check valve designed for digester applications and other severe service applications.
- DFT® Model WLC® SS: The DFT® Model WLC® SS is a severe service wafer style check valve for digester applications and other severe service applications.
- DFT® Excalibur SS: The DFT® Excalibur SS is a severe service flanged silent check valve for digester applications and other severe service applications. This valve is B16.10 and a direct replacement for a swing check valve.
Severe Service Check Valves by DFT® Inc.
Severe service applications require specialized valve solutions. DFT® Inc. offers an extensive product line of robust severe service silent check valves specifically designed for these high-pressure and high-temperature environments. We are certified by ISO 9001:2015 and many other valve standards such as 3-A Sanitary Standards, Manufacturers Standardization Society (MSS), American Petroleum Institute (API) SPEC 6D, and European Pressure Equipment Directive (PED) to provide quality, long-lasting valves you can depend on.
Request a quote for your severe service valve solution today.
