In industrial piping systems, globe valves and gate valves are two of the most commonly used shutdown valves. Although both are designed for starting and stopping fluid flow, they differ significantly in structural design, operating principles, application scenarios, and overall performance. Understanding these differences helps engineers make informed selections that ensure system efficiency, reliability, and cost-effectiveness. I. Key Differences in Structure and Operating Principles 1. Different opening and closing mechanisms Globe Valve: The disc moves up and down along a path perpendicular to the flow direction. Shutoff is achieved when the disc and seat sealing surfaces come into full contact. Gate Valve: The gate moves vertically in a manner similar to a “gate” that is either fully open or fully closed, with sealing achieved through surface compression. This means that globe valves are suitable for precise throttling, while gate valves are mainly used for full open or full shut service. 2. Flow path design differences A globe valve has an S-shaped flow path that forces the medium to change direction, resulting in higher flow resistance. A gate valve features a straight-through flow path with minimal resistance and low pressure drop, making it better suited for long-distance transmission. II. Differences in Application Scenarios 1. Throttling vs. On/Off Service Globe valves can be used for throttling and flow regulation, making them suitable for applications requiring high sealing performance and precise flow control, such as steam, cooling water, and various process media. Gate valves are not suitable for throttling, as operating them in a partially open position may cause gate vibration, damage to the sealing surfaces, and fluid-induced impact. Gate valves are ideal for large-diameter pipelines where low flow resistance is required and switching frequency is relatively low, including oil transportation, water supply and drainage, and power plant systems. 2. Size range and installation space Globe valves are generally used in small to medium sizes (more common below DN50). Their body structure is heavier and requires more installation space. Gate valves are suitable for medium to large sizes. Due to their simpler design, they offer a cost advantage in larger dimensions. III. Sealing Performance and Pressure Ratings 1. Differences in sealing surface design The globe valve features a tapered sealing surface, which achieves tight shutoff through axial compression, making it easier to obtain reliable sealing performance. The gate valve uses either parallel or wedge-type sealing surfaces. Its sealing effectiveness depends largely on the pressure applied by the gate and is more influenced by the system’s medium pressure. 2. Pressure and temperature adaptability Both valve types are suitable for medium- to high-pressure and high-temperature applications....
Butterfly valves are widely used in industrial piping systems due to their compact structure, lightweight design, and quick operation. They are commonly applied in water treatment, chemical, power, oil, and gas industries. However, when dealing with industrial standards across different countries and regions, selecting a butterfly valve that meets the relevant specifications is crucial. This article provides a detailed analysis of butterfly valve design and selection requirements based on three key standards: API 609, ISO 5752, and GB/T 12238. 1. API 609 — American Petroleum Institute Standard API 609 is the American Petroleum Institute (API) standard for metal-seated butterfly valves, primarily used in the oil, gas, and chemical industries. The standard defines valve structure, materials, dimensions, and pressure ratings to ensure reliable performance under high temperature, high pressure, and corrosive media conditions. Key points include: ● Pressure Ratings: Covers Class 150 to 1500, accommodating various service conditions. ● Body and Disc Design: Metal-to-metal sealing requires precise alignment between disc and seat to prevent leakage under high temperature or high pressure. ● Testing and Inspection: Includes shell tests, seat leakage tests, and operational performance checks to ensure valve safety and reliability. For high-temperature steam or high-pressure oil and gas pipelines, selecting a butterfly valve compliant with API 609 can significantly reduce leakage risk and extend equipment lifespan. 2. ISO 5752 — International Standard Organization Standard ISO 5752 is the International Organization for Standardization (ISO) standard that specifies end dimensions and flange connection sizes for valves. It defines the face-to-face dimensions, flange sizes, and connection methods for butterfly valves, providing a consistent interface specification for industrial users worldwide. Key points include: ● Face-to-Face Dimensions: Specifies valve lengths for different nominal diameters to ensure compatibility with piping systems. ● Flange Dimensions: Ensures valves match international standard pipe fittings, such as ANSI or DIN flanges. ● Interchangeability: Butterfly valves designed according to ISO 5752 can be replaced or serviced globally without redesigning the pipeline interface. ISO 5752 is particularly suitable for multinational engineering projects, ensuring the universality of butterfly valves across different plants and systems. 3. JB/T8527 — Chinese National Standard JB/T8527 is the Chinese national standard specifying the dimensions, structure, and testing requirements for metal hard-seal butterfly valves. It is widely applied in domestic industrial projects such as water conservancy, power, and petrochemical industries, serving as an important reference for procurement and acceptance. Key ...
Check valves are often considered the most “quiet” yet essential components in a piping system. Their primary function is to prevent backflow and safeguard pumps, compressors, and the overall stability of the system. However, in real-world applications, poor sealing—commonly referred to as “leakage”—is one of the most frequent and frustrating issues encountered in check valve operation. When a check valve fails to seal properly, it can reduce system efficiency, trigger pressure fluctuations, cause water hammer, and even damage critical equipment. This article breaks down the technical causes behind check valve leakage and offers practical diagnostic and corrective measures to help you quickly identify and resolve sealing problems, even under challenging operating. 1. Why Does a Check Valve Fail to Close Properly? Common Causes Explained 1. Presence of Particles or Solid Impurities in the Medium Solid particles can become trapped between the disc and the seat, preventing full contact and causing slight or even noticeable leakage. Typical signs include: ● Significant leakage at small opening positions ● Leakage decreases after cleaning 2. Disc Wear or Seat Damage Frequent cycling, corrosive media, or high-velocity flow can wear the sealing surfaces, resulting in scratches, pits, or deformation. This issue is especially common in high-temperature steam systems. 3. Incorrect Installation Direction or Insufficient Tilt Angle Although it may sound like a basic mistake, incorrect installation still occurs on many job sites. Since check valves rely heavily on gravity and flow direction, improper installation prevents the disc from returning to its closed position smoothly. 4. Flow Velocity Too Low to Create Adequate Differential Pressure A check valve opens through fluid flow. When the flow rate is too low, the disc may flutter or fail to close completely, leading to leakage. Common scenarios include: ● Insufficient straight-pipe length ● Frequent pump start/stop ● Poorly designed low-flow systems 5. Disc Sticking or Hinge Mechanism Not Operating Smoothly In swing check valves, rust, corrosion, or lack of lubrication at the hinge pin or disc connection may cause sticking, preventing full closure. 6. Thermal Deformation of Sealing Surfaces Due to Temperature Fluctuations In high-temperature conditions such as steam service, thermal expansion and contraction can slightly deform sealing surfaces, resulting in an imperfect seal. 2. How to Quickly Determine If a Check Valve Is Not Closing Properly? 1. Abnormal Pressure Gauge Readings If the inlet pressure remains stable while the outlet pressure gradually rises, backflow caused by check-valve leakage is the most likely reason. 2. Pipe Vibration or Light Knocking Sounds This indicates that the disc is oscillating at high frequency, often due to insufficient flow velocity or a loose dis...
This 20 inch butterfly valve is plastic lined type one. Its PFA lined disc and its PTFE seat ring enable it a excellent corrosion resistant performance. With a gearbox, it is easy to drive.
Payment:
30% when order confirmed, 70% before shipmentProduct Origin:
ChinaColor:
CustomizationShipping Port:
Shanghai, ChinaLead Time:
30~60 days Ex Works after order confirmationMaterial:
A216 WCBMethod of Operation:
GearboxQuick Detail
|
Type |
Butterfly Valve |
|
Nominal Diameter |
20' |
|
Nominal Pressure |
150LB |
|
Construction |
Flat Flange |
|
Connection |
Lug Type; |
|
Operation |
Gearbox |
|
Design & Manufacture |
API609 |
|
End to End Dimension |
ASME B16.10 |
|
Flange Dimension |
ASME B16.5 |
|
Body Material |
A216 WCB |
|
Disc Material |
SS2205+PFA |
|
Media |
W.O.G |
Features
--Substantial PFA liners for 3" through 12" and PTFE liners for 14" through 24"
Well resistance to permeation leading to extension of product life and operator safety
--Low torque. Smaller operators taking up less space, ease of operation and cost savings with less expensive automation packages.
--Improved disc design leads to less deflection at higher pressures and tighter in-line seal.
Technical Drawing
Painting Check
Packing
Our Main Product Range
As an experienced supplier and vendor of industrial valves, Dervos supply cast steel valve, forged steel valve, cast iron valve, stainless steel valve, bronze valve, brass valve and alloy steel valve and so on, suitable for sea water, water, oil, and gas application.
If you are interested in our products and want to know more details,please leave a message here,we will reply you as soon as we can.
The PTFE fully lined butterfly valve is made of cast iron body and with gearbox operation. The 14 inch flanged valve has concentric type structure. Quick Detail Type Butterfly Valve Size 14'' Design Pressure 150LB Construction Concentric Type, PTFE Lined Connection Type Double Flanged Operation Gear Operated Design Code API 609 Face to Face ASMEB16.10 End Connection ASMEB16.5 Test & Inspection API 598 Body Material Cast Iron GGG40 Temperature Range -15℃~+150℃ Application Water, Oil, Gas Related Knowledge What is the advantage of fully lined butterfly valve? The main advantage of lined butterfly valve is that it can handle abrasive and corrosive application at a relatively lower cost. The PTFE or PFA flexible seat provide a zero leakage sealing performance. Plus, the lined material PTFE has strong corrosion resistance, stable performance, low friction coefficient, which make the lined butterfly valve has a long service life. How does Dervos control quality of raw material? Raw material plays an important role in product quality. Likewise, casting and forging affect valve quality a lot. That is why Dervos pay a lot of attention to foundries. We have an approval list of foundries and classify them by certificates, scale, process and materials. To meet different requirements from customers, we could even appoint suitable foundries for our customers.
20" 150LB butterfly valve is made according to API 609 standard. The valve body is made of WCB. Its connection mode is Lug. And it has turbine operation mode.
The DN100 safety valve, made of WCB and according to GB/T12241-2005, usually work as the over-pressure protection device that work under a steam, air, water or other non-corrosive medium.
The DN80 PN16 cast iron gate valve has face to face dimension as per DIN3202 F4 or DIN3202 F5. This GG25 gate valve is designed with resilient seat, non rising stem, bb, RF flange, suitable for water treatment application. Quick Detail Type Gate Valve Nominal Diameter DN 80 Nominal Pressure PN 16 ConstructionType Non-rising stem, Bolted Bonnet, Resilient Seat ConnectionType Flanged OperationType Handwheel Operation Body Material Cast Iron GG25 TrimMaterial Cast Iron Wedge, SS420 Stem, EPDM Seat Design Code DIN 3352 End to End Code DIN 3202 Flange Dimesion DIN 2501 Medium Water Origin China Design Feature 1.Resilient seat for good sealing performance 2.Low flow resistance and small pressure drop 3.Non-rising stem for installation space is limited 4.No limitation for flow direction of medium 5.Epoxy painting available for internal and external part of the valve for anti corrosive function Company Brief Introduction Specializing in valve industry over 10 years, Dervos becomes the leading vendor of gate, globe, check, ball, butterfly, plug valves and strainers. We serve oil and gas user such as LUKOIL, MOL, YPF with local partners. Dervos show its advantages in: 1. Our partnerships with tens of stable suppliers allow us to provide customers with a wide range of high-quality products at a competitive price. 2. Each order is under strict quality control with inspection reports before delivery. 3. We value delivery time as much as our customers do. With the powerful purchasing system, we follow each order closely to secure on-time delivery. 4. One-stop solutions will be offered in a timely manner
8”300LB Cast Steel Y Type Strainer is made according to ASME B16.34 standard. The valve body is made of ASTM A216 WCB. It has the structural characteristics of Y Type. Its connection mode is RF.
2" 900LB plug valve is made according to API 6D standard. The valve body is made of A995 5A. It has the structural characteristics of oil sealed and full bore. Its connection mode is RF. And it has lever operation mode.
The 6 inch stainless steel gate valve, designed as per MSS-SP-81, has the lug type connection per Class 150 and electric actuator. Quick Detail Type Knife Gate Valve Size 6'' Design Pressure ANSI 150 Construction Knife Type Gate Valve ConnectionType Lug Type OperationType Electric Actuator Body Material ASTM A351 CF8 TrimMaterial SS304 Design Code MSS SP81 Medium Water, Oil and Gas Origin China Related Knowledge What are knife gate valves used for? Knife gate valves are originally designed for paper industry. The knife gate valve is especially applicable for heavy liquids with solid particulates, like slurry liquid, that are most corrosive, erosive and abrasive. Compared to wedge gate valve, the knife gate valve has a shorter end to end dimension and lighter weight. Plus, the knife valve has a more sharpened disc to cut through slurry and viscous medium. Both wedge gate valve and knife gate valve can only be used for on-off function not for regulating the flow. Dervos Customer Service With Dervos customer service, you will not have any concern before, during and after buying valves. Pre-sales We will reply on time and also provide technical support upon your request. Order We will check the production details with factory and customers. Sales confirmation will also be sent. During production, we will also send weekly report to let you know the order status. Before shipment, delivery note will be sent to let you know the situation. 18 Month warranty Dervos is always responsible for their products. We will provide 18 months warranty to let our customers without concern.
The 12 inch 600LB trunnion mounted ball valve has gearbox, RTJ flange, fire safe design per API 607. The 3 piece ball valve is designed per API 6D. Design Feature & Benefit 1.Small flow resistance means less pressure drop 2.Simple valve structure and light weight 3.Diversified sealing material available, from metal material TCC, satellite, stainless steel to soft material PTFE, Teflon, Nylon, Peek and etc 4.Good performance of both metallic sealing and soft sealing 5.Convenient and swift operation of the valve 6.Easy to maintain due to renewable seat ring 7.When fully opened or closed, the valve sealing face is isolated from medium corrosion. 8.Wide range of application in terms of size and pressure rating Quick Detail Type Ball Valve Size 12" Pressure Class 600 Construction Trunnion Mounted Ball, Three-Piece Type, Side Entry Connection RF Flange Operation Gear Operated Body Material ASTM A105 Design & Manufacture API 6D Pressure & Temp ASME B16.34 Face to Face ASME B16.10 End Connection ASME B16.5 Test & Inspection Code API 598 Fire Safe API 607 Temperature Range -29℃~+200℃ Medium Water, Oil and Gas Origin China Material Specification No Part Name Carbon steel to ASTM Stainless Steel to ASTM WCB LCB CF8 CF8M CF3 CF3M 1 Underplate WCB LCB CF8 CF8M CF3 CF3M 2 Underplate Bolt A193 B7 A320 L7 A193 B8 3 Trunnion A182 F6 A182 F6 A182 F304 A182 F316 A182 F304L A182 F316L 4 Body A216 WCB A352 LCB A351 CF8 A351 CF8M A351 CF3 A351 CF3M 5 Bonnet Nut A194 2H A194 4 A194 8 6 Bonnet Bolt A193 B7 A320 L7 A193 B8 7 Cap A216 WCB A352 LCB A351 CF8 A351 CF8M A351 CF3 A351 CF3M 8 Gasket SS Spiral Wound/graphite or SS Spiral Wound/PTFE 9 Shaft Sleeve SS/graphite 10 Seat Ring RPTFE or POM 11 Ball A105/Ep.Cr or F6 A182 F6 A351 CF8 A351 CF8M A351 CF3 A351 CF3M 12 Seat A105/Ep.Cr or F6 A182 F6 A182 F304 A182 F316 A182 F304L A182 F316L 13 Spring 17-17PH(inconel for NACE)Ni-cr Alloy 14 O-Ring Viton 15 Stem A182 F6 A182 F6 A182 F304 A182 F316 A182 F304L A182 F316L 16 Sealing Cover A182 F6 A182 F6 A182 F304 A182 F316 A182 F304L A182 F316L 17 O-Ring Viton 18 Gear Actuator The material is according to ASTM standard Related Knowledge What is difference between floating and trunnion ball valve? The ball part of floating ball valve is movable. Under the pressure of medium, the ball has a certain displacement and presses on the sealing surface of outlet end to ensure its tight sealing. The floating structure is suitable for ball valve with small size and low & medium pressure rating. The ball part of trunnion mounted ball valve is fixed. Under the medium pressure, the floating seat will move towards the ball to ensure the sealing. The trunnion mounted ball valve is often with larger size and higher pressure.
2"x1/2" 600LB slimline monoflange is made according to ASME B16.34 standard. The valve body is made of A105N. It has the structural characteristics of BLOCK-BLEED-BLOCK and complies with NACE MR 0175. And The structural characteristics of the first and second isolation valves are: plug cover, open stem, needle valve, and handle operation. The structural characteristics of the exhaust valve are: plug cover, needle valve, with tamper proof design. The structural characteristics of the drain valve: 1/4 "NPT-F with hexagonal threaded plug (NPT-M, ASME B1.20.1; MoC: F316L,CL.6000#). Its connection mode is RF*FNPT. And it has hand wheel operation mode.
Line blinds are utilized in pipeline systems when there is a need for either complete closure or unimpeded flow transition without a significant drop in pressure. The THD (Through-Hole Design) enables swift and seamless adjustments in position. The THD-slide variant boasts a multi-bolt configuration, making it easier to operate with reduced face-to-face dimensions. The inclusion of extra body bolts renders this style particularly well-suited for high-pressure applications.
2"x1 1/2" 150LB Casting Floating Ball Valve is made according to API6D standard. The valve body is made of ASTM A494 CU5MCUC. It has the structural characteristics of Reduced bore, floating ball. Its connection mode is RTJ. And it has hand wheel operation mode.
DN15 PN160 Forged Steel Flange Globe Valve is made according to BS 5352 standard. The valve body is made of A182-F5+STL. It has the structural characteristics of Face-to-Face (L): 170 mm. Its connection mode is EN1092-1D. And it has Handwheel operation mode.
Copyright © 2015-2025 DERVOS VALVE CO.,LTD.All Rights Reserved Blog / Sitemap / XML / Privacy Policy
