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...
Payment:
30% T/T When Order, 70% T/T Before ShipmentProduct Origin:
ChinaColor:
CustomizationShipping Port:
Shanghai ChinaLead Time:
35~60 days Ex Works After Order ConfirmationMaterial:
Carbon SteelMethod of Operation:
Gear OperatedThe API 6D through conduit gate valve is designed with double expanding wedges, metal to metal seat and diversion hole for pigging. The valve has good performance on sealing, less flow resistance and is suitable for application with some solids or particles.
Quick Detail
|
Type |
Gate Valve |
|
Size |
18'' |
|
Design Pressure |
ANSI 600 |
|
Construction |
Double Expanding Wedges, Fully Metal Seat, With Diversion Hole |
|
ConnectionType |
RTJ Flange |
|
OperationType |
Gearbox Operated |
|
Body Material |
WCB |
|
WedgeMaterial |
A105+STL+ENP |
|
StemMaterial |
17-4PH |
|
SeatMaterial |
A105+STL+ENP |
|
Design Code |
API 6D |
|
Face to Face Dimension |
ASME B16.10 |
|
End Connection |
ASME B16.5 |
|
Pressure & Temp |
ASME B16.34 |
|
Medium |
Water, Oil and Gas |
|
Origin |
China |
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 through conduit slab gate valve, designed as per DIN standard, has the diversion hole for pipeline cleaning. The PN64 parallel disc gate valve is made of carbon steel with RF flange and handwheel. Quick Detail Type Parallel Slab Gate Valve Nominal Diameter DN 200 Nominal Pressure PN 64 Construction Parallel Slabe Gate Valve, With Diversion Hole, Bolted Bonnet, Resilient Seat Connection Flange Operation Handwheel Operation Body Material Carbon Steel Medium Water, Oil and Gas Origin China Design Feature 1.Parellel disc 2.Soft seat and metal seat for choices 3.Full bore design for pigging and less pressure drop 4.Firesafe design 5.Self relieving function 6.Grease fitting for seat and stem 7.Double block and bleed capability 8.With vent and drain port 9.Tight sealing performance Material Part Name Material Body & Bonnet A216 WCB, CF8, CF8M, CF3, CF3M Wedge Alloy Steel (face harden treated), Stainless Steel (with Co overlay) Stem Alloy Steel (face erosion-resistant treated) Seat Alloy Steel (face harden treated, beset F plastic), Steel (with Co overlay, best F plastic) Packing PTFE O-Ring NBR, FEP Sealing Grease
The DN100 through conduit slate gate valve is made according to EN558.It is ideal for pipeline applications requiring pigging capability.
It is a Carbon Steel full bore flat gatevalve with parallel wedge, DN250 PN100, made from LCC, one kind of low-temp carbon steel, which makes this valve capable to handle extreme working conditions.
The API 6D through conduit gate valve is designed with 600 LB flange and gearbox connection. Made of carbon steel WCB, the 20 inch gate valve has soft seat design without diversion hole.
10’’ ~ 24’’ 600LB gate valve is made according to API 6D standard. The valve body is made of A516 Gr70. It has the structural characteristics of parallel gate. The operation mode is gear operation.
3" 1500LB flat gate valve is made according to API6D standard. The valve body is made of ASTM A995 4A. It has the structural characteristics of BB, OS&Y, with diversion holes. Its connection mode is RTJ. And it has hand wheel operation mode.
The 16 inch cast steel gate valve with gearbox and 600LB RF flange is designed as per API 600. The bolted bonnet gate valve features in rising stem, resilient wedge and metal seat. Quick Detail Type Gate Valve Size 16" Pressure Class600 Construction Bolted Bonnet, Rising Stem, OS&Y, Flexible Wedge, Metal Seat Connection RF Flange Operation Gearbox Design Code API 600 Face to Face ASME B16.10 Flange End ASME B16.5 Pressure & Temp ASME B16.34 Test & Inspection API 598 Body Material A216 WCB TrimMaterial Trim 5 Temperature Range -29℃~+425℃ Medium Water, Oil and Gas Origin China Dimension & Material Class 600 NPS in 2 2 1/2 3 4 6 8 10 12 14 16 18 20 24 DN mm 50 65 80 100 150 200 250 300 350 400 450 500 600 L-L1 (RF-BW) in 11.5 13 14 17 22 26 31 33 35 39 43 47 55 mm 292 330 356 432 559 660 787 838 889 991 1092 1194 1397 L2 (RTJ) in 11.625 13.125 14.125 17.125 22.125 26.125 31.125 33.125 35.125 39.125 43.125 47.25 55.375 mm 295 333 359 435 562 664 791 841 892 994 1095 1200 1407 H (OPEN) in 18.625 21.75 23.375 28 1/16 38 3/16 44 3/16 52.375 59 13/16 68.125 72.25 90.125 98 13/16 119 mm 474 553 593 713 970 1122 1330 1519 1730 1835 2290 2510 3022 W in 9.875 9.875 11 13/16 13.75 19 11/16 22 1/16 28.375 24 24 24 24 30 30 mm 250 250 300 350 500 560 720 610* 610* 610* 610* 760* 760* WT (kg) RF 41 58 88 131 253 413 623 784 1288 1820 2150 2540 4080 BW 35 50 68 104 208 328 496 637 1120 1448 1828 2201 3360 *Manual gear operator is recommended No Part Name Carbon steel to ASTM Alloy steel to ASTM Stainless steel to ASTM WCB LCB WC6 WC9 C5 CF8 CF8M CF3 CF3M 1 Body A216 WCB A350 LCB A217 WC6 A217 WC9 A217 C5 A351 CF8 A351 CF8M A351 CF3 A351 CF3M 2 Seat Ring A105 A350 LF2 A182 F11 A182 F22 A182 F5 A182 F304 A182 F316 A182 F304L A182 F316L 3 Wedge A216 WCB A350 LCB A217 WC6 A217 WC9 A217 C5 A351 CF8 A351 CF8M A351 CF3 A351 CF3M 4 Stem A182 F6 A182 F6 A182 F304 A182 F304 A182 F316 A182 F304L A182 F316L 5 Bonnet nut A194 2H A194 4 A194 7 A194 8 6 Bonnet bolt A193 B7 A320 L7 A193 B16 A193 B8 7 Gasket SS Spiral Wound graphite or SS Spiral Wound PTFE 8 Bonnet A216 WCB A352 LCB A217 WC6 A217 WC9 A217 C5 A351 CF8 A351 CF8M A351 CF3 A351 CF3M 9 Backseat bushing A182 F6 A182 F6 A182 F304 A182 F304 A182 F316 A182 F304L A182 F316L 10 Stem packing Graphite or PTFE 11 Lantern A182 F6 A182 F6 A182 F304 A182 F304 A182 F304 A182 F304 A182 F316 A182 F304L A182 F316L 12 Gland Nut A194 2H A194 8 13 Gland Eyebolt A193 B7 A193 B8 14 PIN Carbon steel or Stainless Steel 15 Gland A182 F6 A182 F304 A182 F316 A182 F304L A182 F316L 16 Gland Flange A216 WCB A351 CF8 17 Stem Nut A439 D2 or B148-952A 18 Nipple Carbon steel or Stainless Steel 19 Retaining Nut Carbon steel 20 Hand Wheel Ductile Iron or carbon steel 21 Name Plate Stainless steel or Aluminum 22 H.W.Lock Nut Carbon steel
The DN100 3 way ball valve is isolating valve designed to redirect the service fluid flow rather than throttling or regulating purposes. Suitable for water, steam, gas, oil, crude oil, acid, alkali and other liquids and gases without mechanical impurities.
API 6D ball valve is designed with trunnion mounted ball and full bore structure. The flanged ball valve has 300LB design pressure and 8 inch nominal size with gearbox operation mode, conforming to NACE MR0175 requirement. Quick Detail Type Ball Valve Size 8” Pressure 300LB Construction Two-Piece Body, Full Bore, Trunnion Ball Connection RF Flange Operation Mode Gearbox Body Material A216 WCB Trim Material Ball/Stem F6a, Seat RPTFE Design & Manufacture API 6D Pressure & Temp Code ASME B16.34 End to End ASME B16.10 End Connection ASME B16.5 Inspection API 6D, API 598 Temperature Range -29℃~+200℃ Medium Oil, Water, Gas Dervos Packing Painting Test & Report Pressure Testing & Dimension Checking
20" 150LB wafer check valve is made according to API594 standard. The valve body is made of A351 CF8M. It has dual plate and built-in type structural features. Its connection mode is Wafer RF.
10" 150LB check valve is made according to BS1868 standard. The valve body is made of ASTM UNS N08031. It has the structural characteristics of bolt cover and swing type. Its connection mode is FF.
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.
Copyright © 2015-2025 DERVOS VALVE CO.,LTD.All Rights Reserved Blog / Sitemap / XML / Privacy Policy
