In industrial piping systems, gate valves are generally considered low-resistance isolation valves. When the valve is fully open, the gate is completely withdrawn from the flow path, allowing the fluid to pass through with minimal obstruction. However, from a strict engineering perspective, not all gate valves are classified as full port valves. If the seat bore is equal to or very close to the pipeline internal diameter, the flow experiences little or no restriction. In this case, the valve can be considered full port (or near full port). This design is commonly used in oil and gas pipelines, water transmission systems, and other applications where low pressure drop is required. If the seat bore is slightly smaller than the pipe internal diameter, a minor flow restriction will occur inside the valve. In such cases, the valve is more accurately described as reduced bore. This configuration is more common in smaller sizes or cost-optimized valve designs. In engineering practice, a simple selection logic can be applied: ● If the system requires minimum flow resistance or pipeline pigging, the valve bore must match the pipeline diameter. ● If the valve is used for general isolation purposes, most standard gate valves can already meet the required flow capacity. Therefore, a concise conclusion can be drawn: Gate valves are typically close to full port designs, but whether they are truly full bore depends on whether the seat bore equals the pipeline internal diameter. QA Q1: Are gate valves always full bore?Not necessarily. If the seat bore equals the pipe internal diameter, the valve can be considered full bore. If it is slightly smaller, it is classified as reduced bore. Q2: Why do gate valves have relatively low flow resistance?When the valve is fully open, the gate is completely removed from the flow path, allowing the fluid to pass through in a nearly straight line, which results in low pressure drop. Q3: Are gate valves suitable for high-flow pipelines?Yes. If the system requires low pressure drop, gate valves are commonly used. Q4: Is the concept of full port the same for gate valves and ball valves?Not exactly. For ball valves, the bore size is determined by the ball port diameter, while for gate valves, it is mainly determined by the seat bore diameter.
Large diameter ball valves are commonly used in industries such as petroleum and chemical processing, power generation, long-distance pipeline transportation, and large-scale water treatment systems. If installation is not performed correctly, it may lead to sealing leakage, valve jamming, or structural stress damage. Therefore, proper installation practices are essential to ensure long-term stable operation. 1. Pre-installation Inspection If pre-installation inspection is insufficient, operational failures are more likely to occur during service. First, inspect the valve body for transportation damage. If scratches, impact marks, or deformation are found on the valve body or sealing surfaces, installation should be stopped and the supplier should be contacted. Next, verify valve model, pressure rating, and connection standards. If the system design pressure does not match the valve pressure class, operational safety risks may occur. For example, if a low-pressure class valve is mistakenly used in a high-pressure pipeline system, the valve body may experience plastic deformation under water hammer impact. It is also necessary to check the condition of the ball surface and sealing rings. If there are scratches on the ball surface, sealing performance will be reduced. This is especially critical in gas transmission systems where micro-leakage is more likely. 2. Installation Direction Large diameter ball valves usually have a flow direction marking. If the installation direction is incorrect, the following problems may occur: If the fluid flow direction matches the design direction, the operating torque will remain more stable. If the valve is installed in reverse, the stem may experience increased mechanical load, which will accelerate stem wear during long-term operation. For double-seal bidirectional ball valves, although bidirectional flow is allowed, installation according to the marked flow direction is still recommended to ensure more uniform sealing stress distribution. In high-temperature or steam systems, if the installation direction is incorrect, thermal expansion may accelerate sealing ring aging. 3. Pipeline Stress Control Large diameter ball valves are heavy. If installed without proper support, additional bending moments may be transferred to flange connections. If pipeline systems experience axial displacement, pipeline supports should be installed for segmented fixation. If support structures are not provided, the valve body may bear long-term gravitational tensile load, eventually causing flange seal failure. It is generally recommended to install independent supports on both sides of large diameter ball valves. If the pipeline system is subject to thermal expansion and contraction, expansion compensation devices must be installed; otherwise, sealing surfaces may gradually fail. 4. Bolt Tightening Process Flange connections of large diameter ball valves usually ...
This year’s Dervos annual conference was noticeably more grand and well-organized than in previous years. In the morning session, each department delivered its annual work summary, reviewing key projects and achievements over the past year. Teams also openly shared the challenges encountered during implementation and the practical experience gained along the way. Through this cross-department exchange, everyone developed a clearer understanding of one another’s responsibilities and workflows, laying a stronger foundation for future collaboration and communication. In the afternoon session, the Outstanding Employee awards were presented. Each nominee shared their work achievements and practical experience, demonstrating a strong sense of responsibility and execution across different roles. It is precisely this proactive mindset, collaborative spirit, and down-to-earth working approach of Dervos employees that drives the team steadily toward its shared goals. Showing up on time every single day throughout the year — that’s quite an achievement. Ian has now received the Perfect Attendance Award for two consecutive years. During the annual conference, Dervos also presented medals and exclusive commemorative gifts to employees who have completed five years of service. Dervos values the long-term dedication and consistent commitment of its team members, and sincerely appreciates the trust and contributions they have made over the years. For many at Dervos, the company is not only a platform for professional growth, but also a stage where shared goals and collective efforts come to life. In the evening, the annual conference transitioned into the banquet segment. Performances and interactive games were seamlessly interspersed, creating a relaxed yet organized atmosphere. Laughter and cheers echoed throughout the venue, and in the moment the camera shutter clicked, the excitement and joy were captured in a single frame. Eric said: "Let’s dream together, DERVOS's dream. A dream where we all play a part, piece by piece, it becomes a reality." For Dervos, the annual meeting is not just about "summarizing the year," but about bringing our hearts together, strengthening our resolve in doing the same thing, and then continuing to move forward, step by step, with steady progress.
Payment:
30% when order confirmed, 70% before shipmentProduct Origin:
ChinaColor:
CustomizationShipping Port:
Shanghai, ChinaLead Time:
30~60 days Ex Works after order confirmationMaterial:
ASTM A352 LCCMethod of Operation:
no4” 150LB Butterfly Valve is made according to API609 standard. Its connection mode is RF.
|
Type |
Lug Butterfly Valve |
|
Size |
4” |
|
Pressure |
150LB |
|
Connection |
RF |
|
Body Material |
ASTM A352 LCC |
|
Design Norm |
API 609 |
|
Face to Face |
API 609 |
|
Flange dimension |
ASME B16.5 |
|
Test & Inspection Code |
API 598 |
|
Temperature |
-40~ 120°C |
|
Applicable Medium |
Water,Steam,Oil etc |
Features
1.Lug-style design allows easy installation between flanges and supports downstream piping during maintenance.
2.Constructed from LCC carbon steel, rated 150LB with RF flange, and compliant with API 609 for reliable sealing and durability.
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The double offset high performance butterfly valve, with lever operation and lug body, is designed per API 609. The CF8M body and PTFE seat butterfly valve is more durable in serving the application. Quick Detail Type Butterfly Valve Size 3'' Design Pressure 150LB Construction Double Eccnetric, Soft Seat Connection Type Lug Operation Wrench Operated Design Code API 609 Face to Face ASMEB16.10 End Connection ASMEB16.5 Test & Inspection API 598 Body Material Stainless Steel CF8M Temperature Range -29℃~+150℃ Application Water, Oil, Gas Dimension Class 150 DN mm 40 50 65 80 100 125 150 200 250 300 350 400 NPS in 1 1/2 2 2 1/2 3 4 5 6 8 10 12 14 16 L mm 127 127 127 127 152 203.2 203.2 203.2 203.2 in 5 5 5 5 6 8 8 8 8 L1 mm 38.1 46 50.8 48 54 63.5 57 63.5 71.5 81 92 101.5 in 1.5 1.81 2 1.88 2.13 2.5 2.25 2.5 2.81 3.19 3.62 4 H mm 185 190 220 229 239 252 284 307 337 392 435 481 in 7328 7.48 8.7 9 9.4 9.9 11.2 12 13.3 15.4 17.1 19 D(W) mm 160 160 160 160 160 160 160 200 200 250 250 300 in 6.3 6.3 6.3 6.3 6.3 6.3 6.3 7.9 7.9 9.8 9.8 11.8 Weight (Kg) mm 12.5 13.5 17 38 72 105 148 182 230 in 8 9 10 10 11 14.5 34.2 66 98 134 168 200 Related Knowledge What is a high performance butterfly valve? A high performance butterfly valve is often designed with double offset and PTFE seat, to handle everything from general applications to viscous and corrosive liquids; corrosive gases and steam. Compared to concentric resilient seat butterfly valve, the disc of the high performance butterfly valve is arranged and positioned off the center of the pipe bore, which could reduce wear and tear to the valve during operation and increase sealing performance. In conlusion, high performance butterfly valve is applicable for higher pressure and temperature applications. Meanwhile, it has longer cycle life and better sealing ability.
The high performance butterfly valve is designed with double eccentric or double offset structure. The valve has cast steel WCB body, stainless steel disc and stem along with RPTFE soft seat. Quick Detail Type Butterfly Valve Nominal Size 6 Inch Nominal Pressure Class 150 Structure Double Offset, Double Eccentric, Soft Seat Connection Type Lug Type Operation Gear Operated Design Code API 609 Face to Face ASME B16.10 End Connection ASME 16.5 Test & Inspection API 598 Body Material Cast Steel WCB Trim Material CF8M Disc, 17-4PH Stem, RPTFE Seat Application Water, Oil, Gas Dervos Inspection Report
The 3 inch 150LB butterfly valve has a double-offset disc design that allows the disc to move off the seat reducing running torque and seat wear. The Wafer type valve can be driven by a gearbox and handwheel or by electric, pneumatic or hydraulic actuator.
12" 300LB butterfly valve is made according to API 609 standard. The valve body is made of WCB. It has the structural characteristics of high performance and double eccentric. Its operation is turbine operation and packing is graphite.
DN900 150LB Triple Offset Metal Seated Butterfly Valve is made according to API609 standard. The valve body is made of C95500. It has the structural characteristics of Triple offset, bidirectional equal pressure zero leakage. Its connection mode is FF double flange. And it has Turbine operation mode.
DN200 PN25 Y Type Strainer is made according to BS EN 13709 standard. The valve body is made of EN 10213 1.0619. It has the structural characteristics of Y-shaped, mesh size: 1.6 mm, without drain plug. Its connection mode is RF.
The top entry full port ball valve with drain, vent and sealant injection is designed as per API 6D. The high pressure ball valve has Class 900 raised face flange and gearbox. Quick Detail Type Ball Valve Size 16" Pressure ANSI 900 Construction 1 Piece Body, Top Entry, Bolted Bonnet Connection Flanged End Operation Mode Gearbox Body Material A216 WCB 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 Related Knowledge What is a top entry ball valve and its advantage? A top entry ball valve is the valve which we assemble from the top side. It has a one single piece body. The less thread connection on the valve body means less weight and leakage paths. Plus, we could have access to the ball part without removing it from the pipeline. The top entry ball valves are often used in the pipeline with less maintenance for internal parts. Inspection Reports For each order, Dervos will provide inspection reports to show you the whole inspection process and results. Plus, we will provide material report to let you know that the material we provide is as per standards.
The 12 inch high pressure check valve is designed with pressure seal bonnet, RTJ flange, tilting disc, made of carbon steel WCB body and hard face sealing. Quick Detail Type Check Valve Size 12'' DesignPressure 2500LB Construction Pressure Seal Bonnet, Tilting Disc Type Connection RTJ Flange Design & Manufacture ASME B16.34 End to End ASME B16.10 Connection ASME B16.5 Pressure & Temp ASME B16.34 Test & Inspection API 598 Body Material A216 WCB Trim Material 13CR+STL Temp Range -29℃~+350℃ Media W.O.G. Product Range Body Material Range: WCB, WCC, WC1,CF8M, CF8, CF3, CF3M, LCB, LCC Size Range: 2”~60” (DN50~DN1500) End Connection Type: Flange End, Weld End Design Pressure Range: 150lbs~600lbs Temp Range: -46℃~ +425℃ Related Knowledge What is a tilting disc check valve? The disc of a tilting disc check valve has a pivot point at the center of it. It is desinged to overcome weaknesses of general type swing check valve. Compared to swing type check valve, the tilting check valve could remain fully open and steady at lower flow rates. That is to say, the swing check valve needs a high velocity of fluid to keep disc open and a higher cracking pressure. For low pressure situation, the pressure drop of a tilting disc check valve is much lower than the swing type. But at a higher flow rate, the tilting check valve has higher pressure drop than swing type.
1” 1500LB Forged Steel Ball Check Valve is made according to API 602 ＆ ASME B16.34 standard. The valve body is made of A182 F316. It has the structural characteristics of Hemispherical Ball Check Valve. Its connection mode is BSP.
6"X4" 90LB ball valve is made according to ASME B16.34 standard. The valve body is made of A105. It has the structural characteristics of reduced diameter, fixed ball, DIB-1, fireproof, anti-static, 3-piece. Its connection mode is RTJ. And it has worm wheel operation mode.
The eccentric butterfly valve has triple offset design. It has excellent sealing performance and longer service life due to its small abrasion on sealing face during operation of valve. The 30'' butterfly valve is designed with ANSI 150 double flanged connection and fully metal seat. Quick Detail Type Butterfly Valve Size 30 Inch DesignPressure ANSI 150 Construction Triple Offset/ Triple Eccentric ConnectionType RF Double Flanged Type Operation Gearbox Operation Design Code API 609 Face to Face ASMEB16.10 End Connection ASMEB16.5 Test & Inspection API 598 Body Material A216 WCB TemperatureRange -29℃~+427℃ Application Water, Oil, Gas Available Product Range Norminal Size: 2 Inch ~150 Inch Design Pressure: 150LB~900LB Valve Connection: Flanged, Lug, Wafer, Butt Weld (BW) Valve Operation: :Lever/Wrench, Gearbox, Motorized, Pneumatic Body Material: Carbon Steel WCB, Stainless Steel CF8/CF8M/CF3/CF3M, Low Temperature Steel LCB/LCC Seat Material: Fully metal seat, SS+Graphite Seat
3/4" 800LB Forged Steel Floating Ball Valve is made according to ASME B16.34 standard. The valve body is made of A105. It has the structural characteristics of Full Bore, Floating Ball, Split Body, Side Entry. Its connection mode is FNPT.The valve is operated by LEVER OP..
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