Recently, representatives from Dervos Valve visited long-term industrial valve partners in Norway, Italy, Germany, and Spain. The multi-day trip focused on understanding customers’ current project requirements and discussing future procurement plans and technical specifications in greater depth. In Norway, our team was invited to visit the customer’s equipment installation workshop and valve application site. Through direct discussions with the engineering and procurement teams, we gained a clear understanding of their concerns regarding high-pressure applications, material selection, and delivery schedules. The customer noted, “Dervos has an excellent grasp of our project needs. Your quick response and professional recommendations give us great confidence.” This feedback reflects not only trust in our product quality but also strong recognition of our service capabilities. The team then traveled to Italy for technical discussions with our local partners and visited their valve assembly and testing facilities. Our representatives introduced Dervos’s manufacturing capabilities, quality inspection processes, and ongoing product enhancements across ball valves, gate valves, butterfly valves, and check valves. The Italian customer remarked, “The solutions you presented are highly practical and will significantly improve the reliability of our projects.” Such positive feedback further strengthened the confidence in our partnership. Through this trip, Dervos gained deeper insights into the European market’s expectations regarding valve performance, quality control, and delivery reliability. We will continue to refine our products and services based on customer feedback, ensuring that every partner receives a reliable and fully tailored one-stop valve solution. Looking ahead, Dervos Valve will remain committed to our service philosophy of listening to customers, responding quickly, and delivering real value. With higher product standards and more professional technical support, we aim to strengthen and advance our cooperation with customers around the world.
Butterfly valves are widely used as regulating and shut-off devices in industrial piping systems, valued for their simple structure, lightweight design, and rapid open-close operation. They find applications across water treatment, chemical, metallurgical, power, oil, and gas industries. However, even high-quality butterfly valves can experience performance degradation if proper maintenance is neglected over long-term operation.This article explores the structural features, common issues, and maintenance practices to help effectively extend the service life of butterfly valves. 1. Understanding the Operational Characteristics of Butterfly Valves A butterfly valve primarily consists of a valve body, disc, stem, sealing elements, and an actuator. Its operation relies on the rotation of the disc, driven by the stem, to control fluid flow. During operation, the disc remains immersed in the fluid, subject to erosion, corrosion, and pressure shocks. Therefore, the valve’s lifespan is closely related to sealing performance, material selection, and the operating environment. 2. Common Factors Affecting Butterfly Valve Lifespan Frequent Operation and High Differential Pressure High-frequency cycling or prolonged operation under high pressure and flow velocity can cause valve seat wear and stem seal aging. Corrosive Media and Sediment Build-Up Chemical fluids or particulate-laden media can corrode the disc and clog sealing surfaces, reducing smooth operation. Improper Installation Misalignment between the valve and pipeline, or uneven bolt tightening, may lead to eccentric disc friction and damage to sealing elements. Lack of Regular Maintenance Neglecting routine cleaning and lubrication can increase operating torque, accelerate seal wear, and shorten the valve’s overall service life. 3. Maintenance Tips to Extend Butterfly Valve Lifespan 1. Proper Installation as the Foundation Ensure the valve body is aligned with the pipeline center to avoid eccentric stress. Use appropriate gaskets between the valve and flange to prevent localized stress. For actuated butterfly valves, confirm correct travel adjustment to avoid exceeding torque limits. 2. Regular Cleaning and Inspection Periodically remove deposits and debris from the disc surface to prevent seal surface damage. Check stem packing and seals; replace immediately if signs of aging are detected. For pipelines carrying particulate-laden media, flush the valve regularly to prevent clogging. 3. Lubrication and Corrosion Protection Apply grease to the stem, bearings, and drive components regularly to maintain smooth operation. For valves operating in seawater or corrosive environments, select corrosion-resistant coatings or materials such as aluminum bronze or duplex stainless steel. 4. Proper Operation and Control Avoid rapid or forced operation to prevent disc deformation from impact. If the ...
A check valve is a critical device that prevents backflow, widely used in water treatment, oil & gas pipelines, chemical processing, and steam systems. After long-term operation, check valves may experience issues such as leakage, vibration noise, or sticking. If not addressed promptly, these problems can reduce system efficiency and even cause equipment damage or safety hazards. So, how can you tell if a check valve needs replacement? Which faults can be repaired, and which require a full replacement? This article provides a systematic guide. 1. Basic Operating Principle of Check Valves The primary function of a check valve is to automatically prevent backflow. When fluid flows in the intended direction, the valve disc is pushed open by pressure; when flow reverses, the disc closes automatically, using either its own weight or a spring, preventing backflow. Common types include: Lift Check Valve Swing Check Valve Dual Plate Wafer Check Valve Ball Check Valve Although their designs vary, the key criteria for determining whether a check valve needs replacement remain the same: sealing performance, operational smoothness, and structural integrity. 2. How to Determine if a Check Valve Needs Replacement Visible Leakage (Internal or External) If fluid continues to flow backward when the valve is closed, it indicates significant wear or deformation of the sealing surfaces, preventing an effective seal. If the leakage exceeds system tolerances and cannot be corrected by cleaning or resurfacing, the valve or its sealing components should be replaced. Sticking or Inflexible Valve Disc After long-term operation, the valve stem, guides, or disc may become stuck due to scaling, corrosion, or debris. If cleaning, descaling, or lubrication fails to restore smooth operation, replacement is recommended. Excessive Noise or Vibration Frequent opening and closing or rapid disc rebound can cause vibration or knocking sounds. This is usually due to spring failure, loose valve components, or worn guides. Persistent or frequent noise should trigger inspection of the valve’s structural integrity and consideration for replacement. Corroded or Cracked Valve Body or Cover Exposure to acidic, alkaline, or high-temperature fluids can corrode or crack the valve body, compromising structural strength and posing safety risks. Such damage cannot be repaired and requires full valve replacement. Frequent Backflow or Abnormal System Pressure Fluctuations Poor sealing or delayed valve response can cause system pressure variations, including water hammer. If repeated adjustments do not resolve the issue, it indicates aging of the internal spring or disc mechanism, necessitating timely replacement. 3. Common Fault Diagnosis and Solutions Fault: Valve fails to close completely, causing backflow Cause: Worn sealing surfaces, deformed disc, or trapped debris Solution: Remove ...
DN250 PN10 check valve body is made of A216 WCB+STL. It has the structural characteristics of heavy hammer on both sides and flange type. Its connection mode is RF.
Payment:
30% when order confirmed, 70% before shipmentProduct Origin:
ChinaColor:
CustomizationShipping Port:
Shanghai, ChinaLead Time:
30~60 days Ex Works after order confirmationMaterial:
A216 WCB+STLProduct Description
|
Type |
Check Valve |
|
Size |
DN250 |
|
Pressure |
PN10 |
|
Connection |
RF |
|
Body Material |
A216 WCB+STL |
|
Face to Face Dimensions |
E558-1 SER.14 |
|
End Flange Dimensions |
EN1092-1 |
|
Test & Inspection Code |
API 598 |
|
Applicable Medium |
Water, Oil and Gas |
Features
1. The valve seat design is inclined, with short closing stroke and time, avoiding damage caused by water hammer;
2. It prevents fluid backflow on horizontal or vertical pipelines.
Technical Drawing
Dimension Checking
Pressure Testing
Painting
Nameplate & Packing
Inspection report
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 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.
10" 150LB tilting disc check valve is made according to API 6D standard. The valve body is made of A216 WCB+SS316. It has the structural characteristics of swash plate type. Its connection mode is wafer.
3" 150LB tilting disc check valve is made according to API 6D & BS1868 standard. The valve body is made of ASTM A351 CF8M. It has the structural characteristics of tilting disc type, bolt cover. Its connection mode is RF.
6" 150LB gate valve is made according to API600 standard. The valve body is made of ASTM A216 WCB. It has the structural characteristics of bolt cover, rising stem and elastic wedge. Its connection mode is RF. And it has hand wheel operation mode.
EN 13709 Design and manufacture. EN558-1 Face to Face dimension. EN1092-B1 Flange and dimension. EN12266 Test and inspection standard.
The 6 Inch PSB globe valve has 1500LB design pressure, butt weld end, and gearbox. The full bore globe valve is made of carbon steel WCB body and trim 5 material. Quick Detail Type Globe Valve Size 6'' Design Pressure Class 1500 Construction Pressure Seal Bonnet, Plug Type Disc, Rising Stem Connection Type Butt Weld Operation Type Bevel Gearbox Opearted Design Code BS 1873 End to End ASME B16.10 Connection End ASME B16.25 Pressure & Temperature ASME B16.34 Test & Inspection Standard API 598 Body Material Cast Steel WCB Trim Material Trim NO. 5 Temperature Range -29℃~+425℃ Application WOG Origin China Material & Dimension NPS DN Class 2 2 1/2 3 4 6 8 50 65 80 100 150 200 L(RF) L1(BW) 900LB 368 419 381 457 610 737 1500LB 368 419 470 546 705 832 2500LB 451 508 578 673 917 1022 L2(RTJ) 900LB 371 422 384 460 613 740 1500LB 371 422 473 549 711 841 2500LB 454 514 584 683 927 1038 H(Opne) 900LB 550 605 678 798 930 1230 1500LB 550 605 866 956 1260 1263 2500LB 560 720 755 1230 1791 2086 W 900LB 350 350 400 450 458 610* 1500LB 400 400 450 560 610* 610* 2500LB 400 450 560 310* 610* 760 Weight (RF) 900LB 78 108 102 142 400 960 1500LB 85 110 135 230 660 1590 2500LB 140 168 247 620 1500 3200 Weight (BW) 900LB 66 91 87 128 355 868 1500LB 77 101 122 209 595 1440 2500LB 100 118 180 438 1148 2594 *Manual gear operator is recommended No Part Name Carbon steel to ASTM Alloy steel to ASTM Stainless steel to ASTM WCB WC6 WC9 C5 CF8 CF8M CF3 CF3M 1 Body A216 WCB A217 WC6 A217 WC9 A217 C5 A351 CF8 A351 CF8M A351 CF3 A351 CF3M 2 Seat Ring A105 A182 F11 A182 F22 A182 F5 A182 F304 A182 F316 A182 F304L A182 F316L 3 Disc A105 A182 F11 A182 F22 A182 F5 A182 F304 A182 F316 A182 F304L A182 F316L 4 Stem A182 F6 A182 F304 A182 F304 A182 F316 A182 F304L A182 F316L 5 Disc nut A182 F6 A182 F304 A182 F304 A182 F316 A182 F304L A182 F316L 6 Cap SS Spiral Wound graphite or SS Spiral Wound PTFE 7 Body Seal Flexible Graphite+316 8 Adjustment Gasket F6 F6 F316 9 Stem packing Flexible Graphite+316 10 Gland Nut A194 2H A194 8 11 Gland Eyebolt A193 B7 A193 B8 12 Pin Carbon steel or Stainless Steel 13 Cap Nut Carbon steel or Stainless Steel 14 Gland A182 F6 A182 F304 A182 F316 A182 F304L A182 F316L 15 Gland Flange A216 WCB A351 CF8 16 Yoke A216 WCB A351 CF8 17 Stem Nut A439 D2 or B148-952A 18 Screw Carbon steel 19 Handwheel Ductile Iron or carbon steel 20 Name Plate Stainless steel or Aluminum 21 Washer Carbon steel 22 Nut Carbon steel or Stainless Steel Related Knowledge Why do we use pressure seal bonnet? Pressure sealed bonnet are often used for valves with high design pressure. The higher the internal pressure gets, the greater the sealing force beween body and bonnet become. For bolted bonnet valves, the body and bonnet are joined by studs and nuts with a gasket between the flange faces to facilitate sealing. However,as system pressure increases,the potential for leakage through the body and bonnet increases. But for pressure sealed valve, “bonnet take-up bolts” to pull the bonnet up and seal against the pressure seal gasket. That is why when pressure increase, the performance of pressure seal gasket between body and bonnet becomes better.
The 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
Line blind valve is a kind of gate valve that cuts off gas medium manually, electrically or pneumatically or hydraulically. It is generally divided into electric blind valve, hydraulic blind valve, closed plug valve and electric open blind valve.
Y type globe valve. CF8 body/bonnet, F304 disc/stem, SS304+flexible graphite gasket and bronze bolt and nut. Plug type disc and Raised face flange connection. Quick Detail Type Globe Valve Size 4 inch DesignPressure CL150 Construction Y Type Globe Valve Connection Type Raised Face Flange Connection Operation Handwheel Design Code ASME B16.34 Face to Face ASME B16.10 Test & Inspection API 598 Body Material CF8 Temperature Range -29~538℃ Application WOG
12" 600LB Trunnion Mounted Ball valve is made according to API 6D standard. The valve body is made of ASTM A216 WCB. It has the structural characteristics of 2-piece, side mounted, fixed ball, full bore, fire-resistant API6FA, anti-static, valve stem anti blow-out. Its connection mode is RF. And it has Worm Gear operation mode.
The double- disc check valve, made of CF8 stainless steel, has excellent resistance to corrosion. Designed in accordance with DIN 3202, the check valve is about to connect to pipes with WAFER. Quick Detail Type Check Valve Nominal Diameter DN100 NominalPressure PN25 Construction Double disc/ Dual Plate Connection Wafer Type Design & Manufacture DIN 3202 End to End DIN 3202 Flange End Dimension DIN 2401 Test & Inspection API 598 Temperature Range -29℃~+425℃ Body Material A351 CF8 Wedge Material A351 CF8 Media W.O.G. Dervos Packaging Good packing means good first impression. Just imagine how do you feel differently when seeing two boxes below? And you will know the reason why in Dervos we value packaging so much. In Dervos, we make sure- 1. Every valve isclean and dry. What do we do? -Clean the valve before packing -Add anti-rust oil -Add flange cover 2. No damageto valves in delivery. How do we achieve this? -Fix the valve with iron wire -Separate the valve with soft material -Layer the valve with plywood 3. Strong box and clear shipping mark
Copyright © 2015-2025 DERVOS VALVE CO.,LTD.All Rights Reserved Blog / Sitemap / XML / Privacy Policy
