In industrial production, valves are critical components for fluid control, and their sealing performance directly impacts system safety and stability. Leakage not only reduces operational efficiency but may also lead to fluid escape, posing serious safety risks. This article outlines three common causes of valve leakage and provides corresponding emergency response recommendations to help you quickly identify issues, take action, and mitigate risks. 1. Seal Surface Wear or Damage Cause: During long-term operation, sealing pairs (e.g., valve seat and disc, valve ball and seat) suffer from media erosion, particle abrasion, or corrosion, leading to uneven sealing surfaces and resulting in minor or significant leakage. Emergency Measures: · Minor Leakage: Adjust compression force (e.g., tighten bonnet bolts) to temporarily reduce leakage. · Severe Leakage: Immediately shut down the system to replace or regrind sealing components; replace the entire valve if necessary. Prevention Recommendations: Conduct regular inspections, select valves with appropriate materials and wear-resistant designs. For media containing solid particles, use hard-sealing structures. 2. Packing Aging or Gland Loosening Cause: Valve stem sealing uses packing materials (e.g., graphite, PTFE), which may age, dry, or crack over prolonged use. Temperature fluctuations can also cause gland loosening, leading to leakage at the packing box. Emergency Measures: · Tighten packing gland bolts to increase packing compression. · If ineffective, add or replace packing material. · Avoid over-tightening to prevent increased operating torque or stem damage. Prevention Recommendations: Regularly replace packing; select materials compatible with the media and operating temperature. For critical equipment, consider spring-loaded packing glands. 3. Casting Defects or Corrosion Perforation in Valve Body/Bonnet Cause: Some low-quality valves have casting defects such as sand holes or shrinkage cavities. Prolonged exposure to corrosive media can cause localized perforation of the valve body, resulting in uncontrollable leakage. Emergency Measures: · For small leaks, temporary repairs using metal adhesives or cold welding are possible. · Large-scale damage requires immediate valve replacement. · For high-pressure or toxic/hazardous media, no pressurized repair is allowed; follow shutdown procedures strictly. Prevention Recommendations: Purchase valves from reputable manufacturers; use corrosion-resistant materials (e.g., 304/316L stainless steel). Perform regular wall thickness inspections on critical pipelines. Common Questions & Answers (Q&A) Q1: Can all valve leaks be fixed by replacing packing?A: No. Packing replacement is effective only when leakage is due to packing aging or gland loosening. If the leakage stems from seal surface or valve body damage, other me...
In any efficient and reliable lubrication system, oil cleanliness is a core factor affecting equipment lifespan and operational efficiency. Strainers, as the front-line filtration devices in lubrication systems, play a critical role in pre-filtration. However, engineers and operators often raise the following questions: Can oil pass through strainers smoothly? What exactly is the function of a strainer? How does it differ from subsequent fine filters? This article systematically explains the role of strainers in lubrication systems, covering their working principles, pre-filtration objectives, and practical applications across different systems. 1. Can Oil Pass Through a Strainer? Answer: Yes, but with limitations. (1) Strainer Structure Allows Oil Flow A strainer is fundamentally a low-precision filter made of stainless steel mesh or perforated metal plates. It features uniform pores, typically sized between 80–500 μm (micrometers), allowing most clean oil to flow through unimpeded. (2) Contaminants Are Blocked Particles such as metal shavings, seal fragments, and carbon deposits in the oil are intercepted by the strainer, preventing them from entering the oil pump or other critical components. (3) Oil Temperature and Viscosity Affect Flow Efficiency Low temperatures or high-viscosity oil may reduce flow rates or even cause blockages. This is one reason for low oil pressure during system startup. 2. Objectives and Significance of Pre-Filtration (1) Protecting the Oil Pump Internal pump components (gears, impellers, or plungers) are highly sensitive to solid particles. Pre-filtration prevents particles from entering the pump, avoiding premature wear or seizure. (2) Reducing Load on Primary Filters By intercepting large contaminants, strainers allow primary filters (e.g., oil filter cartridges) to focus on finer impurities, extending their service life and maintaining stable system flow. (3) Lowering System Failure Rates Pre-filtration reduces risks such as pump failure, orifice blockages, and lubrication breakdown caused by foreign particles, enhancing overall system reliability. 3. Typical Applications of Pre-Filtration Devices Application System Strainer Installation Position Strainer Type Internal Combustion Engine Lubrication Oil sump → Pump inlet Coarse metal strainer Hydraulic Systems Tank outlet → Pump suction port Suction strainer or basket strainer Turbine Lubrication Systems Pump inlet Dual-chamber switchable suction strainer Transmission/Clutch Systems Oil sump → Circulation pump inlet Perforated plate + magnetic strainer 4. Design and Usage Considerations for Strainers (1) Pore Size Selection Must Align with System Precision Requirements 80–100 μm: Typical for engine oil systems. 150–300 μm: Used in hydraulic equipment. >400 μm: Suitable for low-pressure or open-loop systems. (2...
Ball valves, with their simple structure, easy operation, and excellent sealing performance, have become widely used control components in both industrial and residential sectors. Particularly in water supply systems, an increasing number of engineers and installers are choosing ball valves as the primary fluid control device. But are ball valves truly suitable for water systems? How should one properly select and install them to ensure long-term stable operation? This article provides a comprehensive overview from the perspectives of structural principles, performance characteristics, and application recommendations. 1. Advantages of Ball Valves in Water Systems (1) Quick Opening and Closing Ball valves can complete the opening and closing operation with a simple 90° rotation, making them easy to operate and highly responsive—ideal for emergency situations or water systems that require frequent switching. (2) Excellent Sealing Performance High-quality ball valves are equipped with PTFE or reinforced sealing materials, enabling zero leakage. They are particularly suitable for water supply systems in residential buildings, commercial complexes, and industrial facilities where sealing performance is critical. (3) Compact Structure and Space-Saving Compared to gate valves or globe valves, ball valves occupy less space and offer flexible installation, making them ideal for water modules with high equipment integration. (4) Strong Corrosion Resistance Ball valves made of stainless steel, brass, or plastic materials (such as UPVC) offer excellent corrosion resistance, capable of handling various water qualities (soft water, hard water, reclaimed water) and different additives. 2. Application Scenarios Analysis Ball valves are suitable for the following types of water systems: (1) Domestic Water Systems: Such as internal building water supply, point-of-use control for sanitary fixtures, and garden irrigation systems. (2) Industrial Water Systems: Such as cooling water circulation systems, boiler feedwater systems, and water supply for cleaning equipment. (3) Water Treatment Systems: Including reverse osmosis pretreatment, greywater recycling, and wastewater transfer processes. (4) Special Applications: High-pressure hot water systems or cleaning water containing chemical additives. However, caution should be exercised in the following scenarios: (1) High-Frequency Modulation Conditions Standard ball valves are not suitable for precise flow regulation. It is recommended to use V-port ball valves or control-type electric ball valves. (2) Water Containing Sand, Gravel, or High Levels of Suspended Solids A Y-strainer should be installed to prevent particle blockage or damage to the sealing surfaces. (3) High-Temperature Hot Water Systems High-temperature ball valves with metal sealing structures should be selected to prevent seal aging and deformation. 3. Key Selection Criteria To ensure stable operation o...
The 8 inch top entry ball valve with features of cavity pressure self-relief and emergency sealant injection is designed as per API 6D. It’s capable to handle working pressure up to 900LB.
Payment:
30% when order confirmed, 70% before shipmentProduct Origin:
ChinaColor:
CustomizationShipping Port:
Shanghai, ChinaLead Time:
30~60 days Ex Works after order confirmationMaterial:
ASTM A105.Method of Operation:
Bare StemQuick Details
|
Type |
Ball Valve |
|
Nominal Diameter |
2"~60" (DN50~DN1500). |
|
NominalPressure |
150 lbs~2500 lbs (PN16~PN420). |
|
Construction |
Top Entry,One Piece Type |
|
Connection |
BW,RTJ |
|
Operation |
Gearbox, Electric, Pneumatic, Elector Hydraulic Actuator, Gas Over Oil Actuator. |
|
Body Material |
ASTM A105. |
|
Design Code |
API 6D. |
|
Pressure & Temp |
ASME B16.34 |
|
End toEnd Dimension |
ASME B16.10 |
|
Inspection |
API598 |
|
Temperature Range |
-46℃~+200℃. |
|
Media |
Oil, Water, Gas |
Dervos top entry ball valves are engineered to meet international standards of API 6D, ASME B16.34 and others on request. The range contains both soft , metal or composite seats that can be configured to provide an effective double block and bleed (DB&B) .
Features
·Soft, metal or composite material seated
·Bi-directional tight shut-off
·Double block & bleed
·Fire safe and fire tested
·Low operating torque design
·Wide range of materials and sizes
·Anti-blowout stem design
·Suitable for above ground or below ground installation
·Top-entry design enable maintenance in line
·Forged or cast body optional
·Extended Bonnet
Reports
Along with each order, Dervos will provide inspection reports and material test reports free of charge after shipment. All these certificates will let you have a clear picture of inspection process and results. Plus, these reports can be used for traceability.
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 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.
12" 1500LB top entry ball valve is made according to API 6D standard. The valve body is made of ASTM A216 WCB. It has the structural characteristics of top mounted, fixed ball, full bore, fire-safe design and anti-static, blowout-proof stem, inner diameter: 295mm. Its connection mode is RTJ. And it has turbine operation mode.
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-pressure Class 4500 gate valve is designed with PSB and SW end connection. Made of CS A105, the 2 inch gate valve follows the inspection standard API 598 and design standard API 602. Dervos could offer customizing service by providing clients with valves in different sizes, materials, standards, design pressure, structure, operation type and connection type.
6" 150LB strainer is made according to ASME B16.34 standard. The valve body is made of ASTM A216 WCB. It has the structural characteristics of basket type. Its connection mode is RF.
The cast steel lift non return check valve is designed with piston type disc, bolted bonnet, and PN16 RF flange. The spring loaded check valve conforms to DIN 3356. Quick Detail Type Check Valve ( Non-return Valve) Nominal Diameter DN 150 NominalPressure PN 16 Construction Lift Type / Piston Type, Bolted Bonnet Connection Flanged Connection Design & Manufacture DIN 3356 End to End EN 558 Connection EN 1092 Test & Inspection EN 12266 Body Material Carbon Steel GS C25 Media W.O.G. Product Range Body material: CS, SS, Alloy Steel, CI, Bronze, Brass Size Range: 2”~12” (DN50~DN300) End Type: Butt Weld, Socket Weld, Flanged, Screwed Pressure Range: 150lbs~2500lbs (PN16~PN420) Temperature Range: -46℃~ +425℃ Related Knowledge What is a piston check valve? Usually, we have swing type check valve and lift type check valve. A piston check valve and ball check valve both belong to lift type check valve. In a lot of cases, a piston check valve use spring to retain the disc in closed position. The structure of a piston check valve is very similar to the globe valve just without manual operation. Due to its piston type disc and superior leak tight characteristic, the piston check valves are suitable for small size and high pressure conditions.
The valves are widely used in electric power, petroleum chemical industry, metallurgy, Marine, oil, natural gas, coal gas, pharmaceutical and other industries.
6" 150LB gate valve is made according to API 600 standard. The valve body is made of ASTM A217 WC6. It has the structural characteristics of bolt cover, elastic gate, rising stem, OS&Y, full bore, body valve seat. Its connection mode is RF (125~250AARH）. And it has hand wheel operation mode.
The 12 inch 150 LB triple eccentric butterfly valve is designed per API 609 with flange end and gearbox operation. The valve is made of stainless steel CF8 with metal seat design. Quick Detail Type Butterfly valve Size 12 Inch Pressure 150LB Construction Triple Offset/Eccentric, Metal Seat Connection Type Flange Operation Gearbox Design Code API 609 Face to Face ANSI B16.10 End Connection ANSI B16.5 Test & Inspection API 598 Body Material CF8 Applicable Temp -196℃~+800℃ Application Water, Oil, Gas Materials Dimension
DN25 PN100 ball valve is made according to ISO 17292 standard. The valve body is made of ASTM A105. It has the structural characteristics of floating ball, full bore, anti-fire, anti-static, and anti-flying valve stem. Its connection mode is EN1092-1 D. And it has lever 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
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