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Three Common Causes of Valve Leakage and Emergency Remedies
Three Common Causes of Valve Leakage and Emergency Remedies
2025-05-28

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...

Can Oil Pass Through a Strainer? How Pre-Filtration Works in Lubrication Systems
Can Oil Pass Through a Strainer? How Pre-Filtration Works in Lubrication Systems
2025-05-20

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...

Are Ball Valves Suitable for Water Systems? A Practical Guide for Engineers & Installers
Are Ball Valves Suitable for Water Systems? A Practical Guide for Engineers & Installers
2025-04-30

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...

Cast Steel Pressure Balanced Plug Valve
加载中...

Lubricated Plug Valve Pressure Balanced Type 8 Inch

  • Payment:

    30% T/T When Order, 70% T/T Before Shipment
  • Product Origin:

    China
  • Color:

    Customization
  • Shipping Port:

    Shanghai China
  • Lead Time:

    35~60 days Ex Works After Order Confirmation
  • Material:

    Carbon Steel Plug Valve, Cast Steel Plug Valve, WCC
  • Method of Operation:

    Gear Operated Plug Valve
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Product Detail
The 8 inch lubricated plug valve features in inverted and pressure balanced type structure. The flanged metal seated plug valve is suited for natural gas application.

Quick Detail

Type

Plug Valve

Size

8''

Design Pressure

300LB

Construction

Lubricated Type, Inverted Type, Pressure Balanced Type, Metal Seated

Connection Type

Flanged Connection

Operation

Gear Operated

Design Code

API 599

Face to Face

ASME B16.10

End Connection

ASME B16.5

Pressure & Temp

ASME B16.34

Test & Inspection

API 598

Body Material

WCC

Temperature Range

-29℃~+425℃

Application

Water, Oil, Gas


Dimension


Lubricated Plug Valves Manufacturers
Class Size 1 1/2 2 2 1/2 3 4 6 8 10 12
300 B 191 216 241 283 305 403 419 457 502
C 156 165 191 210 254 318 381 445 521
D 20.6 22.2 25.4 28.3 31.8 36.5 41.3 47.6 50.8
E 169 178 219 235 362
F 106 118 143 165 187 248 300 392
O 73 92.1 105 127 157 216 270 324 381
Weight(RF) 16 21 38 60 101 192 281 508


Related Knowledge

What is a plug valve?


Plug valve is a quater-turn valve whose plug rotates around the centerline of valve body to realize on-off function. The plug valve is used for cutting off, distributing and changing the flow directoin. Currently, plug valves are mainly applicable for small size, normal temperature, and low pressure conditions.


The advantages of plug valve are shown below:
-Quick opening and closing the valve
-Small fluid resistance
-Reliable leak-tight service
-Available inline maintenance 


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    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.

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