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Check Valve Maintenance: When to Replace and How to Fix Common Issues
Check Valve Maintenance: When to Replace and How to Fix Common Issues
2025-11-06

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 ...

What Are the Differences Between Flanged Globe Valves and Threaded Globe Valves?
What Are the Differences Between Flanged Globe Valves and Threaded Globe Valves?
2025-10-31

If you’ve ever hesitated between choosing a flanged or threaded globe valve, you’re not alone. Globe valves are common shut-off valves widely used in industries such as oil and gas, chemical processing, power generation, shipbuilding, and water treatment. While both connection types can control fluid flow, they differ significantly in terms of installation method, sealing performance, and suitable applications. This article will provide a systematic comparison of flanged and threaded globe valves from the perspectives of structure, performance, and application.   I. Fundamental Difference in Connection Methods   1.Flanged Globe Valve A flanged globe valve connects to the pipeline through flanges, with bolts tightening the flange faces together to ensure a secure seal.This connection type offers excellent strength and reliability, making it ideal for medium to high-pressure, large-diameter, and frequently operated systems.In industrial applications, typical sizes range from DN50 to DN300, and flange dimensions generally follow international standards such as ANSI, DIN, or JIS.   2. Threaded Globe ValveA threaded globe valve typically uses either internal (NPT/BSP) or external threads to connect to the pipeline, relying on the threads themselves for sealing.This compact and lightweight structure allows for easy installation and is mainly used in small-diameter (usually ≤ DN50) and low-pressure systems, including residential pipelines.Because it does not require welding or flange gaskets, a threaded valve is more cost-effective in both installation and maintenance.     II. Comparison of Sealing Performance and Maintenance   Flanged Globe ValveFlanged globe valves typically use metal or flexible graphite gaskets for sealing, offering excellent resistance to high temperature, high pressure, and corrosion.During long-term operation, maintenance or valve replacement is straightforward—simply loosen the flange bolts to disassemble the valve.   Threaded Globe ValveThe sealing of a threaded globe valve mainly depends on the thread engagement and sealing materials such as PTFE tape or sealing paste.However, repeated disassembly can damage the threads and increase the risk of leakage.For this reason, threaded globe valves are better suited for fixed installations, clean fluids, and low-pressure systems.     III. Structural Dimensions and Installation Requirements   Flanged Globe ValveFlanged globe valves are larger in size and require more installation space, but they provide superior vibration resistance and pressure tolerance.They are commonly used in industrial piping networks or pump station systems where sufficient structural support is available.   Threaded Globe ValveThreaded globe valves feature a compact design, making them ideal for confined spaces or lightweight piping systems such as laboratories, compressor inlets and outlets, and domestic water supply lines.However, thr...

Valve Market 2025: Smart Upgrades and Infrastructure Investment Drive Global Growth
Valve Market 2025: Smart Upgrades and Infrastructure Investment Drive Global Growth
2025-10-24

The global industrial valve market is undergoing a quiet yet significant transformation. Growth is no longer driven mainly by new construction projects — instead, it’s increasingly fueled by the replacement and modernization of aging equipment and infrastructure. From petrochemical plants to municipal water systems and natural gas pipelines, valve upgrades have become a key priority across industries.   Aging Equipment Drives Rising Valve Replacement Demand   In many industrial facilities, valves—though seemingly durable—gradually suffer from seal wear, sluggish operation, and leakage after years of service. For plants operating over a decade, valve degradation has become a major factor affecting safety and efficiency.   With stronger focus on maintenance, process safety, and energy efficiency, end users in oil & gas, power, and water treatment sectors are accelerating valve replacement and upgrade projects. This trend aligns with a global shift toward predictive maintenance and sustainable operations, increasing demand for ball valves, gate valves, and control valves.   Market research from Mordor Intelligence and others shows a shorter valve replacement cycle due to rising maintenance costs and downtime risks. Stricter environmental and safety standards are also pushing faster modernization worldwide. In the U.S., for example, the water sector—with pipelines averaging over 40 years old—is investing in large-scale valve renewal programs to reduce leakage and unplanned shutdowns. Similar initiatives are emerging across Europe and Asia.   Infrastructure Investment Fuels Market Expansion   Beyond replacements, ongoing infrastructure investment continues to drive valve demand globally. Asia’s rapid industrial growth and the Middle East’s refining and petrochemical expansion have led to increased valve procurement.   According to GMI Insights, the global industrial valve market reached USD 75.9 billion in 2024 and is projected to hit USD 142.6 billion by 2034 (CAGR: 6.6%). Precedence Research forecasts even higher potential—up to 12.5% CAGR.   This growth is backed by large-scale upgrades in urban water networks, wastewater treatment plants, natural gas pipelines, and energy transition projects such as hydrogen and carbon capture systems, all requiring next-generation high-performance valves.   Valve Replacement Becomes a Smart Technology Upgrade   Modern valves are evolving beyond mechanical parts. With smart manufacturing and the Industrial Internet of Things (IIoT), today’s valves feature sensors, smart actuators, and remote monitoring. Engineers can now track performance in real time and conduct predictive maintenance, reducing unexpected downtime.   Advanced materials like corrosion-resistant alloys, cryogenic steels, and special polymers are extending service life and reliability—especially in harsh environments. For indu...

Cast Iron Non Rising Stem Gate Valve
加载中...

Cast Iron Non Rising Stem Gate Valve RF DN80 PN16

  • 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:

    Cast Iron Gate Valve, Grey Iron Gate Valve
  • Method of Operation:

    Handwheel Operated Gate Valve
Inquiry now
Product Detail

The DN80 PN16 cast iron gate valve has face to face dimension as per DIN3202 F4 or DIN3202 F5. This GG25 gate valve is designed with resilient seat, non rising stem, bb, RF flange, suitable for water treatment application.


Quick Detail

Type

Gate Valve

Nominal Diameter

DN 80

Nominal Pressure

PN 16

ConstructionType

Non-rising stem, Bolted Bonnet, Resilient Seat

ConnectionType

Flanged

OperationType

Handwheel Operation

Body Material

Cast Iron GG25

TrimMaterial

Cast Iron Wedge, SS420 Stem, EPDM Seat

Design Code

DIN 3352

End to End Code

DIN 3202

Flange Dimesion

DIN 2501

Medium

Water

Origin

China


Design Feature
1.Resilient seat for good sealing performance
2.Low flow resistance and small pressure drop
3.Non-rising stem for installation space is limited
4.No limitation for flow direction of medium
5.Epoxy painting available for internal and external part of the valve for anti corrosive function

Company Brief Introduction
Specializing in valve industry over 10 years, Dervos becomes the leading vendor of gate, globe, check, ball, butterfly, plug valves and strainers. We serve oil and gas user such as LUKOIL, MOL, YPF with local partners.


Dervos show its advantages in:
1. Our partnerships with tens of stable suppliers allow us to provide customers with a wide range of high-quality products at a competitive price.
2. Each order is under strict quality control with inspection reports before delivery.
3. We value delivery time as much as our customers do. With the powerful purchasing system, we follow each order closely to secure on-time delivery.
4. One-stop solutions will be offered in a timely manner

Cast Iron Gate Valve Manufacturers


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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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