English

English

Get a Quote
Products

Hot Products

Company News

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...

Globe Valv
加载中...

Bellow Seal Globe Valve 1.5 Inch 150LB Forged Steel

  • Product Origin:

    China
  • Color:

    Customization
  • Shipping Port:

    Ningbo/Shanghai,China
  • Lead Time:

    30~55 days Ex Works After Order Confirmation
  • Material:

    ASTM A105
  • Method of Operation:

    Handwheel
Inquiry now
Product Detail

The bellows seal globe valve adopts the bellows seal design, which completely eliminates the shortcomings of the normal valve stem packing seal aging and easy to leak, not only improves the energy efficiency, increases the safety of the production equipment, reduces the maintenance cost and frequent maintenance. It also provides a clean and safe working environment.Its simple structure and the low price makes it almost no "competitors". 


Quick Detail

Type

Globe Valve

Norminal Size

1.5 Inch

NorminalPressure

150LB

Construction

Bolted Bonnet, Outside Screw & Yoke, Rising Stem, Bellow Seal

ConnectionType

RF Flange

Operation

Handwheel

Design Code

ASME B16.34, API 602

Face to Face

ASME B16.10

Flange End

ASME B16.5

Test & Inspection

API 598

Body Material

ASTM A105

ApplicableTemp

-29℃~+425℃

Application

Water, Oil, Gas


Structure Feature

1. Double seal design (corrugated pipe + packing). If the bellows fails, the stem packing will also be avoided;
2. External leakage, and in line with international sealing standards;
3. No fluid loss, reduce energy loss, and improve plant equipment safety;
4. Long service life, reduce the number of maintenance, reduce operating costs;
5. Rugged bellows seal design, ensuring zero leakage of the valve stem, providing maintenance-free conditions.


Technical Drawing

Dimension


Our Service

Dervos customer service is one of our biggest competitive advantages. In Dervos, we provide-

 

1.Quotation within 24 hours or no later than 3 days

This will let you meet the quotation submission deadline and enhance your working efficiency

 

2.Weekly status report of your order

In this way, you will have a clear picture of your order. You do not need to waste time on pushing us for status update

 

3.An 18-month warranty period

A warranty certificate will issued after shipment and you will not have any concern after buying valves.

 

4.Solutions to complaints within 3 days

Quick and responsible actions to complaints will protect your reputation and reduce the financial loss as much as possible.


Leave A Message

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.

Related Products
Bellow Seal Globe Valve With Handwheel
Bellow Seal Globe Valve 1.5 Inch SW A105N OS&Y

The 1.5 inch 800LB bellow seal globe valve is designed with outside screw and yoke, handwheel operation, sw end. The reduced port globe valve is has forged steel A105N body. Design Feature 1.Outside screw and yoke 2.Rising stem 3.Bolted bonnet design 4.Bellow seal packing for reliable stem sealing 5.Reduced bore design 6.Handwheel Operated Quick Detail Type Globe Valve Size 1.5'' Design Pressure Class 800 Structure BB, OS&Y, Reduced Port, Bellow Seal Packing Connection Type Socket Weld Operation Handwheel Design Code API 602 End to End ASME B16.10 Connection End ASME B16.11 Pressure & Temperature ASME B16.34 Test & Inspection Standard API 598 Body Material Forged Steel ASTM A105 Trim Material Trim 8 Applicable Temperature -29℃~+425℃ Application W.O.G Origin China Related Knowledge What is a bellw seal valve? For bellow seal globe valves, the lower end bellows is welded on the valve stem to prevent the process fluid from eroding the valve stem. The other end is placed between the valve body and the valve cover to form a static seal. The double seal design ensure that if bellow seal pakcing fails, the stem packing will also function.  The bellow seal globe valves are applicable for media like steam, flammable, explosive, heat transfer oil, high purity, and toxic media etc. Special Tests Besides general tests we will do (hydraulic and air test), we could also do tensile strength test, metallographic test, fugitive emission test, and NDE test (UT,RT,PT,MT) upon customers’ specific requests.

Bellow Seal Globe Valve PN40
Cast Steel Bellow Seal Globe Valve DN65 PN40 1.0619

Dervos bellow seal globe valve is designed as per EN13709 with face to face dimesnsion per EN558. The special designed bellow seal make sure zero leakage from stem. Quick Detail Type Globe Valve Norminal Size DN 65 NorminalPressure PN 40 Construction Bolted Bonnet, Rising Stem, Bellow Sealed ConnectionType RF Flange Operation Handwheel Design Code EN13709 Face to Face EN 558 Connection EN1092 Test & Inspection EN12266 Body Material Carbon Steel 1.0619 Bellow Material SS304, SS316, SS316L and etc ApplicableTemp -29℃~+420℃ Application Water, Oil, Gas Structure Feature 1. Standard design of double-wall bellow seal 2. Heat-dissipating bonnet design; 3. With lubricant storage device; 4, With design of circlip to fix stem nut; 5. Reasonable product structure, reliable sealing performance and good appearance; 6. The sealing surface is welded with Co-based hard alloy, which has good wear resistance, corrosion resistance, anti-friction performance and long service life; 7. Stem has nitriding treatment with good corrosion resistance and anti-friction performance; 8. With position indicator for stem movement;

DN200 PN16 Bellow Seal Globe Valve, RF, Body 1.4408
DN200 PN16 Bellow Seal Globe Valve, RF, Body 1.4408, EN13709

DN200 PN16 Bellow Seal Globe valve is made according to BS EN 13709 standard. The valve body is made of EN 10213 1.4408. It has the structural characteristics of body cover bolt, rising pole bracket, angle type, corrugated pipe seal and structural length of 255mm. Its connection mode is RF. And it has hand wheel operation mode.

1 1/2 inch pressure-sealed globe valve 1500LB SW OSY
1 1/2 inch pressure-sealed globe valve 1500LB SW OSY

The 1 1/2inch 1500LB globe valve,made of one kind of alloy steel F22, is the best answer to working conditions under high pressure and temperature .

Extended Bonnet Gate Valve
Extended Stem Cryogenic Gate Valve SW 1 Inch 1500LB

Made of stainless steel, the cryogenic gate valve has extended bonnet, reduced bore, non-rising handwheel, socket weld connection, complying with API 602. Quick Detail Type Gate Valve Size 1'' Design Pressure ANSI 1500 Construction Extended Stem, Bolted Bonnet, Solid Wedge ConnectionType Socket Weld (SW) OperationType Handwheel Operation Body Material A182 F316L TrimMaterial SS316L Design Code ASME B16.34 Face to Face ASME B16.10 End Connection ASME B16.11 Medium Water, Oil and Gas Origin China Available Modifications for Dervos Valves -Design Pressure -Nominal Diameter -Body Material & Trim Material -Material & Type for Packing and Gasket -Valve Operation Type -Modifications of End Connection -Available Extended Stem or Bonnet -Available By-Pass Valve -Customized Coatings & Packaging Related Knowledge Why do we use extended stem for cryogenic valves? The cryogenic valves are mainly used in low temperature liquid media, like liquefied natural gas and petroleum products. The reasons why we use extended stem for cryogenic valves are as below: 1.To maintain the temperature of stem packing in a proper level, since the very low temperature will influnce the sealing function of stem pakcing. 2.To prevent the heat outside from entering the valve and cause energy loss to the application 3.The long stem structure facilitates the quick replacement of the valve's main part through the valve cover. 4.To prevent the parts (like handwheel) over stem from freezing

API 599 soft seat plug valve WCB 1 Inch Class600
API 599 soft seat plug valve WCB 1 Inch Class600

The 1 inch sleeved type plug valve is made of A216 WCB as per API 599. Thanks to its PTFE seat, the valve has excellent sealing and anti-corrosion performance. The valve is capable in working condition lower than 180 degree.

Ball Valve
DN80 PN16 Trunnion Mounted Ball Valve, Body A105, API6D, Gear Operation

DN80 PN16 trunnion mounted ball valve is made according to API6D standard. The valve body is made of A105. It has the structural characteristics of fixed ball, full bore, anti-fire, anti-static, and anti-flying valve stem. Its connection mode is EN1092-1 B. And it has gear operation mode.

Ball Valve
1/2'' 150LB Forged Steel Floating Ball Valve API608

Made of A182-F316L, 1/2’’ 150LB ball valve is made according to API 608 standard. It has the structural characteristics of floating ball and two-piece ball valve.Its connection mode is RF and there is a handle operation mode.

DN15 PN63 Forged Steel Globe Valve A105N+STL
DN15 PN63 Forged Steel Globe Valve A105N+STL EN1092-1 B

DN15 PN63 Forged Steel Globe Valve is made according to BS 5352 standard. The valve body is made of A105N+STL. It has the structural characteristics of through way type, bolt bonnet and structural length of 130mm. Its connection mode is EN1092-1 B. And it has hand wheel operation mode.

Plug Valve
API 6D Inverted Plug Valve LCB 8 Inch 600 LB Gearbox

The 8 inch plug valve is designed per API 6D with Class 150 RF flange and gearbox operation. The inverted plug valve is made of LCB. Dervos could offer customizing service by providing clients with valves in different sizes, materials, standards, design pressure, structure, operation type and connection type. Quick Detail Type Plug Valve Size 8'' Design Pressure 600LB Construction Inverted Type, Lubricated Type, Pressure Balanced Connection RF Flange Operation Gearbox Design Code API 6D Face to Face ANSI B16.10 End Connection ANSI B16.5 Test & Inspection API 598 Body Material LCB Temperature Range -46℃~+425℃ Application Water, Oil and Gas   Dimension

API600 ALLOY STEEL 10'' 300LB GATE VALVE BB RF OS&Y
API600 ALLOY STEEL 10'' 300LB GATE VALVE BB RF OS&Y

10’’ 300LB gate valve is made according to API 600 standard. The valve body is made of ASTM A217 C5 + STL. It has the structural characteristics of rising stem and bolt cover. The gate valve connected by flange has the operation mode of hand wheel.

Leave a message

    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.

Home

Products

about

contact