English

English

Get a Quote
Products

Hot Products

Company News

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 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


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
 Ductile Iron Gate Valve
Ductile Iron Gate Valve Non Rising Stem PN10 GGG50

The ductile iron gate valve has GGG50 body material and EPDM soft seat. The valve is designed with non-rising stem, RF connection and manual operation, used in fire water. Quick Detail Type Gate Valve Size DN300, DN400 Design Pressure PN10 Construction Non-rising Stem, Soft Seat ConnectionType Flange OperationType Handwheel Operation Body Material GGG50 TrimMaterial Stem 2Cr13, EPDM Seat Medium Water Origin China Hydrostatic Pressure Test Dimension Checking Packing

DN200 PN10 Resilient Gate Valve Non-rising Stem, RF
DN200 PN10 Resilient Gate Valve Non-rising Stem, RF

The gate valve is made of ductile iron GGG50 . The valves disc is rubber-packed to get excellent sealing effect by the rubber's resilient deformation. Non-rising resilient seated gate valves solve the problem in general gate valves such as leakage, rusting etc. And it also saves space.

Gate Valve
DN800 PN10 Cast Iron Gate Valve RF GGG50 DIN

DN800 PN10 gate valve is made according to DIN standard. The valve body is made of GGG50. It has the structural characteristics of F4 drinking water soft gate. Its connection mode is RF, and it has gear operation.

Wafer Check Valve
4" 150LB Dual Plate Wafer Check Valve CF8M Wafer API594

4" 150LB wafer check valve is made according to API 594 standard. The valve body is made of A351 CF8M+STL. It has the structural characteristics of double disc. Its connection mode is wafer.

Angle Bellows Sealed Globe Valve
DN200 PN16 Angle Bellows Sealed Globe Valve RF 1.4408

DN200 PN16 angle bellows sealed 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, exposed pole bracket, angle type, bellow seal. Its connection mode is RF. And it has hand wheel operation mode.

Butterfly Valve
20" 150LB Lined Butterfly Valve API 609 Lug ASME

20" 150LB butterfly valve is made according to API 609 standard. The valve body is made of WCB. Its connection mode is Lug. And it has turbine operation mode.

Carbon Steel Slab Gate Valve
Through Conduit Slab Gate Valve DN200 PN64 Flanged

The through conduit slab gate valve, designed as per DIN standard, has the diversion hole for pipeline cleaning. The PN64 parallel disc gate valve is made of carbon steel with RF flange and handwheel. Quick Detail Type Parallel Slab Gate Valve Nominal Diameter DN 200 Nominal Pressure PN 64 Construction Parallel Slabe Gate Valve, With Diversion Hole, Bolted Bonnet, Resilient Seat Connection Flange Operation Handwheel Operation Body Material Carbon Steel Medium Water, Oil and Gas Origin China Design Feature 1.Parellel disc 2.Soft seat and metal seat for choices 3.Full bore design for pigging and less pressure drop 4.Firesafe design 5.Self relieving function 6.Grease fitting for seat and stem 7.Double block and bleed capability 8.With vent and drain port 9.Tight sealing performance  Material Part Name Material Body & Bonnet A216 WCB, CF8, CF8M, CF3, CF3M Wedge Alloy Steel (face harden treated), Stainless Steel (with Co overlay) Stem Alloy Steel (face erosion-resistant treated) Seat Alloy Steel (face harden treated, beset F plastic), Steel (with Co overlay, best F plastic) Packing PTFE O-Ring NBR, FEP Sealing Grease  

API609 PFA Lined Butterfly Valve LUG FF 20”150LB
API609 PFA Lined Butterfly Valve LUG FF 20”150LB

This 20 inch butterfly valve is plastic lined type one. Its PFA lined disc and its PTFE seat ring enable it a excellent corrosion resistant performance. With a gearbox, it is easy to drive.

4 Inch Gate Valve
Cast Steel 600LB 4 Inch Gate Valve Extended Bonnet BW

The gate valve, made according to API 600, is made of CF8, one kind of cast steel. The 4 inch valve is equipped a handwheel, outside yoke, bolted bonnet and extended bonnet. All the accessories are traceable.

Plug Valve
2" 900LB Lubricated Plug Valve RF 5A API6D Lever

2" 900LB plug valve is made according to API 6D standard. The valve body is made of A995 5A. It has the structural characteristics of oil sealed and full bore. Its connection mode is RF. And it has lever operation mode.

Cast Steel Globe Valve
8" 300LB Cast Steel Globe Valve RF WCB Gear BS1873

8" 300LB globe valve is made according to BS1873 standard. The valve body is made of ASTM A216 WCB+STL. It has the structural characteristics of straight through type and rising stem. Its connection mode is RF. And it has gear operation mode.

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