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Which Inspection Reports Must Be Requested from the Supplier When Purchasing Gate Valves
Which Inspection Reports Must Be Requested from the Supplier When Purchasing Gate Valves
2025-09-12

If you have ever experienced project delays due to valve quality issues, or are in the process of selecting qualified valve suppliers for an upcoming industrial project, then understanding the essential inspection reports required when purchasing gate valves becomes critically important. As a key control component in piping systems, the quality of a valve directly affects the safety and reliability of equipment operation. Therefore, when purchasing gate valves, buyers should not only focus on price and delivery time but also ensure that the supplier can provide complete inspection reports.   Mandatory Inspection Reports   ● Material Test Report (MTR) Purpose: To verify that the main components of the valve, such as the body, bonnet, and stem, meet the specified material standards (e.g., ASTM, DIN, EN). Importance: Prevents valve failure under corrosive or high-pressure conditions due to substandard materials.   ● Pressure Test Report Hydrostatic Test: Checks the valve’s strength under the specified pressure. Air Tightness Test: Ensures the valve does not leak at operating pressure. Importance: Confirms that the valve meets the required design pressure rating.   ● Dimension Inspection Report Content: Verifies whether valve structural length, flange dimensions, wall thickness, etc., comply with design and standards (ANSI, EN, GB). Importance: Ensures proper alignment with the piping system and prevents installation deviations.   ● Non-Destructive Test (NDT) Report Methods: Includes Ultrasonic Testing (UT), Radiographic Testing (RT), Magnetic Particle Testing (MT), and Penetrant Testing (PT). Importance: Verifies that castings or welds are free from internal defects, enhancing the valve’s long-term operational reliability.   ● Coating & Painting Test Report Content: Checks paint thickness, adhesion, hardness, salt spray resistance, etc. Importance: Ensures the valve has strong corrosion resistance for outdoor, marine, or chemical environments.   ● Final Inspection Report Content: Includes comprehensive records of appearance, operational performance, markings, packaging, and other inspection items. Importance: Demonstrates that the valve has undergone strict quality control before delivery.   Conclusion   When purchasing gate valves, requiring suppliers to provide complete inspection reports is not only a verification of product quality but also a guarantee of overall project safety and reliability. By reviewing these reports, customers can reduce operational risks, lower maintenance costs, and extend the service life of their equipment.   Q&A   Q1: Why is a Material Test Report (MTR) mandatory when purchasing gate valves? A1: Material determines the valve’s pressure resistance, corrosion resistance, and service life. Different operating conditions require specific materials, so an MTR is necessary to verify compliance.   Q2: Is Non-Destructive Testing (NDT) require...

What is a Stainless Steel Flanged Ball Valve? Complete Technical Overview and Practical Applications Guide for Industrial Use
What is a Stainless Steel Flanged Ball Valve? Complete Technical Overview and Practical Applications Guide for Industrial Use
2025-08-28

Stainless Steel Flanged Ball Valve is a commonly used industrial valve. Its closure element (the ball) is driven by the valve stem and rotates around the axis of the ball valve, thereby enabling the opening and closing of the pipeline as well as fluid control. In addition to simple on/off functions, stainless steel flanged ball valves can also be used for fluid regulation. In particular, hard-sealed V-port ball valves, relying on the strong shearing force between the V-shaped ball core and the hard alloy-welded seat, are especially suitable for media containing fibers or fine solid particles.   In industrial applications, multi-port stainless steel flanged ball valves can flexibly achieve medium merging, diversion, and flow switching, while also being able to shut off any single passage to ensure normal operation of the remaining pipelines.  these valves generally require horizontal installation to maintain long-term stable performance. According to the driving method, stainless steel flanged ball valves can be classified into manual, pneumatic, and electric types, meeting the needs of different operating conditions.     Standards for Stainless Steel Flanged Ball Valves   To ensure reliable performance and consistent quality, stainless steel flanged ball valves comply with the following standards: • Design and Manufacturing: GB12237-89, API608, API 6D, JPI 7S-48, BS5351, DIN3357; • Flange Dimensions: JB/T74–90, GB9112–9131, ANSI B16.5, JIS B2212–2214, DIN2543,EN1092; • Face-to-Face Dimensions: GB12221-89, ANSI B16.10, JIS B2002, DIN3202,EN558; • Inspection and Testing: JB/T 9092, API 598,API6D. These standards not only guarantee the interchangeability and compatibility of the valves but also ensure their safety and reliability in various industrial environments.     Models and Specifications of Stainless Steel Flanged Ball Valves   Common models and parameters of stainless steel flanged ball valves include: Electric Flanged Ball Valve Q941F: Size DN15–200, Pressure 0.6–10 MPa, Material: Cast Steel / Stainless Steel Carbon Steel ANSI Ball Valve Q41F: Size DN15–200, Pressure 150LB–900LB, Material: Carbon Steel / Cast Steel ANSI Stainless Steel Ball Valve Q41F: Size DN15–200, Pressure 150LB–900LB, Material: Stainless Steel Worm Gear Flanged Ball Valve Q341F: Size DN15–200, Pressure 0.6–6.4 MPa, Material: Carbon Steel / Stainless Steel Pneumatic Stainless Steel Ball Valve Q641F: Size DN15–200, Pressure 0.6–6.4 MPa, Material: Stainless Steel     Main Features of Stainless Steel Flanged Ball Valves   •  Excellent Wear Resistance: The core of the hard-sealed ball valve is overlaid with alloy steel, and the valve seat is surfaced with alloy steel, ensuring strong wear resistance. • Reliable Sealing Performance: Precision grinding guarantees a perfect fit between the ball and the seat, prev...

Shutdown Valves Explained Why They Are Critical for Safe and Efficient Operations
Shutdown Valves Explained Why They Are Critical for Safe and Efficient Operations
2025-08-15

In pipeline systems, the Shutdown Valve is a key component for ensuring safe and efficient operation. Especially when handling high-pressure, high-temperature, flammable, or toxic media, the globe valve, as a common type of Shutdown Valve, plays a critical role. Compared to other types of valves, the structure and working principle of the globe valve make it one of the preferred choices for efficient and safe pipeline control.     1.Basic Function of the Shutdown Valve   In pipeline systems, the Shutdown Valve is a key component for ensuring safe and efficient operation. Especially when handling high-pressure, high-temperature, flammable, or toxic media, the globe valve, as a common type of Shutdown Valve, plays a critical role. Compared to other types of valves, the structure and working principle of the globe valve make it one of the preferred choices for efficient and safe pipeline control.     2.Role of the Shutdown Valve in Safety   Shutdown Valves play a critical safety role in many industrial applications, especially in pipeline systems that handle high-risk, flammable, or toxic media. The superior performance of the Shutdown Valve makes it an ideal choice for preventing dangerous leaks. For example, in the transportation of oil, natural gas, chemicals, and other hazardous substances, the Shutdown Valve can efficiently and quickly close the pipeline flow, preventing harm to the environment and personnel safety. Additionally, Shutdown Valves are widely used in steam systems, cooling water systems, and high-pressure gas pipelines. In these applications, the Shutdown Valve not only ensures safe operation but also effectively regulates flow, controls pipeline pressure, and prevents both overpressure and underpressure in the system, thereby maintaining the stability of the pipeline system.     3.Impact of the Shutdown Valve on Efficient Operation   The Shutdown Valve, known for its reliable sealing performance and low flow resistance, is a crucial tool for achieving efficient flow control in pipeline systems. Compared to other valve types, the design of the Shutdown Valve focuses not only on ensuring a tight shutoff but also on its flow regulation capabilities. While it is not specifically designed for flow control, in certain cases, the Shutdown Valve can serve a limited flow regulation function, especially in systems with relatively low flow rates. For optimal operation, the Shutdown Valve requires regular inspection and maintenance to ensure its sealing integrity and functionality. In high-pressure or high-temperature environments, the valve's sealing surfaces are vulnerable to erosion or damage. Therefore, proper maintenance measures are essential to extend the valve's service life and ensure the safe and efficient operation of the system.     4. Selection and Application of the Shutdown Valve   When selecting the appropriate Shutdown Valve, several factors should be considered: Me...

Double Disc Check Valve
加载中...

Double Disc Check Valve DN3202 PN25 DN100 CF8

  • Payment:

    t:30% when order confirmed, 70% before shipment
  • Product Origin:

    China
  • Color:

    Customization
  • Shipping Port:

    Shanghai, China
  • Lead Time:

    30~60 days Ex Works after order confirmation
  • Material:

    CF8
Inquiry now
Product Detail

The double- disc check valve, made of CF8 stainless steel, has excellent resistance to corrosion. Designed in accordance with DIN 3202, the check valve is about to connect to pipes with WAFER.


Quick Detail

Type

Check Valve

Nominal Diameter

DN100

NominalPressure

PN25

Construction

Double disc/ Dual Plate

Connection

Wafer Type

Design & Manufacture

DIN 3202

End to End 

DIN 3202

Flange End Dimension

DIN 2401

Test & Inspection 

API 598

Temperature Range

-29℃~+425℃

Body Material

A351 CF8

Wedge Material

A351 CF8

Media

W.O.G.


Dervos Packaging

Good packing means good first impression. Just imagine how do you feel differently when seeing two boxes below? And you will know the reason why in Dervos we value packaging so much.



In Dervos, we make sure-

1. Every valve isclean and dry. What do we do?

-Clean the valve before packing

-Add anti-rust oil

-Add flange cover

2. No damageto valves in delivery. How do we achieve this?

-Fix the valve with iron wire

-Separate the valve with soft material

-Layer the valve with plywood

3. Strong box and clear shipping mark


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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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    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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