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Are Gate Valves Full Port?
Are Gate Valves Full Port?
2026-03-13

In industrial piping systems, gate valves are generally considered low-resistance isolation valves. When the valve is fully open, the gate is completely withdrawn from the flow path, allowing the fluid to pass through with minimal obstruction.   However, from a strict engineering perspective, not all gate valves are classified as full port valves.   If the seat bore is equal to or very close to the pipeline internal diameter, the flow experiences little or no restriction. In this case, the valve can be considered full port (or near full port). This design is commonly used in oil and gas pipelines, water transmission systems, and other applications where low pressure drop is required.   If the seat bore is slightly smaller than the pipe internal diameter, a minor flow restriction will occur inside the valve. In such cases, the valve is more accurately described as reduced bore. This configuration is more common in smaller sizes or cost-optimized valve designs.   In engineering practice, a simple selection logic can be applied: ● If the system requires minimum flow resistance or pipeline pigging, the valve bore must match the pipeline diameter. ● If the valve is used for general isolation purposes, most standard gate valves can already meet the required flow capacity.   Therefore, a concise conclusion can be drawn: Gate valves are typically close to full port designs, but whether they are truly full bore depends on whether the seat bore equals the pipeline internal diameter.   QA   Q1: Are gate valves always full bore?Not necessarily. If the seat bore equals the pipe internal diameter, the valve can be considered full bore. If it is slightly smaller, it is classified as reduced bore.   Q2: Why do gate valves have relatively low flow resistance?When the valve is fully open, the gate is completely removed from the flow path, allowing the fluid to pass through in a nearly straight line, which results in low pressure drop.   Q3: Are gate valves suitable for high-flow pipelines?Yes. If the system requires low pressure drop, gate valves are commonly used.   Q4: Is the concept of full port the same for gate valves and ball valves?Not exactly. For ball valves, the bore size is determined by the ball port diameter, while for gate valves, it is mainly determined by the seat bore diameter.

Installation of Large Diameter Ball Valves
Installation of Large Diameter Ball Valves
2026-03-09

Large diameter ball valves are commonly used in industries such as petroleum and chemical processing, power generation, long-distance pipeline transportation, and large-scale water treatment systems. If installation is not performed correctly, it may lead to sealing leakage, valve jamming, or structural stress damage. Therefore, proper installation practices are essential to ensure long-term stable operation.   1. Pre-installation Inspection   If pre-installation inspection is insufficient, operational failures are more likely to occur during service. First, inspect the valve body for transportation damage. If scratches, impact marks, or deformation are found on the valve body or sealing surfaces, installation should be stopped and the supplier should be contacted.   Next, verify valve model, pressure rating, and connection standards. If the system design pressure does not match the valve pressure class, operational safety risks may occur. For example, if a low-pressure class valve is mistakenly used in a high-pressure pipeline system, the valve body may experience plastic deformation under water hammer impact.   It is also necessary to check the condition of the ball surface and sealing rings. If there are scratches on the ball surface, sealing performance will be reduced. This is especially critical in gas transmission systems where micro-leakage is more likely.   2. Installation Direction   Large diameter ball valves usually have a flow direction marking. If the installation direction is incorrect, the following problems may occur: If the fluid flow direction matches the design direction, the operating torque will remain more stable. If the valve is installed in reverse, the stem may experience increased mechanical load, which will accelerate stem wear during long-term operation. For double-seal bidirectional ball valves, although bidirectional flow is allowed, installation according to the marked flow direction is still recommended to ensure more uniform sealing stress distribution. In high-temperature or steam systems, if the installation direction is incorrect, thermal expansion may accelerate sealing ring aging.   3. Pipeline Stress Control   Large diameter ball valves are heavy. If installed without proper support, additional bending moments may be transferred to flange connections. If pipeline systems experience axial displacement, pipeline supports should be installed for segmented fixation. If support structures are not provided, the valve body may bear long-term gravitational tensile load, eventually causing flange seal failure. It is generally recommended to install independent supports on both sides of large diameter ball valves. If the pipeline system is subject to thermal expansion and contraction, expansion compensation devices must be installed; otherwise, sealing surfaces may gradually fail.   4. Bolt Tightening Process   Flange connections of large diameter ball valves usually ...

Unite Strength, Create the Future Together --Dervos Annual Grand Event Successfully Concluded
Unite Strength, Create the Future Together --Dervos Annual Grand Event Successfully Concluded
2026-03-02

This year’s Dervos annual conference was noticeably more grand and well-organized than in previous years.   In the morning session, each department delivered its annual work summary, reviewing key projects and achievements over the past year. Teams also openly shared the challenges encountered during implementation and the practical experience gained along the way.   Through this cross-department exchange, everyone developed a clearer understanding of one another’s responsibilities and workflows, laying a stronger foundation for future collaboration and communication.     In the afternoon session, the Outstanding Employee awards were presented. Each nominee shared their work achievements and practical experience, demonstrating a strong sense of responsibility and execution across different roles. It is precisely this proactive mindset, collaborative spirit, and down-to-earth working approach of Dervos employees that drives the team steadily toward its shared goals.     Showing up on time every single day throughout the year — that’s quite an achievement. Ian has now received the Perfect Attendance Award for two consecutive years.     During the annual conference, Dervos also presented medals and exclusive commemorative gifts to employees who have completed five years of service.     Dervos values the long-term dedication and consistent commitment of its team members, and sincerely appreciates the trust and contributions they have made over the years. For many at Dervos, the company is not only a platform for professional growth, but also a stage where shared goals and collective efforts come to life. In the evening, the annual conference transitioned into the banquet segment. Performances and interactive games were seamlessly interspersed, creating a relaxed yet organized atmosphere.     Laughter and cheers echoed throughout the venue, and in the moment the camera shutter clicked, the excitement and joy were captured in a single frame.     Eric said: "Let’s dream together, DERVOS's dream. A dream where we all play a part, piece by piece, it becomes a reality." For Dervos, the annual meeting is not just about "summarizing the year," but about bringing our hearts together, strengthening our resolve in doing the same thing, and then continuing to move forward, step by step, with steady progress.            

Carbon Steel Slab Gate Valve
加载中...

Through Conduit Slab Gate Valve DN200 PN64 Flanged

  • Payment:

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

    China
  • Color:

    Customization
  • Shipping Port:

    Shanghai China
  • Lead Time:

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

    Carbon Steel Gate Valve, Cast Steel Gate Valve
  • Method of Operation:

    Manual Gate Valve
Inquiry now
Product Detail
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

Slab Gate Valve Manufacturers


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


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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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