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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 When the valve is fully open, the gate is completely withdrawn from the flow path, allowing the fluid to pass through with minimal obstruction.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.            

Pressure Seal Bonnet Gate Valve
加载中...

Pressure Seal Bonnet Gate Valve BW 8 Inch 2500LB

  • 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:

    Alloy Steel Gate Valve WC6
  • Method of Operation:

    Gear Operated Gate Valve
Inquiry now
Product Detail

The 8 inch Class 2500 gate valve is designed with pressure seal bonnet, butt weld connection, and gearbox operation. The 8 inch gate valve has carbon steel WCB body and trim 5.


Quick Detail

Type

Gate Valve

Size

8''

Design Pressure

ANSI 2500

Construction

Pressure Seal Bonnet, Flexible Wedge, Metal to Metal Seat

ConnectionType

Butt Weld (SW)

OperationType

Gearbox Operation

Body Material

A217 WC6

TrimMaterial

Trim 5

Design Code

API 600

Face to Face Dimension

ASME B16.10

End Connection

ASME B16.25

Pressure & Temp

ASME B16.34

Medium

Water, Oil and Gas

Origin

China


Dimension & Material

PSB Gate Valve With Butt Weld End

NPS      DN Class 2 2 1/2 3 4 6 8 10 12 14 16 18 20 24
50 65 80 100 150 200 250 300 350 400 450 500 600
L(RF) 900LB 368 419 381 457 610 737 838 965 1029 1130
1500LB 368 419 470 546 705 832 991 1130 1257 1384
2500LB 451 508 578 673 917 1022 1270
L1(BW) 900LB 216 254 305 355 508 660 787 914 991 1092 1346 1473 1600
1500LB 216 254 305 406 559 711 864 991 1067 1194 1697
2500LB 279 330 368 457 610 762 914 1041 1118 1245
L2(RTJ) 900LB 371 422 384 460 613 740 841 968 1038 1140
1500LB 371 422 473 549 711 841 1000 1146 1276 1407
2500LB 454 514 584 683 927 1038 1292
H(Opne) 900LB 554 637 680 796 1084 1372 1494 1550 1960 2210
1500LB 554 637 767 875 1094 1372 1655 1834 2150 2260 2460 2721 2940
2500LB 610 654 753 850 1254 1374 1685 1894 2226 2382 2585
W 900LB 300 350 350 400 560 460* 610* 610* 610* 760*
1500LB 300 450 450 560 305* 460* 610* 610* 760* 760*
2500LB 500 500 600 600 460* 460* 610*
Weight   (RF) 900LB 50 84 92 154 341 622 950 1295 1720 2380
1500LB 60 91 128 182 394 795 1370 2120 2800 3870
2500LB 121 175 195 229 720 1295 2250
Weight   (BW) 900LB 39 64 82 120 266 524 760 1090 1450 2018
1500LB 46 71 85 130 292 578 974 1615 2010 2815 3315 4150 5219
2500LB 88 135 144 158 500 892 1550 1978 2580 3780 5988
*Manual gear operator is recommended



No. Part WCB WC6 WC9  C5 CF8 CF8M
1 Body A216 WCB A217 WC6 A217 WC9 A217 C5 A351 CF8 A351 CF8M
2 Seat A182 F6a A182 F22 A182 F22 A182 F5 A182 F304 A182 F316
3 Wedge A216 WCB A217 WC6 A217 WC9 A217 C5 A351 CF8 A351 CF8M
4 Stem A182 F6a SAEHNV3 A182 F304 A182 F316
5 Stuffing Box A216 WCB A217 WC6 A217 WC9 A217 C5 A351 CF8 A351 CF8M
6 Seal Ring ANSI 316L Flexible Graphite+316
7 Split Ring Steel F6 F6 F6 A182 F304 F316
8 Back Ring Steel Steel Steel Steel SS SS
9 Bolt A193 B7 A193 B7 A193 B7 A193 B7 A193 B8 A193 B8
10 Nut A194 2H A194 2H A194 2H A194 2H A194 Gr.8 A194 Gr.8
11 Yoke A216 WCB A217 WC6 A217 WC9 A217 C5 A351 CF8 A351 CF8M
12 Bolt A193 B7 A193 B7 A193 B7 A193 B7 A193 B8 A193 B8
13 Nut A194 2H A194 2H A194 2H A194 2H A194 Gr.8 A194 Gr.8
14 Packing Plate ANSI 410 ANSI 410 ANSI 410 ANSI 410 ANSI 304 ANSI 316
15 Packing Flexible Graphite(Braided and Ring) or PTFE
16 Split Pin Steel Steel Steel Steel Steel Steel
17 Eyebolt A193 B7 A193 B7 A193 B7 A193 B7 A193 B8 A193 B8
18 Gland A182 F6 A182 F6 A182 F6 A182 F6 A182 F304 A182 F316
19 Gland Flange A105 A105 A105 A105 A182 F304 A182 F316
20 Nut A194 2H A194 2H A194 2H A194 2H A194 Gr.8 A194 Gr.8
21 Stud A193 B7 A193 B7 A193 B7 A193 B7 A193 B7 A193 B7
22 Stem Nut Ni-resist A439-D2
23 Gear Box Purchased
24 Protector Steel
25 Nameplate ANSI 304
26 Rivet ANSI 304


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