Ball valves and plug valves differ significantly in several aspects, including structure, operating principle, mode of operation, flow control capability, sealing performance, and application scenarios. These differences enable the two types of valves to perform distinct roles in their respective fields. Structural Differences The ball valve, a design evolved from the plug valve, utilizes a spherical element as its core component. By rotating the ball 90° around the stem axis, the valve can be opened or closed. Its structure is straightforward, consisting primarily of a spherical closure element with a through-bore housed within the valve body. In contrast, the structure of a plug valve is more complex. It comprises multiple components such as the valve body, bonnet, plug, seat, and stem. The closure element is a cylindrical or tapered plug that controls flow by rotating 90°, aligning or misaligning the port in the plug with the flow passage in the valve body to achieve opening or shutoff. Operating Principle The operating principle of a ball valve relies on the rotation of the ball to control the on-off flow of fluid. When the ball is in tight contact with the valve seat, the clearance between them is completely sealed, thereby preventing fluid leakage. When the ball rotates to a position disengaged from the seat, the fluid is allowed to flow freely through the passage inside the valve body. The operating principle of a plug valve differs in that it primarily controls the flow passage by rotating the plug element to open or close the valve. In a plug valve, the plug is connected to the stem and rotates together with it to achieve flow control. The closure element is a tapered plug with a port, and the flow passage is designed to be perpendicular to the axis of the plug. This configuration enables the plug valve to operate more efficiently and reliably during opening and closing. The operation of a ball valve is notably simple, requiring only a 90-degree rotation to achieve opening or closing. This design allows the flow passage to be opened or shut off quickly and smoothly when the ball is rotated by 90 degrees, providing both convenience and efficiency. In addition, ball valves offer relatively low flow resistance in the fully open or fully closed position, making them particularly suitable for applications that require rapid on-off operation. By contrast, the operation of a plug valve is comparatively more complex, as several turns are typically required to complete the opening or closing action. The valve plug is designed in a cylindrical or tapered form and regulates fluid flow through rotation. Nevertheless, plug valves demonstrate excellent performance in flow regulation, enabling precise adjustment of the flow passage diameter and accurate control of flow rate. However, due to the relatively complicated operating process, plug valves are not well suited for frequent operation...
In industrial valve systems, a high-quality blind plate valve ensures safe and efficient operation of equipment. It is suitable for gas pipelines in metallurgy, chemical processing, petroleum, and municipal systems, serving as an effective device for positive gas isolation. Working Principle and Features The blind plate valve consists of left, center, and right valve bodies, a valve plate, shafts, a compensator, and two drive units (for clamping and travel respectively). The clamping mechanism uses a drive assembly to actuate a linkage system, enabling three lead screws to operate synchronously and press the valve bodies against the valve plate to achieve sealing. This design provides good synchronization and uniform sealing force distribution. Positioning rollers are installed along the outer lower edge of the valve plate to enhance sealing reliability and ensure overall stability and sealing accuracy during operation, thereby extending the service life of the valve. Valve Operating Sequence The clamping drive unit actuates the crank and linkage mechanism, causing the lead screws to rotate synchronously and retract the center body from the sealing surfaces (release condition). Guide wheels installed on the center body move laterally and simultaneously drive the valve plate. When the valve bodies are fully opened, the valve plate is positioned between the sealing faces of the left and right bodies, and the sealing surfaces are completely disengaged. The plate drive unit is then activated. Through a lever arm mechanism, the valve plate rotates, bringing the blind plate into the pipeline position. The clamping drive unit is started again to fully clamp the valve plate, completing valve closure. Valve Opening The clamping drive unit first fully releases the valve bodies. The turning drive unit then rotates the valve plate so that the through-port aligns with the pipeline. Finally, the clamping electric actuator presses the valve plate to complete the opening operation.
Wide-body ball valves and single-piece ball valves are both types of ball valves used for controlling the on/off flow of medium in pipelines. Both wide-body and single-piece ball valves feature a one-piece (integral) body design, unlike split-body designs. This differs from two-piece and three-piece ball valves, which have segmented valve bodies. For internally threaded wide-body ball valves, the valve body is made from round or hexagonal stock, using either bar material or forged components. The ball core features a reduced-diameter design and is inserted from one side of the valve body. The stem uses an internal anti-blowout structure. Flat surfaces are machined on both the inlet and outlet sides of the body to facilitate assembly of the ball valve and allow the use of wrenches during pipeline installation. In wide-body ball valves, the stem stuffing box is relatively shallow, and the internal packing volume is limited, resulting in a moderate sealing performance of the stem. Therefore, these valves are more suitable for low-pressure medium applications. In contrast, two-piece and three-piece ball valves feature stem stuffing box structures that provide reliable sealing for high-pressure medium applications. The structure of flanged wide-body ball valves is essentially the same as that of internally threaded wide-body ball valves. Typically, the flange is connected to the intermediate valve body via threaded fasteners, although some designs utilize a forged one-piece structure. Externally threaded wide-body ball valves can use a union-type structure, where the union is directly welded to the pipeline and connects to the external threads on the valve body. This design allows for easy disassembly and reassembly during valve maintenance or replacement without requiring separate unions on the pipeline. The valve bodies of single-piece internally threaded ball valves and single-piece flanged ball valves are manufactured using casting processes, with the ball core featuring a reduced-diameter design. The stem uses an internal anti-blowout structure. The inlet and outlet ends of single-piece internally threaded ball valves have a hexagonal shape, similar to conventional internally threaded valves, to facilitate wrench operation and secure installation. In single-piece flanged ball valves, the flange and valve body are cast as a single unit, eliminating the need to machine and assemble the flange separately as in wide-body flanged ball valves. This approach reduces cost and simplifies the manufacturing process. Single-piece wafer-style ball valves have a shorter valve body length, making them more suitable for pipelines with limited space. Wide-body and single-piece ball valves both use a reduced-diameter ball design, resulting in higher flow resistance compared with two-piece and three-piece ball valves. The main differences are as follows: Valve Body Manufacturing Process ● Wide-bo...
This 1/2 Inch plug valve is made of A216 WCB, according to API598.With little required maintenance and trouble-free operation, a high integrity bubble-tight seal is provided both in-line and to atmosphere.
Payment:
30% when order confirmed, 70% before shipmentProduct Origin:
ChinaColor:
CustomizationShipping Port:
Shanghai, ChinaLead Time:
30~60 days Ex Works after order confirmationMaterial:
A216 WCBMethod of Operation:
WrenchQuick Detail
|
Type |
Plug Valve |
|
Nominal Diameter |
1/2 Inch |
|
NominalPressure |
800LB |
|
Construction |
Sleeve Type |
|
Connection |
NPT |
|
Design & Manufacture |
API599 |
|
Ends End Dimension |
ASME B1.20.1 |
|
F to F Dimension |
ASME B16.10 |
|
Pressure Test |
API598 |
|
Body Material |
A216 WCB |
|
Plug Material |
A315 CF8 |
|
Temp. Range |
≤120°C |
|
Media |
Water, Oil, Gas, etc |
Features
-Free of cavities
-Maintenance free – self lubricating
-Easy accessible adjustment of the plug, even with mounted actuator
-Bi-directional in-line bubble-tight seal independent of line pressure
-Multiple external bubble-tight seals independent of line pressure
-Positive flow direction indication
Technical Drawing
Witness Tests
Packing
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The 6 inch sleeved plug valve features in non lubricated design and soft seat. The full port plug valve is made of carbon steel body and PTFE seat as per API 6D, with Class 150 flange connection. Quick Detail Type Plug Valve Size 6'' Design Pressure 150LB Construction Self-Lubricated Type, Sleeved Type, Soft Seat Connection Type RF Flange Operation Gearbox Operation Design Code API 599 Face to Face ASME B16.10 End Connection ASME B16.5 Pressure & Temp ASME B16.34 Test & Inspection API 598 Body Material A216 WCB Temperature Range -29℃~+425℃ Application Water, Oil, Gas Material & Dimension No Part Name Carbon steel to ASTM Stainless steel to ASTM WCB LCB CF8 CF8M CF3 CF3M 1 Body A216 WCB A350 LCB A351 CF8 A351 CF8M A351 CF3 A351 CF3M 2 Bonnet A216 WCB A350 LCB A351 CF8 A351 CF8M A351 CF3 A351 CF3M 3 Plug A105 A182 F304 A351 CF8 A351 CF8M A351 CF3 A351 CF3M 4 Stem A182 F6 A182 F6 A182 F304 A182 F316 A182 F304L A182 F316L 5 Seat Ring PTFE 6 Gasket PTFE or Stainless Steel and Graphite 7 Stem Seat PTFE PTFE PTFE PTFE PTFE PTFE 8 Small spring 17-17PH 9 Small ball A182 F304 or A182 F316 10 Gland A182 F6 A182 F6 A182 F304 A182 F316 A182 F304L A182 F316L 11 Gland Flange A216 WCB A350 LCB A351 CF8 A351 CF8M A351 CF3 A351 CF3M 12 Stem packing PTFE or Graphite 13 Bonnet bolt A193 B7 or A320 L7 or A320 B8 or A193 B8M 14 Bonnet nut A194 2H or A194 4 or A194 8 Class 150 DN mm 15 20 25 40 50 65 80 100 150 200 250 300 NPS in 1/2 3/4 1 1 1/2 2 2 1/2 3 4 6 8 10 12 L(RF) mm 108 117 127 165 178 191 203 229 394 457 533 610 in 4.25 4.6 5 6.5 7 7.5 8 9 15.5 18 21 24 L1(BW) mm 140 152 165 190 216 241 283 305 457 521 559 635 in 5.5 6 6.5 7.48 8.5 9.5 11.13 12 18 20.5 22 25 L2(RTJ) mm 119 129.7 139.7 178 191 203 216 241 406 470 546 622 in 4.69 5.11 5.5 6.9 7.5 8 8.5 905 16 18.5 21.5 24.5 H mm 59 63 75 92 153 165 195 213 272 342 495 580 in 2.3 2.5 2.95 3.74 6.02 6.5 7.68 8.39 10.7 13.5 19.5 22.85 D(W) mm 130 130 160 230 400 400 600 850 1100 1500 350* 350* in 5.1 5.1 6.3 9 15.74 15.74 23.62 33.46 43.3 59 13.8 13.8 Weight (Kg) RF 2.3 3 4.5 7 15 20 25 40 97 160 240 390 BW 2.0 2.5 3.8 5.8 12 17 21 36 92.8 154 227 365
The PTFE sleeved plug valve is made of CF3 body and plug as per API 6D. The valve owns the feature of reduced port and good sealing performance. We call this type of valve as non lubricated plug valve or self lubricated plug valve. Quick Detail Type Plug Valve Size 2'' DesignPressure 300LB Construction Sleeved Type, Non Lubricated Type, Soft Seat ConnectionType Flange Operation Lever Operation Design Code API 599, API 6D Face to Face ASME B16.10 End Connection ASME B16.5 Pressure & Temp ASME B16.34 Test & Inspection API 598 Body Material CF3 Temperature Range -29℃~+120℃ Application Water, Oil, Gas Dimension Checking Hydrostatic Testing
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.
Non-Lubricated, Sleeved Plug Valves incorporate state-of-the-artPPL seat design. With little required maintenance and trouble-free operation, the 3 inch 150 LB valve will ensure a high integrity bubble-tight seal.
DN250 PN25 plug valve is made according to API599 standard. The valve body is made of A216 WCB. It has the structural characteristics of soft sealing plug valve. Its connection mode is RF. And it has turbine operation mode.
DN50 PN40 plug valve is made according to API 599 standard. The valve body is made of A216 WCB. It has the structural characteristics of ferrule type, reduced diameter. Its connection mode is RF. And it has lever operation mode.
3/4" 1500LB gate valve is made according to API602 standard. The valve body is made of ASTM A105N. It has the structural characteristics of body cover welding. Its connection mode is SW. And it has handwheel operation mode.
2" 1500LB wafer check valve is made according to API 594 standard. The valve body is made of A182 F316+STL 6. It has the structural characteristics of double disc, wafer type and built-in type. Its connection mode is RF.
DN25 PN40 Flange Gate Valve is made according to API602 standard. The valve body is made of A182-F316Ti. Its connection mode is EN1092-1 B1. And it has Hand Wheel operation mode. Product Parameters Type Stainless Steel Gate Valve Size DN25 Pressure PN40 Connection EN1092-1 B1 Operation Hand Wheel Body Material A182-F316Ti Design Norm API 602 Flange dimension EN 1092 Material conform AISI/ASTM Test & Inspection Code EN 12266 Temperature -29 ~ 120°C Applicable Medium Water, Oil and Gas Features 1.F316Ti stainless steel body provides enhanced resistance to intergranular corrosion and elevated-temperature service. 2.DN25 PN40 gate valve designed to API 602 with EN1092-1 B1 flange ensures stable operation and tight isolation in process pipelines. Technical Drawing Dimension Checking Pressure Testing Spectrum Inspection Report
The 1 inch forged steel gate valve is constructed of integral flange, bolted bonnet, rising stem and solid wedge and bolted bonnet. The valve has the design standard API 602 and inspection standard API 598. Dervos could offer customizing service by providing clients with valves in different sizes, materials, standards, design pressure, structure, operation type and connection type.
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;
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.
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