In a wedge gate valve, the gate sealing surfaces are wedge-shaped, forming a specific angle relative to the gate centerline. The gate is driven downward by the valve stem to achieve closure. As the stem thrust increases, the normal force acting on the wedge-shaped sealing surfaces also increases, creating a forced sealing effect. This design significantly improves sealing performance under low-pressure conditions. During opening, the gate sealing surfaces disengage from the seat immediately, which helps reduce wear on the sealing faces and extends the service life of the valve. Applicable Standards for Wedge Gate Valves Wedge gate valves are commonly manufactured in accordance with the following standards: ● GB/T 12234-2019 – Steel gate valves with bolted bonnet for petroleum and natural gas industries ● GB/T 12232-2005 – General-purpose flanged cast iron gate valves ● API Standard 600 (2015) – Steel gate valves for petroleum and natural gas industries Types of Wedge Gate Valve Gates Wedge gate valves are typically available in three gate configurations:Solid wedge gate, Flexible wedge gate, Double wedge gate. The flexible wedge gate and double wedge gate rely on controlled deformation of the sealing surfaces to achieve improved contact with the valve seat. This design enhances sealing reliability and effectively prevents gate binding or jamming caused by temperature variations, ensuring smooth operation even under fluctuating thermal conditions. Parallel Slide Gate Valve Design and Sealing Principle In a parallel slide gate valve, the sealing surfaces at both the inlet and outlet ends of the gate are parallel to the gate centerline. For single-gate configurations, sealing is primarily achieved by the medium pushing a floating gate or floating seat into position. In double-gate configurations, sealing can be accomplished through springs or an expansion mechanism between the gates. Throughout the opening and closing process, the gate and seat sealing surfaces remain in constant contact, ensuring reliable sealing. Applicable Standards for Parallel Slide Gate Valves Common standards for parallel slide gate valves include: ● GB/T 23300-2009 – Parallel slide gate valves ● JB/T 5298-2016 – Steel parallel slide gate valves for pipelines ● API 6D – Pipeline valves for petroleum and natural gas industries Types and Features of Parallel Slide Gate Valves Parallel slide gate valves are available in single-gate and double-gate configurations. ● Gates may include flow-through holes or be solid. Gates with flow-through holes match the seat inner diameter, facilitating cleaning and drainage of the pipeline. ● Sealing can be configured at the inlet end, outlet end, or at both ends, depending on application requirements. This design ensures flexibility in sealing arrangements while maintaining reliable oper...
Damage to valve sealing surfaces is typically the result of multiple contributing factors, including material selection, operating conditions, operating practices, and maintenance. The following is a categorized summary of the most common causes: 1. Mechanical Damage ● Wear: Solid particles in the medium (such as sand or welding slag) erode the sealing surface, resulting in scratches or grooves. ● Abrasive scuffing: Frictional wear caused by relative movement of the sealing surfaces during valve opening and closing, particularly in metal-to-metal sealing pairs. ● Impact damage: Deformation of the sealing surface caused by high-velocity fluid impingement or rapid valve opening and closing, leading to impact loading. 2. Chemical Corrosion ● Media corrosion: Acidic, alkaline, or oxidizing media directly attack the sealing surface material, such as metal corrosion caused by H₂S or chloride ions. ● Electrochemical corrosion: When sealing pairs made of dissimilar metals are exposed to an electrolyte, galvanic corrosion may occur due to electrochemical cell formation. ● Erosion–corrosion: The combined effect of corrosive media and high-velocity flow accelerates material loss on the sealing surface. 3. Thermal Damage ●Thermal fatigue:Frequent temperature fluctuations cause repeated thermal expansion and contraction of the sealing surface, leading to cracking or deformation. ●High-temperature oxidation:At elevated temperatures, the sealing surface may undergo oxidation, hardening, or burn-off, as commonly observed in steam valve applications. ●Thermal shock:Sudden exposure to high- or low-temperature media can cause cracking of the sealing surface, such as during rapid condensation or cold media ingress. 4. Improper Installation and Operation ●Installation misalignment: Incorrect valve installation or excessive piping stress can result in uneven loading on the sealing surfaces. ●Over-tightening: Excessive preload applied to the valve stem or bolting may crush or deform the sealing surface, particularly in soft-seated valves or soft sealing gaskets. ●Rough operation: Rapid opening and closing or excessive operating force can cause impact damage to the sealing surfaces. 5. Material Defects ●Improper material selection: The sealing surface material lacks sufficient resistance to process media, high temperature, or wear, such as the use of carbon steel in acidic service. ●Manufacturing defects: Defects in the hardfacing or overlay layer, including porosity, slag inclusions, or improper heat treatment, reduce wear resistance and overall sealing performance. 6. Abnormal Operating Conditions ●Cavitation / flashing: Pressure fluctuations in the fluid generate vapor bubbles that collapse and impact the sealing surface, a phenomenon commonly observed in valves installed downstream of pumps. ●Scaling / deposition: Impurities in the medium accumulate on the sealing surface, impairing tight shutoff, suc...
In 2025, Dervos organized its annual team trip, a five-day journey to Chongzuo, Weizhou Island, and Nanning in Guangxi Province. The trip aimed to provide relaxation and strengthen team communication, offering a well-paced and content-rich experience that combined natural landscapes with local cultural immersion. In Chongzuo, the team focused on nature sightseeing. Bamboo rafting tours allowed close observation of the local ecology and offered opportunities to see rare species such as the white-headed leaf monkey. The group also visited Detian Waterfall, experiencing its scale and flow firsthand. The overall itinerary was designed with a relaxed pace, providing ample time for rest and team bonding. Next, the team traveled to Weizhou Island. The volcanic landforms and coastal scenery added a unique visual dimension to the journey. Beyond sightseeing, participants engaged in local agricultural activities, including dragon fruit picking and banana harvesting, gaining insight into local lifestyles. The team also visited several beaches, fully appreciating the island environment. The final stop was Nanning. Team members explored the night market, sampled local specialties, and experienced the city’s daily life, bringing the Guangxi trip to a relaxed conclusion. This annual trip allowed the Dervos team to foster more natural communication and connection outside of work, recharging energy for the months ahead. Dervos remains committed to its guiding principle: I come, I see, I conquer!
The 1 1/2inch 1500LB globe valve,made of one kind of alloy steel F22, is the best answer to working conditions under high pressure and temperature .
Payment:
30% when order confirmed, 70% before shipmentProduct Origin:
ChinaColor:
CustomizationShipping Port:
Shanghai, ChinaLead Time:
30~60 days Ex Works after order confirmationMaterial:
F22Method of Operation:
HandwheelQuick Detail
|
Type |
Globe Valve |
|
Size |
1 1/2 Inch |
|
Pressure |
1500LB |
|
Construction |
Pressure Sealed；OSY |
|
Connection Type |
Socket Weld |
|
Operation Type |
Handwheel Operated |
|
Design Code |
API602 & ASME B16.34 |
|
Socket Weld Dimension |
ASME B16.11 |
|
Test & Inspection |
API 598 |
|
Body Material |
F22 |
|
Trim Material |
SS304+STL |
|
Temperature Range |
-29~38℃ |
|
Application |
Water, Oil, Gas |
|
Origin |
China |
Features
1. Flexible wedge gate, full guide;
2. Compact structure, reliable sealing, excellent performance and nice appearance;
3. Only one sealing surface on the valve body and disc brings convenient maintenance;
4. Packing can be replaced in-site;
Technical Drawing
Dimension Check
Nameplate&Packaging
About Dervos
Xiamen Dervos Valves Industry Co.,Ltd (stock code 861601), founded in June 2008, is a one-stop industrial valves supplier integrated of R&D, manufacture, resource integration, and trade service. For 12 years, Dervos has been committed to finding solutions for industrial needs and providing professional service for both general and specialized valves.
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.
The 6 Inch PSB globe valve has 1500LB design pressure, butt weld end, and gearbox. The full bore globe valve is made of carbon steel WCB body and trim 5 material. Quick Detail Type Globe Valve Size 6'' Design Pressure Class 1500 Construction Pressure Seal Bonnet, Plug Type Disc, Rising Stem Connection Type Butt Weld Operation Type Bevel Gearbox Opearted Design Code BS 1873 End to End ASME B16.10 Connection End ASME B16.25 Pressure & Temperature ASME B16.34 Test & Inspection Standard API 598 Body Material Cast Steel WCB Trim Material Trim NO. 5 Temperature Range -29℃~+425℃ Application WOG Origin China Material & Dimension NPS DN Class 2 2 1/2 3 4 6 8 50 65 80 100 150 200 L(RF) L1(BW) 900LB 368 419 381 457 610 737 1500LB 368 419 470 546 705 832 2500LB 451 508 578 673 917 1022 L2(RTJ) 900LB 371 422 384 460 613 740 1500LB 371 422 473 549 711 841 2500LB 454 514 584 683 927 1038 H(Opne) 900LB 550 605 678 798 930 1230 1500LB 550 605 866 956 1260 1263 2500LB 560 720 755 1230 1791 2086 W 900LB 350 350 400 450 458 610* 1500LB 400 400 450 560 610* 610* 2500LB 400 450 560 310* 610* 760 Weight (RF) 900LB 78 108 102 142 400 960 1500LB 85 110 135 230 660 1590 2500LB 140 168 247 620 1500 3200 Weight (BW) 900LB 66 91 87 128 355 868 1500LB 77 101 122 209 595 1440 2500LB 100 118 180 438 1148 2594 *Manual gear operator is recommended No Part Name Carbon steel to ASTM Alloy steel to ASTM Stainless steel to ASTM WCB WC6 WC9 C5 CF8 CF8M CF3 CF3M 1 Body A216 WCB A217 WC6 A217 WC9 A217 C5 A351 CF8 A351 CF8M A351 CF3 A351 CF3M 2 Seat Ring A105 A182 F11 A182 F22 A182 F5 A182 F304 A182 F316 A182 F304L A182 F316L 3 Disc A105 A182 F11 A182 F22 A182 F5 A182 F304 A182 F316 A182 F304L A182 F316L 4 Stem A182 F6 A182 F304 A182 F304 A182 F316 A182 F304L A182 F316L 5 Disc nut A182 F6 A182 F304 A182 F304 A182 F316 A182 F304L A182 F316L 6 Cap SS Spiral Wound graphite or SS Spiral Wound PTFE 7 Body Seal Flexible Graphite+316 8 Adjustment Gasket F6 F6 F316 9 Stem packing Flexible Graphite+316 10 Gland Nut A194 2H A194 8 11 Gland Eyebolt A193 B7 A193 B8 12 Pin Carbon steel or Stainless Steel 13 Cap Nut Carbon steel or Stainless Steel 14 Gland A182 F6 A182 F304 A182 F316 A182 F304L A182 F316L 15 Gland Flange A216 WCB A351 CF8 16 Yoke A216 WCB A351 CF8 17 Stem Nut A439 D2 or B148-952A 18 Screw Carbon steel 19 Handwheel Ductile Iron or carbon steel 20 Name Plate Stainless steel or Aluminum 21 Washer Carbon steel 22 Nut Carbon steel or Stainless Steel Related Knowledge Why do we use pressure seal bonnet? Pressure sealed bonnet are often used for valves with high design pressure. The higher the internal pressure gets, the greater the sealing force beween body and bonnet become. For bolted bonnet valves, the body and bonnet are joined by studs and nuts with a gasket between the flange faces to facilitate sealing. However,as system pressure increases,the potential for leakage through the body and bonnet increases. But for pressure sealed valve, “bonnet take-up bolts” to pull the bonnet up and seal against the pressure seal gasket. That is why when pressure increase, the performance of pressure seal gasket between body and bonnet becomes better.
The 1 1/2inch 1500LBglobe valve,made of A105N are best suited for throttling application at high pressure and temperature.
The Class 300 flanged ball valve has cast steel WCB body, stainless steel ball, stem, seat ring along with Devlon seat insert. We also supply more types of trunnion mounted ball valve, accept customized. Design Feature 1.Firesafe design as per API 607 2.With sealant injection for self lubricating 3.With antistatic design 4.With anti-blowout stem 5.With vent and drain port 6.Full bore design 7.Three-piece type and trunnion ball 8.Gear operated for easy operation Quick Detail Type Ball Valve Size 24" Pressure ANSI 300 Construction Trunnion Type Ball, 3-Piece Body, Side Entry, Full Bore Connection Flange Connection Operation Gearbox Operation Body Material ASTM A216 WCB Design Code API 6D Pressure & Temp Code ASME B16.34 Face to Face ASME B16.10 End Connection ASME B16.5 Test & Inspection Code API 598, API 6D Fire Safe API 607 Temperature Range -29℃~+200℃ Medium WOG Origin China Dimension CLASS 300 DN mm 50 65 80 100 150 200 250 300 350 400 450 500 600 700 NPS in 2 2.5 3 4 6 8 10 12 14 16 18 20 24 28 L (RF) mm 216 241 283 305 403 502 568 648 762 838 914 991 1143 1346 in 8.5 9.5 11.13 12 15.88 19.75 22.38 25.5 30 33 36 39 45 53 L1 (BW) mm 216 241 283 305 457 521 559 635 762 838 914 991 1143 1346 in 8.5 9.5 11.13 12 18 20.5 22 25 30 33 36 39 45 53 L2 (RTJ) mm 232 257 298 321 419 518 584 664 778 854 930 1010 1165 1372 in 9.13 10.13 11.75 12.63 16.5 20.38 23 26.13 30.63 33.63 36.63 39.75 45.89 54 H mm 153 165 195 213 272 342 495 580 625 720 790 840 1050 1150 in 6.02 6.5 7.68 8.39 10.7 13.5 19.5 22.85 24.6 28.35 31 33.1 41.34 45.3 Do(W) mm 400 400 600 850 1100 1500 *350 *350 *600 *600 *800 *800 *800 *800 in 15.74 15.74 23.62 33.46 43.3 59 13.8 13.8 23.6 23.6 31.5 31.5 31.5 31.5 RF(Kg) 18 27 47 80 118 200 365 530 740 1030 1320 1540 2600 3900 BW(Kg) 14 2 38 65 105 185 342 503 713 1000 1285 1498 2540 3825 *Worm Gear or Electric Actuator Operated Dervos Quality Checking System In Dervos, we control quality throughout the whole manufacturing process. Casting inspection: Though casting inspection, we can find out the problem of raw material, such as shoddy casting, unqualified wall thickness, chemical composition and so on, which ensure that you will not be cheated. Machining Inspection: On the one hand, we could ensure machining accuracy through this process. On the other hand, we can find out machining mistake as early as possible, to win more time for repairing and remaking Final Inspection: Final inspection activities include document and QC record review, visual examination, dimension check, pressure test, painting and packing check. You don’t need to come and inspect in person and all the documents could be provided as proof.
3/4" 150LB Y type strainer is made according to ASME B16.34 standard. The valve body is made of A350-LF2. It has the structural characteristics of Y-shaped, bolt cover, filter (100 microns). Its connection mode is RF.
DN100 PN40 butterfly valve is made according to EN 593 standard. The valve body is made of ASTM A216 WCB. It has the structural characteristics of three eccentric, bidirectional one to one pressure test. Its connection mode is EN1092-1 B. And it has turbine operation mode.
DN80 PN160 Forged Floating Ball Valve is made according to EN 12266 standard. The valve body is made of ASTM A105N. Its connection mode is LG. And it has Hand Wheel operation mode. Product Parameters Type Forged Floating Ball Valve Size DN80 Pressure PN160 Connection LG Operation Hand Wheel Body Material ASTM A105N Design Norm ISO 14313 Face to Face MFR’S End connection LG Test & Inspection Code EN 12266 Temperature -29 ~ 120°C Applicable Medium Water, Oil and Gas Features 1.Forged A105N carbon steel body ensures excellent mechanical strength and reliable performance in PN160 high-pressure applications. 2.Floating ball valve design tested to EN 12266 leakage grade LG provides tight shutoff and dependable sealing integrity. Technical Drawing Dimension Checking Pressure Testing
The 4 inch cryogenic ball valve, designed as per API609, has many parts equipped RPTFE --It has the lowest coefficient of friction and the best corrosion resistance of any known plastic material, so that the valve can handle quite extreme situations.
1” 1500LB Forged Steel Ball Check Valve is made according to API 602 ＆ ASME B16.34 standard. The valve body is made of A182 F316. It has the structural characteristics of Hemispherical Ball Check Valve. Its connection mode is BSP.
DN600 PN63 Cast Steel Gate Valve is made according to EN1984 standard. The valve body is made of A216 WCB+STL. It has the structural characteristics of Bolted Bonnet, Flexible Wedge, Rising Stem with Yoke. Its connection mode is EN1092-1 B1.
6" 150LB gate valve is made according to API 600 standard. The valve body is made of ASTM A217 WC6. It has the structural characteristics of bolt cover, elastic gate, rising stem, OS&Y, full bore, body valve seat. Its connection mode is RF (125~250AARH）. And it has hand wheel operation mode.
The DN150 PN10 unidirectional knife gate valve features a single piece, stainless steel body design provides tested performance in applications ranging from general purpose to severe media.
1" 800LB gate valve is made according to API602 standard. The valve body is made of F304L. It has the structural characteristics of bolt cover, rising stem, bracket and structural length of 311mm. Its connection mode is MNPT. And it has hand wheel operation mode.
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