The underground fully welded ball valve is a subcategory of steel fully welded ball valves. The body is made of various materials such as WCB (A105) and 304 stainless steel, with nominal diameters ranging from DN15 to DN400 and working pressures up to PN6.4 MPa. This product supports manual, pneumatic, and electric actuation methods and is certified to international and national standards such as API6D and ASTM. It is widely used in the oil and gas, chemical, and municipal construction industries, and is exported to many countries and regions in Europe, America, and Asia.
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underground fully welded ball valve Technical parameters
Design and manufacturing: GB/T 12237
The structural length:GB/T 12221
Connection forms:JB / T 79.1
Inspection and test:GB / T 26480
Caliber: 1/2″ ~ 48″ (DN15 ~ DN1200)
Pressure temporature level:GB / T 9131
Drive mode:Worm Gear
Pressure: PN1.6 MPa ~ PN42.0 MPa Class 150 ~ Class 2500
underground full welded ball valve Material for Main Part:
| No. | Name | Material | No. | Name | Material |
|---|---|---|---|---|---|
| 1 | Cap | ASTM A105 | 21 | Thrust bearings | PTFE |
| 2 | Body | ASTM A105 | 22 | Slide bearings | 304 + PTFE |
| 3 | Sphere | ASTM A105 + ENP | 23 | Support seat | ASTM A105 |
| 4 | Anti-static spring | Assembly | 24 | O-ring | VITON |
| 5 | Thrust bearings | PTFE | 25 | O-ring | VITON |
| 6 | Slide bearings | 304 + PTFE | 26 | Y-ring | VITON |
| 7 | Lower stem | ASTM A105 | 27 | Fire pad | SS304 + Graphite |
| 8 | Bottom cover | ASTM A105 | 28 | Filler | Graphite |
| 9 | Drain valve | ASTM A105 + ENP | 29 | Socket head cap screws | ASTM A193 B7 |
| 10 | O-ring | VITON | 30 | Socket head cap screws | ASTM A193 B7 |
| 11 | Fire pad | SS304 + Graphite | 31 | Valve stem | ASTM A182 F6a |
| 12 | Socket head cap screws | ASTM A193 B7 | 32 | Cylindrical pin | 35 |
| 13 | Footsteps | A3 | 33 | Studs | ASTM A193 B7 |
| 14 | Seat | PPL | 34 | Nut | ASTM A194 2H |
| 15 | Seat fire pad | SS304 + Graphite | 35 | Spring washer | 65Mn |
| 16 | Spring support seat | ASTM A105 | 36 | Land | ASTM A105 |
| 17 | Spring | 17-7PH | 37 | Flat key | 45 |
| 18 | O-ring | VITON | 38 | Turbine | ASTM A105-HZn |
| 19 | Seat support ring | ASTM A105 + ENP | 39 | Vent valve | ASTM A105-HZn |
| 20 | Slide bearings | 304 |
Custom-designed underground full welded ball valve drawings for a customer in the UAE
underground full welded ball valve Main Overall Dimension: (mm)
| DN | L (RF) | L (WE) | D1 | D2 | H1 | H2 | W |
|---|---|---|---|---|---|---|---|
| 150 | 403 | 457 | 219 | 273 | 246 | 193 | 280 |
| 200 | 502 | 521 | 273 | 351 | 285 | 238 | 320 |
| 250 | 568 | 560 | 325 | 426 | 323 | 278 | 320 |
| 300 | 648 | 635 | 377 | 508 | 365 | 315 | 400 |
| 350 | 762 | 762 | 426 | 580 | 410 | 370 | 400 |
| 400 | 838 | 838 | 480 | 675 | 457 | 425 | 450 |
| 450 | 914 | 914 | 530 | 740 | 495 | 465 | 450 |
| 500 | 991 | 991 | 630 | 805 | 540 | 495 | 500 |
| 600 | 1143 | 1143 | 735 | 975 | 640 | 580 | 500 |
| 700 | 1346 | 1346 | 830 | 1130 | 715 | 660 | 500 |
| 800 | 1524 | 1524 | 930 | 1270 | 785 | 730 | 500 |
| 900 | 1727 | 1727 | 1036 | 1425 | 860 | 820 | 800 |
| 1000 | 1900 | 1840 | 1236 | 1625 | 970 | 920 | 800 |
underground full welded ball valve Structural Features
Fully Welded Integrated Molding
The valve body is made of the same material as the pipeline (e.g., carbon steel, stainless steel), and is integrally welded, eliminating bolt connections and completely preventing external leakage risks. Compared to cast steel flange ball valves, this reduces three potential leakage points, solves defects such as sand holes and pores in cast steel valve bodies, and extends pipeline service life.
The valve body and pipeline material are the same, avoiding the risk of weld cracking due to uneven stress, and adapting to complex environments such as earthquake zones and vehicle traffic.
Extended Stem Design
The valve stem extends to the ground operating well, supporting ground operation. It eliminates the need for large valve wells, requiring only small shallow wells for maintenance, saving over 30% in construction costs.
Adjustable stem length adapts to different burial depths, suitable for diameters from DN15 to DN400.
High-Precision Ball and Sealing System
The ball is machined using a computer-controlled measuring instrument, ensuring extremely high precision and easy, interference-free operation.
The sealing ring is made of PTFE + 25% carbon fiber composite material, combined with a disc spring valve seat structure, to automatically compensate for temperature and pressure changes and ensure long-term zero leakage. It has passed the API 6D standard leakage test, demonstrating reliable sealing performance.
underground full welded ball valve Applications
Urban Gas Supply
Direct burial design saves urban space; combined with cathodic protection, it adapts to damp underground environments.
Applied to gas output pipelines, main lines, and branch supply pipelines, ensuring safe shut-off.
Heating Networks
Bidirectional sealing function solves pressure fluctuation problems in ring-shaped heating systems, reducing heat loss by more than 15%.
Suitable for opening and closing large heating equipment output pipelines, main lines, branch lines, and heat exchanger pipelines.
Petrochemical Industry
Achieves safe shut-off of highly corrosive media in reactors, storage tanks, and transmission pipelines; ATEX explosion-proof certified.
Industrial Equipment
Steel Plants: Various fluid pipelines, exhaust gas pipelines, gas and heat supply pipelines, and fuel supply pipelines.
Nuclear Power Plants and Thermal Power Plants: Enables rapid shutdown of high-temperature steam pipelines; response time ≤3 seconds.
Smelting Industry Blast Furnace Gas Pipelines: Withstands high-temperature conditions up to 1200℃, maintaining stable sealing performance.
underground fully welded ball valve factory
