Double Block Bleed Valve is a combination of a bleed valve with two block valves. This is a design structure that can allow for two way flow when necessary and to effectively control the liquid flow inside the system. There are different types of valves such as the Double Block Bleed Needle Valve which uses a needle for the block valves. The operation is by rotating the handle attached to the stem which is connected through a threaded bore to the needle. There can be a plug, needle, gate or knife at the end of the stem inside the body of the valve. The Double Block And Bleed Plug Valve uses a plug to sit on the seating and to close and open the valve gate.
Stainless Steel double block and bleed valve
A351 CF8 304 Block And Bleed Needle Valve
SS 316 Double Block And Bleed Steam Valve
The plug could be rubber or metallic depending on the material flowing inside the valve. The Double Block And Bleed Gate Valve is another type which uses gates to control the flow through the block valves. The gate is attached to the stem and the stem descends or ascends into and out of the body. The gate can be made up of steel or other high alloy materials. The Double Block And Bleed Knife Gate Valve uses a knife that is connected to the stem. The knife is essentially a gate that has a sharp edge. The knife gates are used to cut through high viscous liquids. The double block bleed valves are efficient and have less or no water hammer effects.
Size | 50NB — 600NB |
---|---|
Pressure | 150PS1 |
Temperature | 0 Deg C - 1200 Deg C. |
Body , Chest | Solid One piece casting of Cast Iron Fg 260, Cast Steel Gr WCB ,CF8,CF8M. |
Seat | Integral to Body, Soft, Optional. |
Gate | AISI SS 304,316,316L,317,317L |
Screw Spindle | AISI SS 410,304,316. |
Nut | Brass |
Yoke | Plate type of MS . |
Gland Follower | Cast Iron , Cast steel , Ductile Iron ,CF8,CF8M. |
Hand Wheel | Cast Iron , Cast steel , Ductile Iron |
Gland Packing | PTFE , PTFE Impregnated |
Ends | Lugged |
Port | STANDARD [Round], Optional V Port, Diamond Port,. |
Parameter | Standard |
Design | API 6D/ ISO 14313 |
Pressure-Temperature Rating | ASME B16.34 |
Face-to-Face | ASME B16.10 from 2” to 18”, Manufacturer standard for 20” and above |
End Flanges | ASME B16.5, ASME B16.47-Series A |
Actuator/ Gear Mounting Flange | ISO 5210 |
Pressure Testing | API 6D |
Fire Test | API 607/ ISO 10497 |
Fugitive Emission | ISO 15848, Part 1 |
Components | Materials |
Body | ASTM A216 Gr WCC + ENP |
Plug | ASTM A216 Gr WCC + ENP |
Segment | ASTM A395 Gr 60-40-18 |
Seal | Viton |
Bonnet | ASTM A216 Gr WCC |
Radial Bearing | Stainless Steel backed PTFE |
Packing | Flexible graphite |
O-Ring | Viton B |
Drain Plug | SS 410 |
Bottom Plate | ASTM A216 Gr WCC |
Gasket | Flexible graphite |
Gland Flange | ASTM A216 Gr WCB |
Outer Stem | ASTM A479 Type 410 |
Inner Stem | ASTM A479 Type 410 Condition 3 |
Stud | ASTM A193 Gr B7 |
Hex Nut | ASTM A194 Gr 2H |
Cavity Pressure Relief System | SS 316 |
ASME, Class | Size | A | B | C | CD** | ØF | |
NPS* | DN* | ||||||
150 | 2 | 50 | 178 | 455 | 150 | 85 | 49 |
3 | 80 | 203 | 470 | 175 | 100 | 74 | |
4 | 100 | 229 | 490 | 190 | 140 | 100 | |
6 | 150 | 267 | 640 | 225 | 200 | 150 | |
8 | 200 | 292 | 670 | 260 | 255 | 201 | |
10 | 250 | 330 | 710 | 290 | 340 | 252 | |
12 | 300 | 356 | 785 | 330 | 425 | 303 | |
14 | 350 | 381 | 800 | 380 | 465 | 334 | |
16 | 400 | 406 | 1075 | 410 | 535 | 385 | |
18 | 450 | 432 | 1100 | 440 | 590 | 436 | |
20 | 500 | 813 | 1140 | 495 | 670 | 487 | |
24 | 600 | 914 | 1215 | 570 | 820 | 589 | |
30 | 750 | 1524 | 1840 | 705 | 1035 | 735 |
ASME, Class | Size | A | B | C | CD** | ØF | |
NPS* | DN* | ||||||
300 | 2 | 50 | 216 | 455 | 150 | 85 | 49 |
3 | 80 | 283 | 470 | 175 | 100 | 74 | |
4 | 100 | 305 | 490 | 190 | 140 | 100 | |
6 | 150 | 403 | 640 | 225 | 200 | 150 | |
8 | 200 | 419 | 670 | 260 | 255 | 201 | |
10 | 250 | 457 | 710 | 270 | 330 | 252 | |
12 | 300 | 502 | 775 | 345 | 415 | 303 | |
14 | 350 | 762 | 825 | 395 | 465 | 334 | |
16 | 400 | 838 | 875 | 445 | 515 | 385 | |
18 | 450 | 914 | 925 | 495 | 565 | 436 | |
20 | 500 | 991 | 975 | 545 | 615 | 487 | |
24 | 600 | 1321 | 1025 | 600 | 665 | 589 | |
600 | 2 | 50 | 292 | 395 | 130 | 80 | 49 |
3 | 80 | 356 | 395 | 130 | 80 | 74 | |
4 | 100 | 432 | 495 | 185 | 105 | 100 | |
6 | 150 | 559 | 660 | 230 | 180 | 150 | |
8 | 200 | 660 | 690 | 280 | 250 | 201 | |
10 | 250 | 787 | 930 | 405 | 280 | 252 | |
12 | 300 | 838 | 970 | 435 | 350 | 303 |
Designator | Size |
1 | 9.5 mm (3/8”) |
2 | 14 mm (1/2”) |
3 | 19 mm (3/4”) |
4 | 25 mm (1”) |
5 | 38 mm (1 ½”) |
6 | 42 mm (1- 11/16”) |
7 | 50 mm (2”) |
Designator | Size |
8 | 1/2 |
12 | 3/4 |
16 | 1 |
24 | 1-1/2 |
32 | 2 |
48 | 3 |
Working pressure | PN 10 - PN 400 |
ASTM A351 CF8M Dbb Gate Valve
SS Double Block And Bleed Steam Valve
CF8M Stainless Steel Integral Double Block And Bleed Valve
Stainless Steel 304 1/2 npt Dbb Ball Valve
A351 CF8 Self Bleeding Ball Valve
Cast Iron Block And Bleed Valve
Maximum temperature | -400˚ to 850˚F |
Operating Temperature Range | PEEK Seat : -65℉(-54℃) to 400℉(205℃) PCTFE Seat : -22℉(-30℃) to 356℉(180℃) |
Maximum Operating Pressure | Class 2500(6000 psig) @ 100℉(38℃) |