Double Disc Gate ValvePRESSURE SEAL BONNET

2

BABCOCK VALVES

56 7A 7

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1 Available both in cast and forged steel, it has been designed to meet all the requirements of ASME, API and BS.The body-bonnet connection is made by a pressure seal gasket. Its pre-stress condition is achieved by means of bolts screwed to the bonnet flange. Ends are nor mally butt-welding although they can be also flanged on request.All bodies are provided with integrally cast bosses, located and sized in ac cordance with ASME B16.34, which allow the provision of drain and by-pass connections, supplied on request.Four internal guides keep the discs assembly in place, ena-bling operation of the valve with stem in both vertical and horizon tal positions.Two internal bosses in the lower part of the body are machined to create the mechanical stop of the lower wed ge.

2 Usually constructed in the same materials as the body, being designed so that the wall thickness always exceeds the re qui rement of API 600.A back seat (13) bush is fitted inside the bonnet lower cavity, to provide a closure when de valve is fully open. This permits the valve to be repacked while in service.The bonnet has a deep stuffing box in which packing rings are placed.Stuffing box is designed with sufficient space to allow lantern ring to be fitted.

3 Separate rigid yoke is provided to withs tand the thrust of the actuator. Large windows allow easy access and ventilation of the packing area. The yoke is connected to the body by a two piece clamping ring (193) an four clamp bolts. This connection is very solid and ena bles easy maintenance at site.The upper part of the yoke is suitably machined to house the yoke sleeve (11). The yoke is usually made of cast car bon steel regardless the type of body material, un less otherwise required by the client.

4 Constructed in stainless steel, ma chi ned from solid bar stock. The simple piece stem in threaded in the upper wedge.

A conical shoulder is also provided to ensure effective and tight seal backseat which allows the stuffing box to be repla ced with the valve in ser vi ce. The stem dimensions con form to API 600. Special care is taken in the machining of the stem, including the final po lis hing of the travelling area (con tact with the stuffing box). This allows a low-friction sur fa ce and a superior corrosion re sis tan ce.

They are supplied in two separate self aligning pieces, to en sure uniform pressure is effec ted during tightening of the packing.The upper part of the gland, which comes in contact with the gland flange, is spherical in shape.The gland flange is made of carbon steel but, upon request, materials can be supplied.

The gland studs are of the eyebolt type, which can be swung outwards for ease of gland re packing.

6 They are supplied in forged stain less steel, hardfaced with Stellite-6 (2 mm of minimum thic k ness). Seat rings are renewa ble, normally welded to the bo dy.Sealing contact surfaces, are lapped for a perfect tight seal. Controlled har dness differentials are maintained between the wed ge discs and the seat rings, as required by API 600 Std. 9 The two forged discs are made of the same material than the body, and the seating areas are hardfaced with 2 mm minimum thickness of Stellite-6.The important benefits of these re vol ving discs are explained widely in ano ther section of this catalogue.

11 Designed to permit removal from the bonnet or yoke while the valve is in service.The yoke bushing assembly is moun ted in ball bearings. It is normally made of cast aluminium bronze, having high re sis tance to wear and high melting point. Other materials such as Ni-resist can be supplied on request.

13 The back seat can be supplied as a threaded stainless steel bush, welded to the bonnet or of integral type. It can be hardfaced with Stellite-6 or orther materials as required.This seat allows the valve to be re pac ked under pressure.

The handwheel can be supplied either in cast construction of fabricated from steel tube.The handwheel is designed to allow easy operation of the valve. Other types of control are avai lable and, in some ca ses, are indispensable for a good operation, for instance:

· Chain wheel. · Gear operator. · Hammer handwheel. · Geared hammer hand wheel. · Electric actuator. · Electro-hydraulic actuator. · Pneumatic actuator.

17 The pressure seal gaskets are usually supplied of compressed graphite, bor dered on the upper and lower edges with braided filaments of carbon fiber.Gaskets can also be made in stainless steel.

Pac king is made of an ade qua te num ber of preformed rings.For general applicatios high grade graphite material is supplied, using compressed rings in the center and braided anti-extrusion rings on top and bo ttom. Graphite is selected of an approved quality.Other types of packing are also avai la ble for particular services.

The disc retainers are made of the same material than the bo dy. They are firmly connected to the upper wedge and keep the discs in place while allo wing their revol ving feature.The system of Stem, Dis cs, Upper Wedge and Disc re tai ners are crossed by a Wedge Pin (198) of Stainless Steel, con nec ted by two nuts (129 A) and cotter pints (198 A).

132 Ma de of a single piece covering the upper part of the pressure seal gasket. It is normally manufactured in the same ma-terial as the body.

133 It is made nor ma lly of the same ma terial as the body, and construc ted in four pie ces, called seg ments. The segments are si zed to mi ni mi ze the gap bet ween them.ntal ring supports all the forcers transmitted from the bonnet through the pres su re seal gasket and the spacer ring. It is calculated to withs tand all the force without crac king.

134 De sig ned su ffi cien tly re sis tant to withs tand the for ces trans mit ted by the bon net screws (111).The bonnet retainer is normally ma de of the same material as the body, but it can be constructed in any other material on re quest. It is machined to ma t ch exactly with the body, what gua rantees a perfect alig nment of the unit.

193 The connection between body and yoke is created by means of a bipartite clamping ring. The in ternal connection between the clamp, body and yoke is co ni cal, assuring a per fect tig hte ning.

7 & 7A

The wedges ares constructed in forged or cast steel of the same material than the body. The contact surfaces are hardfaced with Stellite-6. The spe cial geometry of these wedges has been de sig ned so that they cannot be ca me disengaged while they are sliding. The wedges impart thrust to the discs which move towards the seat rings (6) assuring a tight seal.Two wedge springs (56) are loca ted in the cavities between the upper and lower wedges, in or der to ab sorb the inertial forces and per mit a soft contact of the sliding inclined part of the wed ges.

4

Notes:

acc. to customer requirements.

BABCOCK VALVES

PRESSURE SEAL BONNET

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SIZE 2” 2 I/2” 3” 4” 6” 8” 10” 12” 14” 16” 18” 20” 24” 26” 28” 32” 36”

A 177,8 215,9 254 304,8 457,2 584,2 711,2 812,8 889 990,5 1092,2 1193,8 1397 1447 1549 1778 2082

F (RF) 292,1 330,2 355,6 431,8 558,8 660,4 787,4 838,2 889 990,5 092,2 1193,8 1397 1447 1549 1778 2082

J (RJ) 295,1 333,2 358,6 434,8 561,8 663,4 790,4 841,2 892 993,6 1095,2 1200,1 1406,6 1456,6 1558,6 1787,6 2091,5

B 500 533 686 813 1067 1168 1397 1626 1753 1981 2108 2489 2794 2990 3150 3550 3800

øC 203 203 254 305 355 510 510 610 610 610 915 915 915 915 915 915 915

OPERATION HANDWHEEL GEAR

WEIGHT 34,5 36,8 55,2 89,7 190,9 316,25 499,1 690 1016,6 1353,55 1756,05 2754,25 3920,35 4542,5 5462,5 10292,5 9401,25

Cv 273 375 550 1025 2375 4225 6625 9850 12025 15900 20100 24900 36525 46300 54038 69848 93685

SIZE 2” 2 I/2” 3” 4” 6” 8” 10” 12” 14” 16” 18” 20” 24” 25” 30” 36”

A 215,9 304,8 304,8 355,6 508 660,4 787,4 914,4 990,6 1092,2 1219,2 1320,8 1549,4 1574 1778 2032

F (RF) 368,3 419,1 381 457,2 609,6 736,6 838,2 965,2 1028,7 1130,3 1219,2 1320,8 1549,4 1574 1778 2032

J (RJ) 371,3 422,1 384 460,2 612,6 739,6 841,2 968,2 1038,3 1139,9 1231,9 1333,5 1568,4 1593,5 1797 2051

B 530 638 638 831 1072 1186 1500 1540 1725 1836 2220 2412 2650 2880 4060 4885

øC 254 305 305 381 610 686 800 1000 750 750 1000 750 1000 750 1000 1000

WEIGHT 74,75 77,05 70,15 101,2 251,85 441,6 763,6 977,5 1702 2162 3174 4128,5 6152,5 6532 10350 15525

OPERATION HANDWHEEL GEAR

Cv 218 300 500 950 2175 3825 6125 8850 10875 14325 18300 22875 33275 36678 50198 87027

SIZE 2” 2 I/2” 3” 4” 6” 8” 10” 12” 14” 16” 18” 20” 24” 28” 32” 36”

A 215,9 254 304,8 406,4 558,8 711,2 863,5 990,6 1066,8 1193,8 1346 1473,2 1752,6 2209 2413 2565

F (RF) 368,3 419,1 469,9 546,1 704,8 831,8 990,6 1130,3 1257,3 1384,3 1536,7 1663,7 1943,1 2209 2413 2565

J (RJ) 371,3 422,1 472,9 549,1 711,1 841,4 1000,2 1146 1276,3 1406,6 1559 1686 1971,5 2228 2432 2584

B 530 758 758 861 1002 1080 1490 1530 1850 1960 1950 2385 2795 3405 4150 4950

øC 254 381 381 457 686 686 600 750 900 750 600 900 900 900 900 900

OPERATION HANDWHEEL GEAR

WEIGHT 74,75 83,95 83,95 184 379,5 650,9 1076,4 1472 2357,5 2777,25 4268,8 5175 8222,5 11097,5 15237,5 18572,5

Cv 218 300 450 817 1875 3275 5250 7525 9175 12150 15500 19600 28775 42572 55027 73806

SIZE 2” 2 I/2” 3” 4” 6” 8” 10” 12” 14” 16” 18” 20” 24” 28” 32” 36”

A 279,4 330,2 368,3 457,2 609,6 762 914,4 1041,4 1117,6 1244,6 1397 1397 1625 1905 2184 2413

F (RF) 450,8 508 577,8 673,1 914,4 1022,3 1270 1422,4

J (RJ) 453,8 514,3 584,1 682,7 927,1 1038 1292,3 1444,7

B 515 736 736 840 1000 1220 1484 1680 1842 1988 2250 2510 2950 3450 4150 4900

øC 381 457 457 534 800 600 750 600 900 600 900 900 900 900 900 900

WEIGHT 138 158,7 167,9 241,5 455,4 787,75 1524,9 2375,9 3082 3737,5 5002,5 6532 9545 13225 20355 24150

OPERATION HANDWHEEL GEAR

Cv 145 200 300 500 1250 2200 3600 5200 6400 8500 10875 13325 19725 29183 37720 50592

SIZE 2” 2 I/2” 3” 4” 6” 8” 10” 12” 14” 16” 18” 20” 22” 24” 28” 32”

A 514,3 514,3 432

F (RF) – – –

J (RJ) – – –

B 806 806 806

øC 457 457 457

WEIGHT 480,7 478,4 584,2

OPERATION HANDWHEEL

Cv 109 163 272

ASME CLASS 4500

ASME CLASS 2500

ASME CLASS 1500

ASME CLASS 900

ASME CLASS 600

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BABCOCK VALVES

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STANDARD MATERIALS

PART. Denomination CARBON STEEL ALLOY STEEL STAINLESS STEEL

1 BODY ASTM A 216 WCB ASTM A 217 WC9 ASTM A 351 CF8M

2 BONNET ASTM A 105 ASTM A 182 F22 ASTM A 182 F316

3 YOKE ASTM A 216 WCB ASTM A 216 WCB ASTM A 216 WCB

4 STEM ASTM A 182 F6A ASTM A 182 F6A ASTM A 182 F316

5 GLAND ASTM A 182 F6A ASTM A 182 F6A ASTM A 182 F316

6 SEAT RING ASTM A105+STELLITE ASTM A182F22+STELLITE ASTM A351CF8M+STELLITE

7 UPPER WEDGE ASTM A216WCB+STELLITE ASTM A217WC9+STELLITE ASTM A351CF8M+STELLITE

7A LOWER WEDGE ASTM A216WCB+STELLITE ASTM A217WC9+STELLITE ASTM A351CF8M+STELLITE

9 DISC ASTM A105+STELLITE ASTM A182F22+STELLITE ASTM A351CF8M+STELLITE

11 YOKE SLEEVE ALUMINIUM-BRONZE ALUMINIUM-BRONZE ALUMINIUM-BRONZE

13 BACK SEAT ASTM A105+STELLITE ASTM A182F22+STELLITE ASTM A182F316+STELLITE

15 HANDWHEEL CARBON STEEL CARBON STEEL CARBON STEEL

17 PRESSURE SEAL GASKET COMPRESSED & BRAIDED GRAPHITE COMPRESSED & BRAIDED GRAPHITE COMPRESSED & BRAIDED GRAPHITE

20 SLEEVE NUT CARBON STEEL CARBON STEEL CARBON STEEL

22 GLAND NUT ASTM A 194 2H ASTM A 194 2H ASTM A 194 2H

24 YOKE FLANGE CARBON STEEL CARBON STEEL CARBON STEEL

56 WEDGE SPRING AISI 302 AISI 302 AISI 302

68 INTERMEDIATE PACKING GRAPHITE GRAPHITE GRAPHITE

68A END PACKING BRAIDED GRAPHITE BRAIDED GRAPHITE BRAIDED GRAPHITE

75 BEARING COMMERCIAL COMMERCIAL COMMERCIAL

80 DISC RETAINER ASTM A515Gr70 ASTM A182F6A ASTM A182 F316

87 SPRING WASHER AISI 304 AISI 304 AISI 304

111 YOKE FLANGE CAP SCREW AISI 4140 AISI 4140 AISI 4140

111A BONNET CAP SCREW AISI 4140 AISI 4140 AISI 4140

118 GLAND RETAINER CAP SCREW AISI 4140 AISI 4140 AISI 4140

125 GLAND FLANGE ASTM A 515 Gr 70 ASTM A 515 Gr 70 ASTM A 515 Gr 70

127 YOKE CLAMP STUD ASTM A 193 B7 ASTM A 193 B7 ASTM A 193 B7

128 GLAND BOLT ASTM A 193 B7 ASTM A 193 B7 ASTM A 193 B7

129 YOKE CLAMP NUT ASTM A 194 2H ASTM A 194 2H ASTM A 194 2H

129A DISC RETAINER NUT ASTM A 194 2H ASTM A 194 2H ASTM A 194 2H

132 SPACER RING ASTM A 105 ASTM A 182 F22 ASTM A 182 F316

133 GASKET RETAINER ASTM A 105 ASTM A 182 F22 ASTM A 182 F316

134 BONNET RETAINER ASTM A 515 Gr 70 ASTM A 515 Gr 70 ASTM A 515 Gr 70

193 YOKE CLAMP ASTM A 515 Gr 70 ASTM A 515 Gr 70 ASTM A 515 Gr 70

194 GLAND RETAINER ASTM A 515 Gr 70 ASTM A 515 Gr 70 ASTM A 515 Gr 70

195 GREASE FITTING COMMERCIAL COMMERCIAL COMMERCIAL

198 WEDGE PIN AISI 431 AISI 431 AISI 431

198A COTTER PIN STAINLESS STEEL STAINLESS STEEL STAINLESS STEEL

Other materials are available on request.

The trim components are:

8

The Double Disc Gate Valve has been desig ned to assure reliable operation under the most severe service conditions. Due to the special configuration and geo me try of the upper wedge inclined face, any pos sibility of locking the disc in closed position is eliminated, even when closed quickly or subjected to severe thermal tran sients.

The wedge assembly is designed to impart sufficient thrust to each disc to maintain low pressure sealing. As the differential pressure across the disc increases, the seating load also increases, thus providing a tight seal throughout the entire range of operating differential pressures. Since the discs are independent of each other and the design is symmetrical, positive sealing can be main tained in either direction.

The four piece double disc wedge assembly can neither be incorrectly assembled nor become disengaged while in service. No special fitting at site is required for maintenance. The repair of minor seat or disc damage is greatly simplified because the seats and discs can be lapped in de-pen den tly of each other. Disassembly and ma in te nance can be accomplished without special tools or elaborate rigging.

BPE’s Double Disc Wedge system permits rapid closure without seat distortion. Internal moving parts decelerate independently of each other with the result that inertial forces are dissipated in a series of impacts over a period of time. The largest of these is trans mitted directly to the bottom of the valve body on a non-sealing surface. Forces trans mitted directly to the seats are a small per centage of the total inertial forces. This is a distinct advantage over valve designs in which the total inertial force is absorbed directly by the seating surface.

The tight seal is guaranteed even when the valve seats have become out of parallel due to body distortion, due to the uniform distribution of the sealing pressures allowed by the exclusive wedge design.

The incorporation of a unique revolving disc feature assures maximum seat life. The two independent discs, during each closing stroke and immediately prior to the disc seating, rotate a few degrees in the plane of the seats. This rotating action forces the disc to seat in a different position on each stroke, equalizing wear on the seats and the discs. This movement of the discs creates a lapping effect whenever the valve is operated, removing particles from the sealing surfaces before they can become wedged between the seats and the disc and cause damage.

BABCOCK VALVES

TECHNICAL ADVANTAGES OF THE DOUBLE DISC WEDGE ASSEMBLY

/9/ 9

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The parallel slide gate valves are an alternative option of double disc valves, having single wedge instead of double wedge. The horizontal spring keeps the discs in permanent contact with the seat rings, assuring tight seal.

Code 86: Follower eye for very laminar flow is available on request. It avoids any turbulences and mi ni mizes the pres sure drop.

BABCOCK VALVES

PARALLEL SLIDE GATE VALVE

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Exploded view of the parallel slide system, showing all the parts involved in this assembly.

BABCOCK VALVES, S.L. P.E. Abra Industrial, Parcela 1.5.6 48530 Ortuella – Bizkaia (SPAIN)

Phone: + 34 94 4536423Fax: + 34 94 4535739

Email ID: info@babcockvalves.comwww.babcockvalves.com