YRWY LOW-OFF VLVS STLSS, HRDST ND UNIT TNDM Designed for blow-off service in boiler systems with pressures of 36 psig. FTURS GNRL LICTION low-off service in boiler systems to remove dirt, sediment and scale as well as maintain boiler level surge. TCHNICL DT Size range: NS, ¼, ½, 2, 2½ [DN 25, 32, 40, 50, 65] ressure Rating: Up to 36 psi Connection: Flanged, Socketweld, uttweld Materials: Cast Iron, Carbon Steel Designed according SM section, SM 3., SM 6.34. For boiler systems up to 36 psig. Rugged construction to withstand high pressure and high velocities. xcellent resistance to cleaning acids and wear caused by precipitated solids. Seatless valves No Seat - will not score or plug with dirt - will not leak Live-loaded packing - will not leak after packing Slow opening -will not rapidly drain boiler drum Unit tandem valves Combination of hardseat and seatless valves in a single body - eliminates pipe joints - reduces potential leaks - fits into a confined space Hardseat valves Stellite seat faces - resists wear - provides long service life merson.com/finalcontrol 7 merson. ll Rights Reserved. VCTDS-00404-N 5/06
YRWY LOW-OFF VLVS STLSS, HRDST ND UNIT TNDM GNRL DSCRITION TY STLSS LOW-OFF VLV asic requirements for the design and use of blow-off valves are established by the SM ower oiler Code, Section l. The general form of a valve, the materials of its construction, allowable boiler pressures, and the installation of the valve are all determined by the code. Yarway blow-off valves are designed in conformance with all code requirements (SM Section l, SM 3., SM 6.34). ecause the primary purpose of a blow-off valve is removal of dirt, sediment and scale, the boiler code requires that valves which have dams or pockets in which sediment can accumulate cannot be used in blow-off service. This means that ordinary globe valves cannot be used as blow-off valves. Yarway valves are especially designed for the punishment of blow-off service in boiler systems with pressures of 36 psi. The rugged construction of these valves can successfully withstand the combination of problems inherent in the service - a service in which high pressures result in high velocities which can cause wire drawing and cavitation of metal surfaces. The valves must also withstand the corrosive environment created by acid cleaning of boilers, and the potential wear problems caused by precipitated solids. all bearing yoke for easy operation of handwheel. Long stroke length with threaded stem helps prevent water hammer, which occurs when valve is opened or closed too quickly. Shoulder on plunger transmits force, in the closed position, through glands to packing rings. Nitralloy plunger tube resists erosion, high temperatures and sudden shocks. Seatless, sliding design provides polishing action that lengthens life of packing rings. Open yoke shows position of plunger in body. Dual guide lugs provide proper alignment. Compression springs maintain continuous pressure on packing rings to keep valve tight regardless of plunger position. The valves are also helpful in maintaining boiler level surge within desirable limits during quick startup of high pressure systems. Two broad categories of Yarway blow-off valves are available; those that operate on a sliding principle and those that operate on a seat-anddisc principle. 2
YRWY LOW-OFF VLVS STLSS, HRDST ND UNIT TNDM Flange and drilling data common to all Yarway valve designs are shown below. ll dimensions are consistent with SM standards and supplied as listed unless otherwise specified. LOW-OFF VLV FLNG DT - FLNG DIMNSIONS Diameter Thickness Diameter of raised face Size NS Class 250-600 Class 500 Class 2500 Class 250-300 Class 400-600 Class 500 Class 2500 Class 250 Class 300-2500 4⅞ 5⅞ 6¼ /6 5/6 [2] ⅜ ⅝ 2 /6 2 ½ 6⅛ 7 8 3/6 ⅛ ½ 2 3 9 /6 2⅞ 2 6½ 8½ 9¼ ⅞ ¼ ¾ 2¼ 4 3 /6 3⅝ 2½ 7½ 9⅝ 0½ ⅜ ⅞ 2½ 4 5 /6 4⅛ DRILLING DT Size (NS) No. of holes [3] Class 250-600 Class 500 Class 2500 Class 250-600 Class 500 Class 2500 Diameter olt circle diameter 4 ¾ 3½ 4 4¼ ½ 4 ⅞ ⅛ ¼ 4½ 4⅜ 5¾ 2 8 ¾ ⅛ 5 6½ 6¾ 2½ 8 ⅞ ⅛ ¼ 5⅞ 7½ 7¾ NOTS:. Includes /6 raised face 250-400 psi valves, ¼ raised face 600-2500 psi. 2. 600 psi only, no 400 psi valve available. 3. olt holes straddle center lines. 3
YRWY LOW-OFF VLVS STLSS, HRDST ND UNIT TNDM STLSS VLVS FOR RSSURS TO 935 SI - CLSS 250 TO 600 The seatless blow-off valve is a sliding plunger type, opened and closed by means of a handwheel and non-rising stem, and sealed against leakage by packing rings above and below the ports. This valve is provided with heavy coil compression springs under the yoke nuts. Designed to help prevent leaking when the valve is open, yoke nuts are screwed down evenly and tightly placing compression on the springs and the packing rings. mple flow area is provided in the hollow plunger; absence of projections or pockets prevents accumulation of scale and sediment that can impede flow and shorten the life of the valve. nnular space in the body permits pressure to surround the plunger, making the valve a fully balanced unit easy to operate at high pressures. For complete protection of the packing, the valve has a long-stroke plunger so that the packing is never exposed to the mainstream flow. The gland and plunger have double inlet ports to balance flow pressures. This valve is available in angle or straightway styles, cast iron or steel construction, and flanged ends. Operation When the valve is open (plunger raised), discharge occurs through double ports in the lower gland and plunger. The slotted plunger head slides on guides in the valve yoke, preventing rotation of the plunger. stop screw keeps the lower gland in alignment. The yoke permits visual indication of the position of the plunger within the valve body. Upon closing, the shoulder on the plunger exerts a thrust force compressing the packing rings above and below the port in the body. final hard turn of the handwheel gives additional compression of the packing around the plunger, ensuring drop tight shutoff. nd connections Flange dimensions per SM 6.5 ctuation Manual handwheel only. 4
YRWY LOW-OFF VLVS STLSS, HRDST ND UNIT TNDM Standard options cid wash trim:. Standard upper gland is replaced with nickel plated steel upper gland. 2. Standard lower gland is replaced with Niresist lower gland. 3. Standard plunger is replaced with nickel plated nitralloy plunger. Stop screw with lubrication fitting. Caution plate for tandem sets. Special flanges only when dimensions are within standard flange maximum metal conditions. How to specify To specify seatless valves for nominal pressures to 600 psi, use figure number shown. Describe as long stroke, balanced sliding plunger type seatless valve. How to order Order by stating: a. Size b. Figure number c. asic pressure rating d. Connections - flanged e. ngle or straightway style 2 7 6 4 5 3 2 7 6 4 5 3 STLSS VLVS FOR RSSURS TO 935 SI - CLSS 250 TO 600 MTRILS OF CONSTRUCTION (pressure containing envelope) Valve type Class body 2 yoke 3 and 4 packing rings 5 and 6 glands 7 plunger 250 Cast iron STM 26 Cast iron STM 395 Graphite, SS filled TF, Hard brass 35 Nitralloy Grade H Class 60-40-8 rass or SS support ring [] lloy 3 300 Cast steel SM S26 Cast steel SM S26 Graphite, SS filled TF, Hard brass 35 Nitralloy Grade H Grade WC Grade WC rass or SS support ring [] lloy 3 C 600 Cast steel SM S26 Cast steel SM S26 Graphite, SS filled TF, Low Carbon steel Nitralloy Grade H Grade WC Grade WC SS support ring NOT:. 36 SS for acid wash trim. 5
YRWY LOW-OFF VLVS STLSS, HRDST ND UNIT TNDM STLSS VLVS FOR RSSURS TO 935 SI - CLSS 250 TO 600 FIGUR 3482-R ND 3486-R TY FIGUR 3484-R ND 3488-R TY S dia. S dia. /6 L R 45 F D F D C M /6 FIGUR 390-R TY C S FIGUR 392-R TY C S R L 45 F D /4 F D C M /4 DIMNSIONS ND WIGHTS ress. low-off Figure number Size Dimensions Wt. rating class (max. psi) ngle Straight- way NS C D F L M R S C v (lb.) 250 0 3482-R 3484-R 4 6 0¼ 4⅞ /6 2 /6 8¼ 7¼ 4 3 /6 8⅜ 24 30 250 0 3482-R 3484-R ½ 4½ 4½ 6⅛ 3 /6 3 9 /6 8¼ 8½ ½ 6 8⅜ 30 38 250 0 3482-R 3484-R 2 5 5 2 6½ ⅞ 4 3 /6 9⅜ 9⅞ 2 7 9⅜ 58 55 250 0 3482-R 3484-R 2½ 5¾ 5¾ 3½ 7½ 4 5 /6 2⅞ 22⅛ 2½ 9½ 73 85 300 490 3486-R 3488-R 3 5 /6 5⅝ 9⅞ 4⅞ /6 2 7¾ 6⅞ 4 3 /6 8⅜ 27 38 300 490 3486-R 3488-R ½ 4 7 /6 4 9 /6 6⅛ 3 /6 2⅞ 8 /6 8½ ½ 5⅞ 8⅜ 30 45 300 490 3486-R 3488-R 2 5 5¼ 2 6½ ⅞ 3⅝ 9 9 /6 9 5 /6 2 7⅜ 9⅜ 58 65 300 490 3486-R 3488-R 2½ 5¾ 6 3½ 7½ 4⅛ 22⅛ 22⅛ 2½ 9½ 79 90 600 935 390-R 392-R ½ 4½ 8¼ 3 6⅛ ⅛ 2⅞ 22⅞ 22½ ½ 9⅝ 8⅜ 30 53 600 935 390-R 392-R 2 5¼ 9¼ 5 6½ ¼ 3⅝ 25¼ 22 5 /6 2 22 5 /6 9⅜ 59 75 600 935 390-R 392-R 2½ 5¾ 9½ 7 7½ ⅜ 4⅛ 27¾ 28½ 2½ 25⅜ 79 05 6
YRWY LOW-OFF VLVS STLSS, HRDST ND UNIT TNDM HRDST VLVS FOR RSSURS TO 2455 SI - CLSS 600 ND 500 The hardseat valve has a seat and disc design with flow entering under the seat. It is opened and closed by means of a handwheel and threaded rising stem. The stuffing box bushing and threaded yoke bushing provide a simple, sturdy guide for the stem. This valve has been designed with thick Stellite facings on the disc and seat to provide the hard wearing, anti-galling surfaces characteristic of Stellite. Operation Hardseat valves are available in angle or straightway styles, socketweld or flanged end connections with manual or electric motor actuation. Usual installation of this valve allows the flow to enter below the seat. s the valve is opened, the lip on the end of the disc restricts the flow until the beveled edge or seating surface of the disc is well away from the seat. This minimizes wiredrawing and protects the sealing faces. The valve should be opened rapidly and fully to help increase the life of the internal parts. Tandem usage ny two Yarway hardseat valves may be used in tandem for pressures to 2455 psi. The valve nearest the boiler is used as the blowing valve (opened last and closed first) and the valve farthest from the boiler is the sealing valve (opened first and closed last). For pressures to 935 psi, hardseat valves may be used in tandem with Yarway Type C seatless valves. How to specify For single valves, describe as seat and disc type hardseat valve. Use size and figure number shown. For tandem valves (pressures to 2455 psi), describe as: blow-off valves shall consist of one angle and one straightway (or two angle or two straightway) seat and disc type hardseat valves, installed in tandem arrangement, to conform with requirements of SM oiler Code and suitable for basic pressure rating of psi. How to order Order by stating: a. Size b. Figure number c. asic pressure rating d. Connections - flanged and socketweld for 600 class valves; socketweld for 500 class valves. s an option, buttweld ends are available for 2 and 2½ 500 class valves only. e. ngle or straightway style 7
YRWY LOW-OFF VLVS STLSS, HRDST ND UNIT TNDM HRDST VLVS FOR RSSURS TO 2455 SI - CLSS 600 ND 500 2 3 9 8 0 4 6 5 7 6 7 3 2 5 4 MTRILS OF CONSTRUCTION Figures 6909, 69, 692, 6929-C, 693-C Figures 6929, 693 Item art Material Specifications Material Specifications ody Steel SM S-26 WC Steel SM S-05 2 Nozzle with integral Steel with integral Steel with integral Seat Stellited face SM S-26 WC Stellited face SM S-05 3 Gland Steel SM S-26 WC [2] Steel SM S-05 4 Split gland bushing Naval brass [2] - Stainless steel ISI 46 5 Disc Steel with stellited seating face SM S-82 Grade F Steel with stellited seating face SM S-82 Grade F 6 Disc nut Stainless steel ISI 40 2 Stainless steel ISI 40 2 7 Stuffing box bushing Nickel alloy Ni-Resist No. Nickel alloy Ni-Resist No. 8 Yoke bushing Naval brass Silicon brass -37 lloy 694 9 Stem Stainless steel STM -582 Type 46 Stainless steel STM -582 Type 46 0 Handwheel Cast iron STM -47 Gr. 3250 Cast iron STM -47 Gr. 3250 2 Hex nut Steel SM S-94 Gr. 2H Steel SM S-94 Gr. 2H 3 Hex nut Steel SM S-94 Gr. 2H Steel SM S-94 Gr. 2H 4 olt Steel SM S-93 Gr. 7 Steel SM S-93 Gr. 7 5 Disc insert Stainless steel (heat treated) ISI 40 Stainless steel (heat treated) ISI 40 6 acking Flexible graphite - Flexible graphite - 7 Sleeve insert [3] Steel - Steel - NOTS:. ½ 6929 and 693 only. 2 and 2½ 6929-C and 693-C body and nozzle are cast SM S26 WC ( C in Figure Number designates cast material); gland SM S27 WC. 2. ½ valve gland material is SM S8 Gr. II; split gland bushing and disc nut material is ISI 46. 3. 2 and 2½ valve only. 8
YRWY LOW-OFF VLVS STLSS, HRDST ND UNIT TNDM HRDST VLVS FOR RSSURS TO 2455 SI - CLSS 600 ND 500 FIGUR 6909-C FIGUR 690-C FIGUR 69-C H dia. H dia. M - open M - open K - open T - open H dia. ¼ D F D 45 D F F Direction of flow C L - open FIGUR 692-C FIGUR 6929 ND 6929-C FIGUR 693 ND 693-C K - open T - open H dia. T - open H dia. K - Open T - Open H dia. 45 F D 45 D 45 D C ¼ F C F L - open M - open L - open DIMNSIONS ND WIGHTS ress. low-off Figure number Size Dimensions Wt. class rating (max. psi) ngle Straight- way NS C D F H K L M T C v (lb.) 600 935 6909-C 69-C ½ 3¼ 3⅜ 8¼ 3.92 ½ ½ 2⅞ 6⅛ /6 ½ 2⅜ 4 25 600 935 6909-C 69-C 2 3⅝ 3¾ 9 3½ 2.4 ⅝ ½ 4¾ 8⅜ 3⅜ 2 5 96 44 600 935 6909-C 69-C 2½ 4 4⅜ 0½ 4 2.9 ⅝ ½ 6⅜ ½ 5½ 2½ 7⅜ 25 75 600 935 690-C 692-C ½ 4¾ 4½ 2 6⅛ ⅛ 2⅞ ½ 2⅞ 7¼ /6 ½ 2⅜ 4 36 600 935 690-C 692-C 2 5¾ 5 4 6½ ¼ 3⅝ ½ 4¾ 9⅝ 3⅜ 2 5 96 55 600 935 690-C 692-C 2½ 6½ 5⅞ 6 7½ ⅜ 4⅛ ½ 6⅜ 2¾ 5½ 2½ 7⅜ 25 85 500 2455 6929 693 ½ 5 9 /6 3 7 /6 9 2⅝.92 ½ ½ 6 9½ 6 ⅜ 7 4 33 500 2455 6929-C 693-C 2 5⅜ 3⅞ 9¼ 4⅛ 2.4 ⅝ 3½ 7 /6 2 7 /6 7 /6 5 /6 8⅛ 95 60 500 2455 6929-C 693-C 2½ 5⅜ 3⅞ 9¼ 4⅛ 2.9 ⅝ 3½ 7 /6 2 7 /6 7 /6 2⅛ 8⅛ 95 60 9
YRWY LOW-OFF VLVS STLSS, HRDST ND UNIT TNDM UNIT TNDM VLVS FOR RSSURS TO 36 SI - CLSS 300 TO 2500 The Yarway unit tandem valve features a one-piece steel block which serves as a common body for both blowing and sealing valves. This construction eliminates interconnecting welds, or bolts and gaskets where flanged valves are required, and makes the unit tandem a compact design. For valves with basic pressure rating to 600 psi (medium pressure unit tandem), the inlet valve is a hardseat type and the discharge valve is of the seatless type. For basic pressure ratings above 600 to 2500 psi, both inlet and discharge valves are hardseat type. ½ 6978-6978 LFT HND lowing valve Sealing valve ll features of the Yarway single valves are contained in the unit tandem design with the additional advantage of a one-piece, heavy duty construction. These valves are available in right-hand or left-hand body assemblies, carbon steel (SM S-05), socketweld or flanged end connections. ll hardseat unit tandem valves include acid wash trim. In hardseat seatless unit tandem valves, acid wash trim is optional. The hardseat valve of any unit tandem can be equipped with an electric motor actuator (230/460-volt, three-phase, 60-Hertz). From boiler Special voltage and standard actuator accessories are available. To drain How to specify To specify unit tandem valves use size and figure numbers shown. Describe as: valve assembly shall consist of one seat and disc type hardseat valve and one balanced, sliding plunger type seatless valve (or two seat and disc hardseat valves) assembled in tandem arrangement as part of one common body conforming with requirements of SM oiler Code and suitable for pressure rating of psi. When motor actuation is desired, describe as: with electric motor actuation (230/460-volt, three-phase, 60-Hertz). How to order Order by stating: a. Size b. Figure number c. asic pressure rating d. Connectors - flanged or socketwelding ends (if buttwelding ends are required, include description of profile) e. Hand: right-hand or left-hand f. Trim: standard or acid wash How to hand unit tandem valves ecause the construction and installation of a unit tandem valve is inherently off-center with respect to the centerline of the boiler outlet, opening and closing of the valve can become difficult if operating space is inadequate on the side of the blowing valve. lowdown valve handwheel lowdown valve handwheel Therefore, the practice of handing a valve has become part of its specification. This is essentially a statement of planned position for the valve, to the left-hand or right-hand of the centerline of the boiler outlet, by specifying the location of the sealing valve when facing the handwheel of the blowing valve (next to boiler). The drawing shown should help you to hand or orient your valves correctly. Sealing valve Specify location (right or left) of sealing valve when facing handwheel of next-to boiler hardseat blowing valve. Right hand Left hand 0
YRWY LOW-OFF VLVS STLSS, HRDST ND UNIT TNDM MTRILS OF CONSTRUCTION (see pages 8 - for drawing references) Item art Material Specification ody Carbon steel - 0.35% max. C (Stellited seat) SM S-05 3 Spring Steel S 650 4 Stud Steel SM S 93 Gr. 7 5 xtension lever Malleable iron - 6 Nozzle Forged steel - 0.35% max. C SM S-05 7 Yoke Steel SM S-05 9 Gland Steel STM -8 Grade II [] Disc Steel (stellited) SM S-82 Grade F 2 Split gland bushing Stainless steel Type 46 2 22 Disc nut Stainless steel Type 40 23 Stuffing box bushing Nickel alloy Ni-Resist No. 24 Yoke bushing ronze STM -37 lloy 694 2 25 Stem Stainless steel STM -582 Type 46 26 olt Stainless steel STM -93-6 3 27 Handwheel Cast iron STM -48 28 acking Flexible graphite (carbon braid end rings) - 3 Disc insert Stainless steel (heat treated) ISI 40 NOTS:. 600 psi and lower rated valve; SM S-26 Gr. WC. 2. 600 psi and lower rated valve; Naval rass. 3. 600 psi and lower rated valve; SM S-93 7. DIMNSIONS ND WIGHTS (see pages 8 - for drawing references) ress. low-off Size Dimensions Stem rating class (max. psi) Figure no. NS C D G H K (closed) L (closed) M rise C v Wt. (lb.) 300 490 3947-3927 [] 5 3 /6 5½ 3 2⅜.33 8⅜ ½ 0⅝ 6 7 /6 8⅜ 3 /32 5/6 7 50 300 490 3947-3927 [] ½ 5 3 /6 5½ 3 3⅛.92 8⅜ ½ 0⅝ 6 7 /6 8⅜ ½ 5/6 22 65 300 490 3947-3927 [] 2 6 3 /6 5 5 /6 3 3 /6 3⅜ 2.4 9⅜ ⅝ 2 5 /6 8½ 9⅜ 5 /6 3 /6 38 08 300 490 3947-3927 [] 2½ 7 /6 7 /6 4⅛ 4 2.9 ⅝ 4 /6 2¾ 2½ ¼ 47 50 300 490 3948-3928 [] 4¾ 7⅛ 3 4⅞ /6 8⅜ - 0⅝ 5⅜ 8⅜ 5/6 7 55 300 490 3948-3928 [] ½ 5½ 5 3 /6 3 6⅛ 3/6 8⅜ - 0⅝ 6⅛ 8⅜ ½ 5/6 25 70 300 490 3948-3928 [] 2 5 3 /6 5 9 /6 3 3 /6 6½ ⅞ 9⅜ - 2 5 /6 8⅛ 9⅜ 2 3 /6 39 3 300 490 3948-3928 [] 2½ 6 /6 6 /6 4⅛ 7½ - 4 /6 2⅜ 2½ ¼ 47 63 600 935 6977-6953 [] 4⅞ 5½ 2 9 /6 2.33 8¾ ½ 9⅜ 4¼ 6 5/6 9 50 600 935 6977-6953 [] ½ 5 3 /6 7⅛ 3 3.92 7¼ ½ 0⅝ 6 7 /6 ½ ½ 5/6 7 82 600 935 6977-6953 [] 2 6 3 /6 8⅞ 3 3 /6 3⅜ 2.4 8½ ⅝ 2 5 /6 8½ ½ 2 3 /6 39 25 600 935 6977-6953 [] 2½ 7 /6 0⅞ 4⅛ 4 2.9 9 5 /6 ⅝ 4 /6 2¾ ½ 2½ ¼ 75 74 600 935 6978-6954 [] 4⅞ 5½ 2 9 /6 4⅞ /6 8¾ - 9⅜ 4¼ 6 5/6 9 50 600 935 6978-6954 [] ½ 5 3 /6 7⅛ 3 6⅛ 3/6 7¼ - 0⅝ 6 7 /6 ½ ½ 5/6 7 82 600 935 6978-6954 [] 2 6 3 /6 8⅞ 3 3 /6 6½ ⅞ 8½ - 2 5 /6 8½ ½ 2 3 /6 39 25 600 935 6978-6954 [] 2½ 7 /6 0⅞ 4⅛ 7½ 9 5 /6-4 /6 2¾ ½ 2½ ¼ 75 74 600 935 6977-6977 [2] 4⅞ 5½ 2 9 /6 2.33 - ½ 9⅜ 4¼ 6 5/6 9 50 600 935 6977-6977 [2] ½ 5 3 /6 7⅛ 3 3.92 - ½ 0⅝ 6 7 /6 ½ ½ 5/6 29 82 600 935 6977-6977 [2] 2 6 3 /6 8⅞ 3 3 /6 3⅜ 2.4 - ⅝ 2 5 /6 8½ ½ 2 3 /6 4 25 600 935 6977-6977 [2] 2½ 7 /6 0⅞ 4⅛ 4 2.9 - ⅝ 4 /6 2¾ ½ 2½ ¼ 48 74 600 935 6978-6978 [2] 4⅞ - 2 9 /6 4⅞ /6 - - 9⅜ 4¼ 6 5/6 9 75 600 935 6978-6978 [2] ½ 5 3 /6-3 6⅛ 3/6 - - 0⅝ 6 7 /6 ½ ½ 5/6 29 2 600 935 6978-6978 [2] 2 6 3 /6-3 3 /6 6½ ⅞ - - 2 5 /6 8½ ½ 2 3 /6 4 230 600 935 6978-6978 [2] 2½ 7 /6-4⅛ 7½ - - 4 /6 2¾ ½ 2½ ¼ 48 240 500 2455 6982-6982 [2] 5 5 /6 - ⅝ 5⅞ ⅜ - - 3⅝ 8 5 /6 6 ⅞ 9 80 500 2455 6982-6982 [2] ½ 5⅞ - 2 7 ½ - - 6½ 22⅜ ⅜ /6 25 30 500 2455 6982-6982 [2] 2 7⅜ - 2 /6 8½ ¾ - - 9 /6 27 5 /6 4½ ⅞ ¼ 50 270 500 2455 6982-6982 [2] 2½ 8-2 /6 9⅝ ⅞ - - 9 /6 28 9 /6 4½ ⅞ ¼ 50 300 500 2455 698-698 [2] 4 - ⅝ 2.33 - ½ 3⅝ 7⅝ 6 ⅞ 9 75 500 2455 698-698 [2] ½ 5-2 2⅞.92 - ½ 6½ 2½ ⅜ /6 26 5 500 2455 698-698 [2] 2 6-2 /6 3½ 2.4 - ⅝ 9 /6 26 9 /6 4½ ⅞ ¼ 49 238 500 2455 698-698 [2] 2½ 6-2 /6 4 5 /6 2.9 - ⅝ 9 /6 26 9 /6 4½ ⅞ ¼ 49 238 2500 36 6983-6983 [2] 4 - ⅝ 2¼.33 - ½ 3⅝ 7⅝ 6 ⅞ 9 75 2500 36 6983-6983 [2] ½ 5-2 3 3 /6.92 - ½ 6½ 2½ ⅜ /6 26 5 2500 36 6983-6983 [2] 2 6-2 /6 3⅞ 2.4 - ⅝ 9 /6 26 9 /6 4½ ⅞ ¼ 49 238 2500 36 6983-6983 [2] 2½ 6-2 /6 4½ 2.9 - ⅝ 9 /6 26 9 /6 4½ ⅞ ¼ 49 238 NOTS:. Hardseat-seatless 2. Hardseat-hardseat
YRWY LOW-OFF VLVS STLSS, HRDST ND UNIT TNDM HRDST-STLSS UNIT TNDM VLVS FIGUR 3947-3927 G dia. Lubrication fitting 27 24 25 26 Seatless valve 4 3 6 M dia. D H 7 9 2 28 23 22 Hardseat valve 3 K (closed) L (closed) FIGUR 3948-3928 G dia. Lubrication fitting Seatless valve 4 27 24 25 26 3 6 M dia. R [] D 7 9 2 28 23 22 /6 Hardseat valve 3 K (closed) NOT. See page 3 diameter of raised face (in flange dimensions table) for R dimensions. L (closed) 2
YRWY LOW-OFF VLVS STLSS, HRDST ND UNIT TNDM HRDST-STLSS UNIT TNDM VLVS FIGUR 6978-6954 G 3½ 3½ Lubrication fitting 27 24 25 26 Seatless 5 valve 4 3 6 M dia. R [] D 3 7 9 2 28 23 22 ¼ Hardseat valve K (closed) L (closed) NOT. See page 3 diameter of raised face (in flange dimensions table) for R dimensions. FIGUR 6977-6953 G 3½ Lubrication fitting 3½ 27 24 25 26 Seatless valve 5 4 3 6 M dia. D 7 9 2 28 23 22 3 H Hardseat valve K (closed) L (closed) 3
YRWY LOW-OFF VLVS STLSS, HRDST ND UNIT TNDM HRDST-HRDST UNIT TNDM VLVS FIGUR 6977-6977 27 24 3½ 25 9 7 26 M dia. D 2 28 23 22 H 6 3 K (closed) L (closed) FIGUR 698-698 ND 6983-6983 27 24 25 3½ 9 7 26 28 23 M dia. D 2 22 6 3 H K (closed) L (closed) 4
YRWY LOW-OFF VLVS STLSS, HRDST ND UNIT TNDM HRDST-HRDST UNIT TNDM VLVS FIGUR 6978-6978 27 24 3½ 25 9 7 26 28 23 M dia. R [] D 22 2 3 6 K (closed) L (closed) FIGUR 6982-6982 27 24 3½ 25 9 7 28 23 26 L (closed) 28 23 M dia. 2 22 3 6 R [] D 22 3 C K (closed) L (closed) The C dimension for flanged and socketweld valves is pipe-inlet-to-pipe-outlet offset. NOT. See page 3 diameter of raised face (in flange dimensions table) for R dimensions. 5