Hancock 1500, 2500 and 4500 Pound Forged ... - Industrial Controls

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gland stuffing box pitting has occured. The packinggland nuts should be suffciently loosened to allowcounterclockwise rotation of the stem to backseatthe valve. Then the valve should be tagged forinspection to determine if the stem should bereplaced during the next system outage.If the gland is adjusted to it’s full travel, but theleakage has not stopped and stem binding has notoccured, addition of packing is indicated.Available valve packings are! ATTENTIONshown in Figures 3 and 3A, andapplicable part numbers are shown inTables 4 and 4A. Do not attempt tobackseat and add packing to looseDo not backseat and add packing to aloose backseat valve under pressure,backseat valves while they areas this will result in severe personalinjury or deathpressurized.TABLE 4—Packing CartridgesValve SizePart Numbers1500 Class 2500 class 4500 Class1/4 7220802 7220802 72208123/8 7220802 7220802 72208121/2 7220802 7220802 7220812Fixed 3/4 7220801 7220801 7220813Backseat 1 7220801 7220801 72208131-1/4 7220804 7220804 72208141-1/2 7220804 7220804 72208152 7220804 7220804 72208161/4 7220807 7220807 72208093/8 7220807 7220807 72208091/2 7220807 7220807 7220809Loose 3/4 7220805 7220824 7220810Backseat 1 7220805 7220824 72208101-1/4 7220806 7220806 72208111-1/2 7220806 7220806 72208112 7220806 7220806 7220811TABLE 4A—Packing SetWith Individual Split RingsFIGURE 3Cartridge6FIGURE 3APacking SetBefore attempting to add packing to a loose backseatvalve, verify that there is no pressure in theline. After determining that the line is not pressurized,loosen and remove the packing gland studnuts on the packing gland flange. Move the packinggland flange along the stem until it contacts thethread bushing portion of the yoke. Next, removethe two halves of packing gland and the upper bullring. Install the required numbers of split, compressedgraphite rings around the stem and intothe gland stuffing box. (Always add a new outerbull ring when adding packing.) Place the twohalves of the packing gland on the stem andagainst the packing. Slide the packing gland flangeover the packing gland. Then slide the two packinggland studs through the two holes in the packinggland flange. Install the packing gland nuts onto thepacking gland studs. Tighten by rotating the nutsclockwise in 1/2 turn increments, alternatingbetween nuts. A final adjustment may be necessaryafter the valve has been pressurized.Note: Adding packing to fixed backseat valves,with no pressure in the line, is done in thesame way as for loose backseated valves.Valve SizePart Numbers1500 Class 2500 class 4500 Class1/4 7221102 7221102 72211123/8 7221102 7221102 72211121/2 7221102 7221102 7221112Fixed 3/4 7221101 7221101 7221113Backseat 1 7221101 7221101 72211131-1/4 7221104 7221104 72211141-1/2 7221104 7221104 72211142 7221104 7221104 72211141/4 7221107 7221107 72211093/8 7221107 7221107 72211091/2 7221107 7221107 7221109Loose 3/4 7221105 7221124 7221110Backseat 1 7221105 7221124 72211101-1/4 7221106 7221106 72211111-1/2 7221106 7221106 72211112 7221106 7221106 7221111J. Adding Packing orRepacking Under Pressure1. General InformationHancock/Yarway Tee Pattern Globe Valveswith fixed backseats, incorporate design featureswhich make it possible to add packing orchange packing while the valves are underpressure. Nevertheless, Hancock/Yarwaydoes not recognize the adding or changingof packing to fixed backseat valves under
pressure as a safe practice and ! CAUTIONtherefore discourages sech repackingwhen not indicated byoperational necessity. (Again,see “Safety Precautions”Do not repack a fixed backseat valveSection 2.)under pressure unless it is absolutelynecessary to avoid possible personalinjury.2. Specific StepsIf operational considerations dictatethat adding or changing! DANGERpacking in a fixed backseat valveis absolutely necessary, adherenceto the following steps is recommendedto reduce the possibil-If a valve nameplate cannot be read oris missing, do not add or change packingunder pressure, as this will result insevere personal injury or deathity of personal injury.a. Check the valve nameplate to be sure it ismarked “fixed backseat”. If it does not sayfixed backseat, or the nameplate cannotread or is missing, DO NOT attempt to addpacking if the valve is under pressure.b. Once it has been determined that the valveis of the fixed backseat design, rotate thetee handle counterclockwise until the discnut contacts the yoke bushing. Firmly backseatthe valve by applying torques as listedin Table 2, Section 4 of this manual.c. Remove the valve tee handle to preventaccidentally rotating the stem.d. Loosen the packing gland stud nuts byrotating them one full turn counterclockwise.e. Wait 2 to 3 minutes, then visually check thevalve packing for leakage.f. If no leakage is detected, slowly loosen thestud nuts until the gland flange is no longertight against the packing gland. Do notremove the nuts at this point. Again, wait 2to 3 minutes and check to be sure that thegland flange has not been forced tightagainst the gland by pressure.g. Once assured the backseat is not leaking,remove the two packing gland stud nutsand packing gland nut.k. Spread open the cut in the individual compressedgrafoil ring just enough to slip itonto the stem. Slide the individual rings intothe gland stuffing box, being careful toplace the split on successive rings 90°apart. This will ensure that no possible leakpath exists when re-packing is complete.l. The last ring to be installed must be a braidedgraphite filament “bull ring”.m. Reassembly the packing gland, gland studnuts and tee handle as described in the Reassemblyinstructions (Section 4.m) of thismanual.n. Tighten the packing as described in Section4.l of this manual.K. Disassembly1. Loose Backseat Valves(For parts nomenclature, refer to Figure 1Section 4 of this manual.)Remove the two packing stud nuts which arelocated above the packing gland flange by acounterclockwise rotation. Remove the twopacking gland studs and two remaining studnuts. Move the packing gland flange along thestem toward the tee handle, then remove thetwo halves of the packing gland.Rotate the tee handle counterclockwise untilthe disc nut contacts the backseat. Removethe tee handle locknut by a counterclockwiserotation. Observe that the thread bushing hasbeen stake locked at the factory to prevent it’srotation during valve operation, (see Figure 4).Because of this factory stake locking, theraised boss must now be removed before thethread bushing can be removed from the yoke.The stake lock may be removed by peering, orby a hand held grinder or a file. Remove thethread bushig by rotating it counterclockwise.Note: The stem should br prevented fromrotation while the bushing is being rotated.Notes: If packing is only to be added to thevalve, it may be done at this point.If the packing is to be totally changed in thevalve, adhere to the requirements of stepsh-n, below.h. Remove the old packing by using a corkscrew or wire hook.i. A new split ring packing set can now beinstalled in the valve.j. Place a bull ring around the stem at thearea between the yoke arms, then slide thering into the gland stuffing box.FIGURE 4—Stake Lock7
Page 3: Product Safety Sign and Label Syste
Page 6 and 7: TABLE 1ValveSizeA B C D{ -.000 }+.0
Page 10 and 11: After each 10 complete rotations of
Page 12 and 13: Note: The following procedures for
Page 15 and 16: M. Reassembly1. General Information
Page 17 and 18: Having parts immediately available

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