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

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After each 10 complete rotations of the threadbushing, the stem should be rotated counterclockwiseuntil it contacts the backseat. Thisaction will ensure that the disc does notengage the seat and bind the thread bushing.After the thread bushing has been disengagedfrom the yoke, continue the counterclockwiserotation until the bushing disengages from theAcme thread on the stem.The packing and stem/disc assenbly can nowbe removed in one operation. The packinggland can be used to accomplish this by placingthe two halves of the packing gland in thethread bushing opening of the yoke. (SeeFigure 5.)Screw the thread bushing onto the stem byrotating it clockwise until it contacts the packinggland. Install the tee handle and rotatecounterclockwise until all the packing is drawnout of the gland stuffing box. The entireassembly can now be removed. Now, removethe old packing from the stem.FIGURE 6—Disc-To-DiscNut Tack WeldFIGURE 6A—Disc-To-DiscNut Stake Locked8FIGURE 5The disc and disc nut are now locked togetherby either a tack weld or by staking. (See Figure6 and 6A). If they are locked by welding, theweld must be ground off before disassembly.After the weld has been removed, place thedisc in a vice between two soft pieces ofmetal, such as brass.The soft metal will prevent damage to the discO.D. Next, remove the disc nut by rotating itcounterclockwise. The stem and the disc padcan now be removed.2. Fixed Backseat Valves(For parts nomenclature, refer to Figure 2Section 4 of this manual.)Remove the two packing stud nuts locatedabove the packing gland flange, by a counterclockwiserotation. Remove the two packinggland studs and the two remaining stud nuts.Move the packing gland flange along the stemtoward the tee handle. Then remove the twohalves 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 the valve operation (again, refer
to Figure 4 (Section 4), thus the raised bossresulting from stake locking must be removedbefore the thread bushing can be removedfrom the yoke. The stake lock may be removedby peening, or by a hand held grinder or file.Remove the thread bushing by rotating it counterclockwise.Note: The stem should br prevented fromrotating while the bushing is being rotated.After each 10 complete rotations of the threadbushing, the stem should be rotated counterclockwiseuntil it contacts the backseat. Thisaction will ensure that the disc does notengage the seat and bind the thread bushing.After the thread bushing has been disengagedfrom the yoke, continue the counterclockwiserotation until the bushing disengages from theAcme thread on the stem.The packing of the fixed backseat globe valvemuct now be removed by using the packingremoval tool, shown in Figure 7, and for whichapplicable valve size and part number informationis provided in Table 5.Touse the packing removal tool, place the toolover the stem, through the thread bushingopening of the yoke and into the gland stuffigbox. Next, place a rod through the hole in theremoval tool. Using the rod, rotate the toolclockwise while exerting force on the tooltoward the packing. Remove the tool andclean the packing from the flute after each 3 to5 complete rotations. Repeat the operationuntil all the packing is removed. The packingstop ring can now be removed, and this canbe done by screwing a piece of No. 8-32threaded rod into one of the two tapped holesin the ring, or by using a wire hook in one ofthe two tapped holes.The yoke bushing nut is removed by using thewrench shown in Figure 8, and for whichapplicable valve size and part number informationis provided in Table 6.FIGURE 8—Yoke Bushing Nut WrenchTABLE 6—Wrench SelectionFIGURE 7—Packing Removal ToolTABLE 5—Packing Removal Tools P/NSVavle SizeP/N1/4, 3/8, & 1/2 71019093/4 & 1 71019011-1/4, 1-1/2 & 2 7101910Vavle SizeP/N1/4, 3/8, & 1/2 71019093/4 & 1 71019011-1/4, 1-1/2 & 2 7101910Insert the tool through the thread bushingopening, and into the gland stuffing box, withthe lug end first. Rotate the wrench until thelugs engage the slots in the yoke bushing nut,then screw the wrench nut into the threadbushing of the yoke until it hits the shoulder onthe wrench. (See Figure 9)9
Page 3: Product Safety Sign and Label Syste
Page 6 and 7: TABLE 1ValveSizeA B C D{ -.000 }+.0
Page 8 and 9: gland stuffing box pitting has occu
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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