Mechanical Packings Installation Guide - Rottech
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    Mechanical Packings Installation Guide




    Step No.1
    Remove all old packing, using care not to damage stem or bore.
    If the stuffing box has a lantern ring not in use ( no leak off), remove it and all packing below it. The latern ring will not be re-installed.
    The stuffing box must be clean. Packing material fragments can prevent new packing rings from fully seating against stuffing box wall.
    Also, thoroughly clean valve stern, packing gland, gland followers, studs,nuts.
    Inspect stem, gland and bore from worn,scored,grooved or galled conditions that no longer meet. Manufacturer’s specifications.

    It may be necessary to rework or replace these valve components



    Step No.2
    Determining Ring Size
    Follow this procedure to select the correct packing cross-section:
    a) Measure bore (A)
    b) Measure stern (B)
    c) Subtract stern size from bore size (A-B)
    d) Divide that difference by 2 to get correct packing ring size.




    Step No.3
    Determining Number of Ring
    Follow this procedure to determine the conect number of rings to be used.
    a) Measure depth of box
    b) Divide the cross-section ( from Step No.2 ) into depth measurement. This is the number of rings needs ( Depth divided by ring size equals rings required )






    Step No.4
    Intalling Packing Rings
    Rings should be installed one at a time making sure when using more than 2 rings, stagger joints 90°apart. When using only 2 rings. Stagger joint 180°apart. A split bushing should be used to firmly tamp each ring into the stuuffing box.
    Important: Do not use pointed or sharp tools-scewdriver,chisel,pen point,etc.
    If a lantern ring is used, and the valve has extemal leak off piping, make certain ring is aligned ith leak off port




    Step No5
    Positioning Gland Follower
    A space of 1/8” to 3/16” should remain for gland follower when stuffing box is filled. This assures optimal axial loading on packing.






    Installation for Pump Only
    If a lantern ring is provided, make sure the lantern ring is installed under the pipe tap hole.
    After the last ring is installed, bring the follower down on the packing and finger-tighten the gland nuts. Do not jam the packing by excessive gland loading. Start pump, and tigten the bolts until leakage is decreased to tolerable minimum. Make sure gland bolts are tightened evenly. Stopping leakage entirely at this point will cause the packing to burn up.
    Allow packing to leak freely upon start-up after repack.gradually reducing leakage during the first hour of operation will result in a better seal over a longer period of time. Tighten the gland nuts one flat at a time until the desired leakage is obtained. And the pump is running cool.