To position the Teflon mounted insert, lubricate the inside of the
mechanical seal gland. Carefully slide the Teflon mounting ring into
position in the gland and then slide the insert into place. The slot in
the stationary insert must index with the drive pin.
Put the mechanical seal gland and insert on the shaft and slide it
back against the flinger. Be careful not to damage the insert or its
mounting. Put the gland gasket (324) on the shaft. Slide the seal
rotary unit assembly carefully onto the shaft sleeve being particularly
careful not to damage the seal shaft packing (345). Be sure that the
shaft sleeve hook is firmly against the shoulder on the shaft. Set the
rotary unit carefully to the setting mark you have made on the shaft
sleeve and lock it tightly in place with the set crews. Recheck the set-
ting. Slide the pump casing back cover carefully into place and
guide the seal gland insert and gaskets together with the gland care-
fully into position. Reassemble the pump. Now tighten the gland stud
nuts carefully and evenly to avoid cocking the gland, making sure
that the gland insert and gaskets are in place.
Before starting the pump, bleed the air from the seal chamber. The
seal chamber must be full of liquid or the seal faces may be dam-
aged by lack of lubrication when the pump is started.
Occasionally a seal may leak very slightly when the pump is first
started. It the leakage continues more than a few moments the pump
should be shut down and the seal removed to discover the cause.
Note 1—Pumps using a single inside balanced seal except Type
609 (metal bellows) are furnished with a short shaft sleeve. The
mark is made on the shaft because the sleeve does not extend to
this point. The second mark (setting mark) is made on the shaft
sleeve and measured from the mark on the shaft.
INSTALLATION OF SINGLE OUTSIDE UNBALANCED SEALS
If the seal rotary unit is scribed with a setting mark, the shaft marking
procedure outlined below may be omitted. The setting mark can be
found on the outer shell of the rotary unit running circumferentially
between the four round holes in the shell. Visible through each hole
is the edge of the metal disc against which the seal springs bear. To
set the seal with the proper spring pressure, first assemble the pump
as noted below with the seal rotary unit slid back against the shaft
splash collar and left loose until the entire bearing housing-impeller
assembly is bolted in place in the pump casing. Then slide the seal
rotary unit into place against the stationary insert and compress the
springs until the metal disc visible through the holes is aligned with
the setting mark scribed on the shell. Tighten the set screws and
check through each hole to determine that the seal rotary unit is cor-
rectly compressed and not cocked.
If the seal rotary unit is not marked with a setting line, a setting mark
must be made on the shaft sleeve. To make the seal installation, with
the pump partially assembled as noted above, scribe a mark on the
shaft sleeve (10) exactly in line with the face of the pump seal cham-
ber. The impeller (3), and casing back cover (22) are now removed
from the pump. If the mark causes roughness on the shaft sleeve
remove the burr carefully with crocus cloth. Any roughness on the
shaft sleeve may damage the mechanical seal shaft packing when
the seal is assembled.
Referring to the mechanical seal drawing, determine the proper
“D” dimension for the seal and pump type. Measure carefully from
the mark which you have made on the shaft sleeve and make a
new mark on the shaft sleeve, towards the bearing housing, exactly
to this dimension. Remove the burr if necessary. This mark is the
seal setting mark.
Put the mechanical seal rotary unit on the shaft and slide it back
against the splash collar. Assemble the seal insert gasket (326), the
mechanical seal insert (315), and seal insert gasket (325) to the face
of the seal chamber and, placing the gland (300) in position, pull
down the gland stud nuts tightly and evenly. Make sure that the
lapped face of the seal insert is towards the rotary unit. Reassemble
the pump. Now carefully slide the rotary unit against the seal insert,
compress the rotary unit and set it to the mark on the shaft sleeve
and lock the rotary unit tightly in place with the set screws. Be careful
not to cock the rotary unit.
Before starting the pump, bleed the air from the seal chamber. The
seal chamber must be full of liquid or the seal faces may be dam-
aged by lack of lubrication when the pump is started.
Occasionally a seal may leak very slightly when the pump is first
started. If the leakage continues more than a few moments the pump
should be shut down and the seal removed to discover the cause.
INSTALLATION OF DOUBLE INSIDE UNBALANCED SEALS
To make the seal installation, with the pump partially assembled as
noted above, scribe a mark on the shaft sleeve (10) exactly in line
with the face of the pump seal chamber. The impeller (3) and casing
back cover (22) are now removed from the pump. If this marking or
subsequent marking causes roughness on the shaft sleeve remove the
burr carefully with crocus cloth. Any roughness on the shaft sleeve
may damage the mechanical seal shaft packing when the seal is
assembled.
Referring to the mechanical seal drawing, determine the two “D”
dimensions for the two rotary units. Be sure to determine those for the
particular pump type. Measure carefully from the mark which you
have made on the shaft sleeve and make two new marks on the
shaft sleeve, towards the pump end, exactly to these dimensions.
Double seal stationary inserts are two types depending on the ser-
vice conditions of the pump. The insert may be of rectangular cross
section grooved for an o-ring or the insert may be of L-shaped cross
section used with a Teflon mounting ring.
To position the o-ring mounted insert, lubricate the inside of the seal
chamber and the inside of the mechanical seal gland. Place the
o-rings in the grooves and carefully slide the inserts into position in
the seal chamber and seal gland. Be most careful not to damage the
o-ring.
To position the Teflon mounted insert, lubricate the inside of the seal
chamber and the inside of the seal gland. Carefully slide the Teflon
mounting rings into position and then slide the stationary inserts into
place. The slots in the stationary inserts must index with the drive pins.
Put the mechanical seal gland, with insert installed, on the pump
shaft sleeve and slide it back against the splash collar. Put the seal
gland gasket on the sleeve and slide it back against the gland. Slide
one seal rotary unit on the sleeve with the carbon face towards the
bearing housing. Be careful not to damage the seal shaft packing.
Be sure that the shaft sleeve hook is firmly against the shoulder on the
shaft. Set the rotary unit carefully to its setting mark on the shaft
sleeve and lock it tightly in place with the set screws. Slide the sec-
ond rotary unit onto the shaft sleeve with the carbon face away from
the bearing housing. Set it carefully to its setting mark and lock it
tightly in place. Recheck both rotary settings and correct if necessary.
Slide the pump casing back cover very carefully in place over the
seals. Slide the gland gasket and seal gland into place and carefully
and evenly tighten the gland stud nuts. Do not cock the gland. The
pump may now be reassembled.
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