Injection Tube Cleaning; Injection Tube Disassembly - pick heaters 6X7 Service Manual

PICK VARIABLE FLOW SERVICE MANUAL
1. Disconnect the steam line union
located between the steam valve and
the heater.
2. Loosen the double-end bushing one-
quarter turn, and remove the steam
line nipple to facilitate removal of
the double-end brushing.
3. Unscrew the double-end bushing
from the heater housing and remove
the injection tube assembly if
required. (Most service procedures
can be performed with the tube in
the bushing.)
IMPORTANT: The injection tube is
machined to close tolerances and is a key
component of your Pick heater. It can be
removed from the double-end bushing an
8-inch pipe wrench. Larger wrenches are
not recommended.
IMPORTANT: The proper location for
placement of the wrench is between the
threads and the roll in the tube SEE
FIGURE 4.
INJECTION TUBE INSPECTION (ALL
MODELS)
Inspect the injection tube. If mineral
deposits are evident, clean the tube as
described in Injection Tube Cleaning.
The piston must move freely in the tube.
Use a clean rod, placed in the threaded end
of the tube. Manually move the piston
through is full travel. Work the piston up
and down several times. It must move to the
spring stopper and return smoothly. If the
piston does not move smoothly, proceed
with disassembly ad further inspection of the
injection tube components.
Note: The injection tube assembly can be
returned to the factory for prompt and
comprehensive servicing. Cleaning,
inspection, and repair or replacement of
parts will be performed as necessary to
return the part to original specifications.
Many customers keep a spare injection tube
on hand to minimize downtime during
maintenance.
INEJCTION TUBE CLEANING (ALL
MODELS)
CAUTION: When handling and
using a cleaning solution, be
sure to follow the
manufacturer's instructions to prevent
personal injury or damage to equipment.
As a minimum, wear goggles and rubber
gloves. The cleaning should be performed
in a location with good ventilation.
It is not necessary to remove the piston for
cleaning if the piston is not stuck. If the
piston moves freely in the tube and no
damage is noted, proceed with cleaning.
Submerge the injection tube assembly in a
container of cleaning solution- (descaling
agent). Refer to OBTAINING THE
PROPER CLEANING SOLUTION
Section, page 11, for recommended cleaning
solutions.
After 30 minutes, flush the injection tube
with water. Inspect the injection tube to
determine whether all the scale has been
removed. BE SURE THE PISTON
MOVES FREELY INSIDE THE TUBE.
If necessary, re-submerge the tube in the
cleaning solution. When all scale is
removed, and the piston moves freely, flush
completely with water. Reinstall the
injection tube assembly, then reassemble the
heater, per the following instructions.
IMPORTANT: Do not leave the injection
tube assembly in the cleaning solution
longer than required. Extended contact
may damage the spring or tube.

INJECTION TUBE DISASSEMBLY

CAUTION: The spring stopper
is under a moderate spring
load. Hand pressure can
restrain the spring force. However, care
should be exercised when removing the
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