Yokogawa Single Channel Oxygen Analyzer System ZR22/ZR402 - Manual (Page 175)

IM 11M13A01-02E 11-4
3. Part assembly procedure
(1) First, install the contact. Being careful not to cause irregularities in the pitch of the
coil spirals (i.e., not to bend the coil out of shape), place it in the ringed groove
properly so that it forms a solid contact.
Groove in which the contact
(E7042BS) is placed
F11.2E.EPS
Figure 11.2 Installing the Contact
(2) Next, make sure that the O-ring groove on the flange surface of the sensor is clean.
Install the metal O-ring in that O-ring groove, and then insert the sensor in the probe
while turning it clockwise. After inserting it until the metal O-ring comes in contact
with the probe’s O-ring contact surface, properly align the U-shaped-pipe insertion
holes with the bolt openings.
(3) Attach the U-shaped pipe to its support with filter, then fully insert the U-shaped
pipe and its support into the probe.
(4) Coat the threads of the four bolts with antiseize grease and then screw them in along
with the washers. First, tighten the four bolts uniformly by hand, and then use a
torque wrench to tighten all areas of the metal O-ring uniformly, that is, to make sure
the sensor flange is perfectly horizontal to the O-ring’s working face in the probe.
This is done by tightening first one bolt and then its opposing bolt each 1/8 turn, and
then one of the other bolts followed by its opposing bolt, each also 1/8 turn. This
continues in rotating fashion until they are all fully tightened with the torque wrench
preset to approximately 5.9 N • m. If they are not uniformly tightened, the sensor or
heater may be damaged.
Replacement of the sensor assembly is now complete. Attach and fix the Flame
Arrester Assembly. Install the detector and restart operation. Calibrate the instrument
before making a measurement.