Desiccant; Mufflers - Sigma HRD Serie Manual De Instrucciones

Consult your local distributor for piping details if re-
quired.
Dryer bypass piping may be installed to allow uninter-
rupted airflow during servicing. If the downstream ap-
plication cannot tolerate unprocessed air for short
periods, install a second dryer in the bypass line.
CAUTION
Do not hydrostatically test the piping with the
dryer in the system. The desiccant will be
damaged if saturated with water.

Desiccant

HRD and HRD-EM Series dryers use activated alu-
mina as the desiccant in the dryer vessels.
Models 56 through 600 scfm are shipped with acti-
vated alumina in the dryer vessels. Activated alumina
is shipped loose with all other standard models.
All desiccant shipped loose must be added to the
dryer vessels before the dryer is put into service.
Refer to Table 2 for quantity per vessel.
Table 2
DESICCANT REQUIREMENTS
Dryer Model No
HRD56 / HRD56EM
HRD100 / HRD100EM
HRD160 / HRD160EM
HRD200 / HRD200EM
HRD275 / HRD275EM
HRD350 / HRD350EM
HRD475 / HRD475EM
HRD600 / HRD600EM
HRD800 / HRD800EM
HRD1000 / HRD1000EM
HRD1200 / HRD1200EM
HRD1450 / HRD1450EM
HRD1710 / HRD1710EM
HRD2010 / HRD2010EM
HRD2250 / HRD2250EM
HRD2600 / HRD2600EM
HRD3250 / HRD3250EM
HRD and HRD-EM Series (Bulletin 378)
Activated Alumina
(lbs per vessel)
31
60
95
120
165
210
285
366
475
600
725
880
1,025
1,200
1,366
1,567
1,975
To add desiccant:
WARNING
The following procedure provides instructions
for adding the initial desiccant to the vessels. If
replacing desiccant, refer to the instructions
on page 1-13.
1. Verify pressure gauges of both vessels indicate 0
psig. If not, depressurize the vessels according to
the shutdown instructions on page 1-12.
2. Remove the pipe plug from the desiccant fill port
at the top of each vessel. Refer to the dryer label
for the schematic depicting the fill port location.
CAUTION
Pouring desiccant creates a fine dust; safety
goggles, gloves and dust mask should be
worn by personnel installing desiccant. Refer
to the Material Safety Data Sheet (MSDS) on
page 1-23 for more complete information.
Do not tamp the desiccant in vessels. Tamping
damages desiccant and causes dusting.
3. Carefully pour activated alumina into the vessels
through the fill port.
4. Tap the vessels with a rubber mallet to ensure uni-
form distribution of the desiccant.
5. Replace the plugs in the fill port connections.

Mufflers

Purge exhaust mufflers are supplied with every dryer.
If they are not factory installed, they must be screwed
into the purge exhaust connection on the lower mani-
fold piping before the dryer is operated. Desiccant
dusting may cause a restriction in the purge exhaust
muffler shortly after start-up. Depending on the dryer
model, the muffler cores may be in the control enclo-
sure or strapped to a vessel leg. For additional infor-
mation see Desiccant Dusting in the Maintenance
section, page 1-11.
WARNING
Operating dryer without mufflers will cause
noise levels exceeding OSHA standards.
Remove mufflers only for servicing and
maintenance and only after internal pressure
of dryer has been completely vented to
atmosphere.
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