Tr o u b l e s h o o t i n g l
6-29
6
Tro
ub
le
sh
oo
tin
g
Poor Material Dr ying
Troubleshooting
Occasionally, processing problems that are suspected of being caused by poor
drying are eventually determined to be the result of other issues in the process
setup. The intent of the information provided here is to assist you in determining if
your drying system is performing properly. However, the only way to know
definitely if your material is properly dried is to perform moisture analysis of
small samples as it leaves the bottom of the hopper, or just as it enters the process.
Conair does not sell moisture-analyzing equipment, but there are many brands of
this equipment available on the market.
You should also be aware that some processing problems may actually be the
result of over-drying material. Most materials will degrade to some extent if they
are exposed to their specified drying temperature for a time significantly longer
than the residence time specified by the supplier. If you want to maintain its dry-
ness, it is recommended that you reduce the process air temperature. If your Conair
dryer is equipped with the Setback feature, you should familiarize yourself with it,
and make use of it. If not, you may want to contact Conair to determine if it can be
added to your dryer.
A majority of customer questions to Conair are related to dew point. It is important
to realize that dew point is one of
four
requirements that need to be satisfied.
There are four requirements, listed in order of importance, necessary to
properly dry hygroscopic plastic resins:
1
Drying temperature
of the air entering the hopper must be at the proper
drying temperature for your material, as specified by your material supplier.
2
Residence time
is the time, determined by your material supplier, that the
material in use must be heated to achieve proper drying temperature.
3
Air flow
during the process drying circuit must be adequate to carry and
distribute the heat throughout the entire bed of material inside the hopper.
4
Dew point
of the process air must be low so it can efficiently collect the
moisture as it is released from the heated material and carry it to the dryer to
be removed in the desiccant.
NOTE:
Concerns with drying
temperature may require
review of HTC or GasTrac
controls.
✐
Содержание HTC 120
Страница 10: ...viii l Table of Contents ...
Страница 30: ...2 14 l Description ...
Страница 35: ...Installation General Installation General l 3 5 3 I n s t a l l a t i o n ...
Страница 65: ...Installation Hard Piping Kits Installation Piping Hoses l 3 35 3 I n s t a l l a t i o n ...
Страница 80: ...3 50 l Installation Piping Hoses ...
Страница 81: ...3 I n s t a l l a t i o n Installation Main Power Connections Installation Main Power Connections l 3 51 ...
Страница 88: ...3 58 l Installation Piping Hoses ...
Страница 89: ...3 I n s t a l l a t i o n Installation Main Power Connections l 3 59 Installation Conveying Lines ...
Страница 92: ...3 62 l Installation Conveying Lines ...
Страница 93: ...Installation Water Lines 3 I n s t a l l a t i o n Installation Water Lines l 3 63 ...
Страница 115: ...Installation Compressed Air Lines 3 I n s t a l l a t i o n Installation Compressed Air Lines l 3 85 ...
Страница 124: ...3 94 l Installation Gas Piping and Exhaust Flue ...
Страница 125: ...Installation Testing 3 I n s t a l l a t i o n Installation Testing l 3 95 ...
Страница 149: ...4 O p e r a t i o n Operation l 4 7 Control Function Flow Charts continued Operation Flow Chart 1 1A 2 3 4 continued 5 ...
Страница 152: ...Control Function Flow Charts continued Setup Flow Chart 1 1B 19 38 20 34 37 4 10 l Operation continued ...
Страница 250: ...4 108 l Operation ...
Страница 286: ...5 36 l Maintenance ...