DMD4 Optical Type Portable Desiccant Dryer/Loader
 
Maintenance

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Maintenance Item Frequency Work Details Notes
(1)
Temperature Controller
Daily Check to see if the regenerate/drying temperature is being run by the temperature set on the controller.

1. Press the Controller SV switch, allow the "SV" to appear and check set temperature of drying temperature.
2. Press the SV switch to display the drying temperature and check actual temperature. Compare with setting temperature.
3. If difference in temperature is +/- 2~3C, function is normal.
  Regenerate PV temperature may not reach standard SV temperature on periods when temperature is low and cool. (standard SV is 220C)
  If pressing the RESET and SV switch at the same time when the drying temperature is displayed on the controller PV and the SV display, the regenerate temperature will appear only during time the switches are held.
(2)
Convey Blower
Drying Blower
Regenerate Blower
Inspect to see if there are any noises (esp. metallic noises) or vibrations.
  Do not operate when unit is making noises or vibrating.
* If any abnormality is found, stop unit immediately and look into causes.
(3)
Convey Air Main Unit Dust Box (option)
After fully closing the butterfly valve of the lower half of the cyclone, remove the dust box and remove the particles stuck in the box.
  When removing the particles, fully close the butterfly valve and remove the dust box.
* After completing work, securely place dust box back in place and fully open the butterfly valve.
* If the packing is deteriorating badly, or is deforming, discoloring or hardening, replace with new packing.
(4)
Connecting Hose
Check each hose connection to see if hose vacuuming is not too weak or strong. Tighten hose band if necessary.
* If the hose is wearing badly, is hardened or damaged badly, replace with new hose.
(5)
Cooling Water
Weekly Check to see if cooling water is running from the inlet/outlets of the cooling water section.
  If water is not running, unit will not be controlled at the temperature specified or may lead to damage to the unit.
(6)
Regenerate Filter
Cleaning
(Regenerate Filter)
Remove the filter under instructions below: Then see if filter is not clogging.

1. Squeeze filter holder up and down and remove.
2. Remove regenerate filter.
  When blowing dry air to clean out, wear a mask for particles may fly in the air during the cleaning.
  If filter is clogged, operating temperatures may vary badly, cause air rate variations and cause fire hazards.
  If clogged, blow clean dry air to remove particles.
  Enviroment of dryer may effect dirtiness of filters. Thorough inspection and cleaning is recommended.
  After inspection, return filters back to original position securely.
(7)
Drying/Conveying Filter Cleaning
(Drying Filter, Conveying Filter) Remove the filter case lid of the dehumidifying dryer unit and see if filter inside is clogged or not.
(8)
Strainer Cleaning
Remove screw flange of the strainer and remove any of the internal residue. After inspection, put screw flange back to original position and make sure water leakage does not happen.
  There may be extra release pressure in cooling water pipes. Make sure there is no release pressure before starting work.
  If cooling water does not run in strainer because of residue or particles, drying dew point temperature will not drop and cause drying defects.
(9)
Solenoid Valve/Contactor
Check both solenoid valve and contactors to see if there is no weld damage or wear.
  Before inspecting, please turn the breakers at the front is turned off.
  If there is weld damage or wear on either units, replace with new parts.
(10)
Terminals
Monthly Check to see if wirings are loose in control panel and in the unit. Tighten if loose wiring is found.
  Before inspecting, please turn the breakers at the front is turned off.
(11)
Nylon Tube
(air tube)
Inspect to see if nylon tube is deteriorating or damaged.
* If the nylon tube is deteriorating badly, hardened or damaged, replace with new nylon tube.
(12)
Primary Convey
Collector/Forming
Unit Collector
Monthly/Every Material Change Open the top lid of the collector and see if filter is clogged or not. If clogged, clean by blowing clean dry air to remove particles.
  Use extra caution to keep filter from deforming. May cause defects from air leaks.
  Wear a mask when cleaning. Particles blown by the dry air will scatter in air.
  If filter is clogged, this may lead to convey blower overload and decline in convey function. Extra caution needed when handling.
* If blowing dry air does not remove all of the particles, use a pointed needle to remove.
* If the packing is deteriorating badly, deformed, discolored or hardened badly, replace with new packing.
(13)
Bolts/Nuts
Every 3 Months Check every bolt and nut for looseness.
Tighten if looseness is found.
 
(14)
Rotor Drive Belt/
Tension Board Spring
Every 6 Months Inspect to see if rotor is cracked, damaged or loose.
* If abnormality is found, replace belt. Contact local Matsui service.
(15)
Filter
- Inspection
Every Material Change (HEPA Filter)
On HEPA Filter, if manometer exceeds 500Pa, replace filter.
<Instructions>
1. Remove cover board at the back of the controller. There should be a HEPA filter.
2. Loosen the wing nut and wing bolt to remove the HEPA filter.
3. Install new HEPA filter. Install to make packing of filter faces downstream (drying hopper side)
4. Tighten wing bolt (4 areas) by hand to make HEPA filter packing tightly adhere to filter case.
 
(16)
Hopper Dryer
- Cleaning
Clean only during material changes or any other special circumstances. See below for instructions.

1. Removal of material.
Remove material from outlet on bottom of hopper. Below the outlet, disassemble conveying pipes, use the manual knob of the damper drive solenoid valve to open damper. Solenoid valve is on the outer board of the back of the controller.
2. Open the hopper dryer door and remove the diffuser cone. Clean with clean dry air.
3. Remove pellets and dust in hopper and assemble back to normal.
4. After completion of work, run dryer with hopper clean inside. (purge hopper with clean air)
 

* For safety purposes, please turn off power of unit when performing inspections.
* When working on drying hopper section, due to accumulated high temperatures, turn the drying switch off and allow the hopper area to cool off. Start inspections or cleaning after making sure the hopper section has cooled off.
* Stop air flow going to measuring units. Also, release any air remaining inside sections after the primary supply valve.