Davis Standard - Starting the year right

I bet we can all agree we’re thankful for a new year! And now that we’re here in 2021, let’s kick the year off right! What better way than to start with maintenance. In this blog, we provide a checklist to ensure your extruder is primed for peak performance. Here are the 10 extruder components we suggest checking as part of a healthy maintenance plan. Each one of these items is recommended for quarterly maintenance unless otherwise noted.

Control Panel

  • Clean and inspect inside of the control panel. Look for burned wiring and signs of component overheating.
  • Make sure all terminal connections are tight.
  • Check that receptacles are grounded.
  • Test and monitor operating conditions. Check amp draw of three-phase motor input.
  • Check and calibrate all temperature and pressure controllers.
  • Check all ground connections and verify continuity (yearly).
  • Check and verify drive potentiometer speed, as equipped (yearly).

Feedscrew and Barrel

  • Clean and inspect pressure gauge transducer.
  • Measure and record feedscrew flight and barrel diameters (yearly).
  • Conduct Liquid Penetrate Non-Destructive Test (NDT) for cracks on feedscrew and barrel (yearly).
  • Clean and inspect feedscrew and barrel (as needed).

Bolted Connections

  • Check all bolt and mounting hardware throughout the entire system for tightness and damage.
  • Reference component torque requirements in your maintenance manual.

Electrical Connections

  • Inspect all conduits for wiring and damage.
  • Inspect electrical leads for cuts, fraying abrasions or other damage.

Feed Section and Hopper

  • Inspect feed section and hopper for excess wear and damage.
  • Clean and inspect feed section cooling passage.
  • Check feedscrew bushing for excess play and wear (as needed).

    Barrel Heaters

  • Measure and record heater amperage and resistance.
  • Clean and inspect barrel heater fins.
  • Check all thermocouple and heater terminal connections.
  • Measure and record blower fan motor temperatures. 

Barrel Blowers

  • Clean and inspect blower intake and exhaust for proper flow and ventilation.
  • Measure and record fan motor temperature.
  • Lubricate blower motor (as needed).

Water Cooling System and Rotary Unions

  • Inspect pump seals for leaks.
  • Test and calibrate pressure and temperature regulators (yearly).
  • Check water flow from plant water supply lines (yearly).
  • Clean and inspect heat exchanger (as needed).
  • Check the zinc anode plug for deterioration and corrosion (as needed).

Electric Motors

  • Inspect all electrical connections and wiring for tightness and damage.
  • Check belts for excess wear and proper tension (deflection).
  • Clean and inspect internal component conditions of motor (yearly).
  • Test and record the condition of all operating components (as needed).
  • Lubricate motor bearings (according to manufacturer instructions).

Gear Reducer

  • Check oil cleanliness on lube system and oil filter.
  • Clean gearcase of sediment, sludge and metal particles.
  • Visually inspect gear sets for damage and wear through site glass.
  • Check bearing noise and vibration.
  • Check thrust shaft run-out and bearing play.
  • Check drive coupling for proper alignment (yearly).
  • Lubricate drive coupling (as needed).
  • Change oil in gear reducer (as needed or every 4,000 hrs.).
  • Clean and inspect heat exchanger (as needed).