Designing a Combustion Air/Gas Pre‐Mix System For Red‐Ray Infrared Process Burners

  1. Determine load requirements based on application (BTU/hr)
  2. Choose burner type based on process / application / requirements
  3. Determine number of burners required and configuration (number of burners per row based on oven and product constraints)
  4. Determine Ignition / Monitor Methods
    1. RP‐I / RP‐M for burners less than 4 ft
    2. IPQ‐1 / MPQ‐1 for burners greater than 4 ft
    3. UV Scanners
    4. IW (ignition wire) and MW (monitor wire) length (~25‐50 ft per burner)
  5. Mixer selection (based on 1 mixer per 1 row of burners)
    1. Determine mixture pressure (based on burner type) and gas volume per row (1,000 BTU/hr = 1 CFH)
    2. Use the Pyronics Flomixer Data Sheet to select mixer (Manufactured Gas – 1000 BTU – 0.6 Sp Gr)
    3. Round up to higher capacity air insert size (1/32″)
    4. Pyronics Flomixer – highly recommend which includes
      1. Manual butterfly valve
      2. Air Sleeve and insert combined to create suction
      3. Gas Adjuster valve for air/gas ratio adjustment
      4. Zero gas regulator (BZR)
      5. Gas shut‐off cock
      6. Flanged outlet
  6. Blower Selection (16 oz static pressure – LC Series 4121)
    1. Determine SCFHair required
      1. Total system load (BTU/hr) ÷ 1000 = SCFHgas
      2. CFHgas x 11 (11 to 1 air gas ratio) = SCFHair
    2. Use SCFHair to determine 16oz blower model from the Pyronics Blower 4121 Data Sheet.
      1. Specify blower model #, discharge position, motor HP, TEFC (total enclosed fan cover), voltage
      2. Select flexible sleeve with clamps (same size as blower outlet)
    3. Specify Air Filter
      1. Non‐washable Cylindrical Element
      2. Round Replaceable Element
  7. Select Combustion Air Pressure Switch – (10″- 30″ w.c. range)
  8. Select All‐In‐One Gas Train Assembly
    1. Based on total CFHgas (to include all burners and pilots)
    2. Assembly to include
      1. Main shut‐off ball valve
      2. Main pressure regulator
      3. Low and high gas pressure switches
      4. Visual and electronic position indication switches
      5. Double blocking valve
      6. Threaded body flange
  9. Select Main Gas Shut‐Off Ball Valve (size based on plant gas line running to equipment)
  10. Select Y‐Strainer (same size as main gas ball valve)
  11. Add (3) ¼” NPT dial (visual) pressure gauges 0‐30″ WC with ¼” NPT ball valve (rated for gas)
    1. (1) use for combustion air header
    2. (2) use before/after All‐In‐One Train Assembly
  12. Control Panels – contact Red‐Ray for design and pricing
  13. Automated burner control
    1. Temperature controller
    2. Motorized butterfly valve – Pyronics Flanged Butterfly Motorized Package Valves 1302 Data Sheet
      1. For system control – size based on main air header blower outlet
      2. For individual burner control – size based on mixer inlet
    3. Temperature measuring methods
      1. Thermocouple probe (used to measure ambient air)
      2. Optical pyrometer (used to measure product temperature)

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