• Dual Twin Foaming Characteristics Test Apparatus

Dual Twin Foaming Characteristics Test Apparatus



Foaming of lubricating oils in applications involving turbulence, high speed gearing or high volume pumping can cause inadequate lubrication, cavitation, overflow and premature oxidation. The sample is blown with a controlled volume of air at different specified temperatures. The resultant foam is measured at the end of each aeration period and at different intervals afterward.

  • Dual-twin models for standard foaming characteristics tests
  • Automatic time sequence models for both tests
  • Custom configurations for specialized applications

Performs two tests at 75°F (24°C) and two tests at 200°F (93.5°C). Consists of two 12x18" (30.5x45.7cm) constant temperature baths with 1000mL test cylinders, certified diffusers, air delivery tubes, and flowmeters (94mL/min.) for each sample. Baths are equipped with microprocessor temperature controls, copper immersion heaters and 1⁄20hp circulation stirrers to maintain temperature uniformity of ±1°F (±0.5°C). Microprocessor PID control provides quick temperature stabilization without overshoot and the bath is protected by an over-temperature control circuit that interrupts power should bath temperature exceed a programmed cut-off point. Dual LED displays provide actual and setpoint temperature values in °C/°F format. Test cylinders are held securely in place by quick-locking cams in the bath cover assembly. A separate stainless steel support rack is provided to hold the test cylinders after removal from the bath. Cold bath (24°C) has built-in coils for circulating exit air from the high temperature test cylinders prior to passing to a volume meter, and a separate coil for circulating cooling water or refrigerant when the ambient temperature exceeds the test temperature. Supplied with rubber stoppers and glass air outlet tubes for each cylinder. Bath controls are enclosed in a finished steel base with chemical resistant polyurethane enamel finish. Communications software (RS232, etc.), ramp-to-set and other enhanced features are available as extra cost options. Contact your Koehler representative for information. 


FTM 791-3213 Aircraft Lubricants Test – Employs more severe conditions, smaller sample, increased air flow, and longer aeration period to test the foaming characteristics of aircraft-turbine lubricants. All models are available on special order for FTM 791-3213 testing. Please call or write for specifications and ordering information.

  • Test Cylinders, 1000mL (4)
  • Diffuser Stones, calibrated and certified (4)
  • Air Delivery Tube Assemblies (4)
  • Air Outlet Tubes (4)
  • Rubber Stoppers (4)
  • Bath Jars (2)
  • Support Rack (1)
  • Acrylic Safety Shield, 18"

Conforms to the specifications of: 

ASTM D892; IP 146; ISO 6247; DIN 51566; FTM 791-3211, 791-3213; NF T 60-129

Temperature Control: Digital Setpoint and switchable °C/°F displays

Built-in Over-temperature Cut-off Protection

Bath Temperature: 24°C (75°F), 93.5°C (200°F)

Air Flow Rate: 94mL/min

Bath Capacity: 9 gal (38.5L) each bath

    lxwxh,in.(cm)

    K43002/ K43092: 32 1⁄4x15x31 1⁄4 (82x38x79.4)
    K43003/ K43093: 32 1⁄4x15x31 1⁄4 (82x38x79.4)

    Net weight: 108 lbs (49.0 kg)

    Shipping Weight: 300 lbs (136.1 kg)

    Dimensions: 45x28x56 in. (114.3x71.1x142.2 cm)

    • 387-115-001 Air Pump 
    • K43025 Diffuser Stone Test Apparatus 
    • 250-000-12F ASTM 12F Thermometer  (or 250-000-12C ASTM 12C Thermometer)
    • K43026 Wet Test Gas Meter  (not required for Alternative Procedure)
    • 332-005-005 Drying Tower
    • K33031 Refrigerated Recirculator - Use with foam test baths for 24°C tests (Sequence I and III). Microprocessor based digital control and quiet running compressor provide reliable operation and accurate control within ±0.5°C. For complete specifications, please contact Koehler Customer Service. 115V 60Hz, 8A
    • K33032 Refrigerated Recirculator, 220-240V 50Hz, 4A
    • 250-000-12C ASTM 12C Thermometer. Range: –20 to +102°C
    • 344-100-01C Certified Diffuser Stone. Calibrated and certified for compliance with ASTM specifications for pore diameter and permeability
    • 344-100-001 Diffuser Stone, non-calibrated
    • 344-005-001 Stainless Steel ‘Mott’ Diffuser
    • 344-005-01C Stainless Steel ‘Mott’ Diffuser Certified