Lawler offers a wide range of heated baths for the oxidation of oil products by ASTM D4636, D5968, D6594, and FTM 791-5307/5308 methods. Each test position has a float in tube flowmeter with a precision control valve for the delivering up to 10 ±1 L/hr air to the test sample. Test methods specify flowmeter apparatus as 10 L/Hr but actual flowrates are 5 L/Hr in D4636 Alternate Proc. 2, D5968, and D6594. FTM 791-5308 states 3 L/Hr for spindle oils, 5 L/Hr all other oils. Upon request we can substitute the 10 L/Hr flowmeters with approx. 6 or 8.5 L/Hr flowmeters for increased precision at operating flowrates. A high limit controller(s) is also provided for each unit interrupting power to the heaters in the event of primary controller failure and over heating.

AVAILABLE MODELS:

Model HT-10-6 has 6 heated tube positions conforming to ASTM D4636 and related test methods. Each heated tube is of proper dimension to snugly fit the test tube. Each test position is individually temperature controlled with an indicating digital PID controller. Temperature stability of each position is ±0.5°C. Temperature range is from +50° to +400°C. Each tube’s temperature may be independently adjusted so as to assure each sample temperature in each test position is identical. It is energy saving since only the desired positions need to be operated. Model HT-10-6 has further flexibility allowing each test position to be at widely different temperatures. Each position is protected against overheating in the event of primary controller failure.

Model 419-4 is a 4 position dry aluminum block bath conforming to ASTM D4636 and related test methods. Upon request, Lawler can supply two independent blocks holding two samples each as shown in the photograph. The bench top cabinet holds both blocks separated by insulation. Each block has an independent digital display PID temperature controller. Each block may be operated at a different temperature from the other or remain unused to save energy. Inquire if this option is desired. Temperature stability and position to position uniformity within each block is ±0.5ºC (or better).

Model 419-6 is identical to 419-4, except it is a 6 position model.
 
We can accommodate requests for alternate numbers of positions. Please inquire.
 
Model 26 removes moisture from pressurized house air and is equipped with an electronic sensor measuring the dew point. The standard procedure of ASTM D4636 test method specifies that dry air with a dew point of -68°C be used for testing.

Model 33 humidifies air to 10 ±1 mg/L of air and is equipped with an electronic sensor measuring water content. Alternative Procedures 1 and 2 of ASTM D4636 test method may specify that humidified air be used for testing.