| 摘要 |
Methods and apparatus for testing flammability properties of cellular plastics are described. Heat is applied to the underside of a heat-conductive plate on which is placed a specimen of the cellular plastic. A plurality of spaced-apart heat sensing devices are positioned below the specimen and in direct or close contact with the plate, one such heat sensing device being centrally positioned relative to the plate and serving as the setpoint sensor. A plurality of spaced-apart heat sensing devices are also disposed above the specimen and in direct or close contact with the top surface of the specimen, one such heat sensing device being centrally positioned relative to the top of the specimen. The sensing devices are adapted to provide signals convertible into information regarding the temperatures at their respective locations. At a preselected elevated temperature as sensed by the setpoint sensor, the time for the sensors on top of the specimen to sense a rise in temperature and/or to reach a preselected temperature is/are measured. Preferably, physical characteristics of the cellular plastic on completion of the test are also inspected.
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