Emissivity of the one - plate lapping machine tool

A number of precision manufacturing applications use lapping process as a critical technology to achieve thickness tolerance and surface quality specification. Typical examples of the processed components are pump parts, transmission equipments, cutting tools, hydraulic and pneumatics, aerospace parts, inspections equipment, stamping and forging. Lapping leads to a surface with low roughness and high precision. It is carried out by applying loose abrasive grains between work and lap surfaces, and causing a relative motion between them resulting in material removal. The grains activities in the working gap cause also temperature rise of the executory system elements, including lap plate. Because of required parts accuracy tool flatness is the key to the successful machining. To avoid its excessive thermal expansion, plate temperature research was taken. Temperature is the most often measured physical quantity, second only to time. All advantages of infrared technology have led it to become frequently used technique for temperature measurement. It was also used by authors for lapping process observation. To assure accurate noncontact infrared temperature measurement there is a need to keep in mind several factors, including determining appropriate value of emissivity. Incorrectly, designated emissivity results in bigger measuring error. This work presents a method for determining wheel emissivity and its value obtained by presented way. To find emissivity of the lapping plate infrared camera V-20 II produced by VIGO System S.A. and contact thermometer TES1312 Dual K-Type were used. The experiments were carried out on a plate-lapping machine ABRALAP 380 with a grooved cast-iron lapping plate and three conditioning rings. The determined emissivity was equal 0.95 and was bigger than value from the table, as was expected. During lapping wheel surface is in fact very dark due to charging and covering the waste slurry. Obtained value will be used in future measurements.