Rule 153. Thermic Fluid heaters

a. All heaters shall be on such construction that coils are removable for periodic cleaning, visual inspection and hydraulic test. b. Suitable arrangement shall be made for cooling furnace effectively in case of failure. c. Before restarting the furnace, it shall be effectively purged. d. Velocity of flow of thermic fluid shall not be allowed to fall below the minimum recommended by the manufacturers while the heater is in operation. e. The thermic fluid shall be circulated in a closed circuit formation with an expansion cum deaerator tank. This tank shall be located outside the shed where the heater is installed. f. Every heater shall be provided with a photo-resister actuated audio-visual alarm indicate flame failure and automatic burner cut off. g. The stack temperature motor-cum-controller with audio visual alarm shall be provided so as to warn the operator in case the outlet temperature exceeds the specified min. h. Where inspection doors are provided on the furnace they shall be interlocked with the burner itself so that they cannot be opened until burner is shut off and furnace is cooled sufficient. i. All heaters shall also be provided with the following safety devices:-

(i) Level control in the expansion tank

(ii) Temperature control of thermic fluid

(iii) Differential pressure switch on the outlet line of the heater tubes and

(iv) Temperature control device for the fuel oil supply the burner. j. All devices mentioned in paragraph i shall have interlocking arrangement with burner so that in case of any predetermined limits being crossed the supply of fuel and air to burner shall automatically be cut-off. k. All safety interlocks when operated shall be indicated on the control panel of the heater by a suitable audio-visual alarm. l. Every heater unit shall be provided as a standard necessary an arrangement for sniffing with low pressure steam or nitrogen for putting out the fire. m. Electric panel for the heater shall be located near the heater but not so close as to be exposed to spilling or leaking oil. n. The heater shall be located in a place partitioned off with fire proof material from other manufacturing activities. o. Explosion vent shall be so installed that release takes place at safe location. p. The heater coil shall be subjected to pressure test by competent person once at least in every 12 months. This test pressure shall not be less than twice the operating pressure. q. If repairs are carried out to the coil, it shall be tested before taking it into use. r. The thermic fluid shall confirm to the specifications prescribed by the manufacturers and shall be tested by competent person for suitability atleast once in every three months period. Such test shall include test for acidity, suspended matter, ash contents, viscosity and flash point. s. Cleaning of internal surface of the heater or soot and check up of refractory surface on the inside shall be carried out every month or as often as required depending upon working conditions. The coils shall be removed and surface of the coils cleaned thoroughly once at least in a period of six months. The nozzles of filters and pumps shall be cleaned once a week during the period of use. t. A separate register containing the following information shall be maintained:

(i) Weekly checks carried out confirming the effectiveness of the interlock

(ii) Weekly checks confirming that all accessories are in goof state of repairs ; and

(iii) Information regarding fuel oil temperature, pressure thermic fluid inlet/ outlet pressure and temperature fuel gas temperature recorded at hourly interval. u. The heater when in operation shall always be kept in charge of a trained operator.