Method of manufacturing tubular member for exhaust gas treatment device, and coating film forming device

A method of manufacturing a tubular member for an exhaust gas treatment device, the tubular member including a tubular main body made of a metal and an insulating layer formed on at least an inner peripheral surface of the tubular main body, the insulating layer containing glass,

• the method comprising steps of:
• forming a coating film by spraying a coating liquid for insulating layer formation onto the inner peripheral surface of the tubular main body;
• and
• firing the coating film to obtain the insulating layer,
• wherein the tubular main body is subjected to heating at a heating temperature of 50° C. to 120° C.;
• and
• the spraying is performed while the tubular main body subjected to heating is rotated with a length direction thereof being a rotation axis.