Seal structure

A method of (i) joining a first part and a second part to each other by inserting a fastener into an insertion hole of the second part and (ii) sealing, by using a seal material, between a first opposing surface of the first part and a second opposing surface of the second part, the first and second opposing surfaces being opposed to each other, the second part including

• a chamfered surface such that
• a first end of the chamfered surface is connected to an edge of the second opposing surface,
• a second end of the chamfered surface is connected to an edge of an end surface,
• the chamfered surface is inclined relative to the second opposing surface and the end surface, and
• when a diameter of the insertion hole is represented by D, in a direction perpendicular to a central axis of the insertion hole, the first end is located at a position away from the central axis of the insertion hole by one and a half times the diameter D or more, and the second end is located at such a position that a distance between the second end and the central axis of the insertion hole or between the second end and a line passing through central axes of a plurality of insertion holes is three times the diameter D or less, the method comprising:
• applying the seal material to one of the first opposing surface and the second opposing surface;
• making the first opposing surface and the second opposing surface be opposed to each other through the seal material;
• pressing the first opposing surface and the second opposing surface against each other and accommodating the seal material, protruding from between the first opposing surface and the second opposing surface, in a chamfered portion that is a space formed between the chamfered surface and the first opposing surface;
• inserting the fastener into the insertion hole;
• and
• fastening the fastener to join the first part and the second part to each other.