Manufacturing method of honeycomb structure

A manufacturing method of a honeycomb structure comprising:

• a formed body forming step of extruding a forming raw material, to form a plurality of quadrangular prismatic columnar honeycomb formed bodies which have partition walls to define a plurality of cells forming through channels for a fluid and extending from one end face to the other end face and in which a formed body cross section perpendicular to a central axis is rectangular;
• a firing step of firing the honeycomb formed bodies, to form a plurality of quadrangular prismatic-columnar quadrangular segments;
• a triangular segment forming step of cutting parts of the formed quadrangular segments along a diagonal line in a quadrangular cross section perpendicular to the central axis and in parallel with the central axis, to form a triangular prismatic-columnar triangular segment which has a first side surface, a second side surface perpendicular to the first side surface, and an oblique side surface to couple side ends of the first side surface and the second side surface with each other and in which a triangular cross section perpendicular to the central axis is right-angled triangular;
• a bonded body forming step of disposing the triangular segment in a corner so that the oblique side surface becomes an outermost circumference and so that the residual first and second side surfaces face segment side surfaces of the quadrangular segments, respectively, to construct a temporary assembly in which a plurality of triangular segments and the quadrangular segments are combined, and interposing a bonding layer between the triangular segment and the quadrangular segment and between the quadrangular segments, to form a honeycomb bonded body;
• and
• a circumference grinding step of drying the obtained honeycomb bonded body, and then grinding and processing a circumferential surface of the honeycomb bonded body, to manufacture the honeycomb structure having a desirable shape,
• wherein the bonded body forming step further comprises:
• a pressurizing step of pressurizing the triangular segment from a circumferential direction of the temporary assembly toward a central direction thereof, by use of a pressurizing jig comprising a pressurizer which has a cross section having a shape analogous to that of the triangular cross section and a pressurizing oblique side surface abuttable on the oblique side surface, and a pressurizer driving portion which moves the pressurizer along a pressurizing direction perpendicular to the first side surface or the second side surface to pressurize the triangular segment in a state where the pressurizing oblique side surface abuts on the oblique side surface.