Method for inspecting pillar-shaped honeycomb formed body before firing or after firing
A method for inspecting a pillar-shaped honeycomb formed body before firing includes a step a1 of capturing at least one of a first end surface and a second end surface of a pillar-shaped honeycomb formed body before firing with a camera to generate an image of the at least one of the first end surface and the second end surface; a step b1 of measuring a size of an opening of a plurality of cells in the image generated by step a1; and a step c1 of identifying abnormal cells with the opening having a size deviating from a predetermined allowable range from the cells based on a measurement result of step b1, and measuring a number of the abnormal cells.
1. A method for inspecting a pillar-shaped honeycomb formed body before firing,
the pillar-shaped honeycomb formed body having a pillar-shaped honeycomb structure portion comprising an outer peripheral side wall and partition walls disposed on an inner peripheral side of the outer peripheral side wall, the partition walls partitioning a plurality of cells forming flow paths from a first end surface to a second end surface,
the method comprising:
a step a1 of capturing at least one of the first end surface and the second end surface of the pillar-shaped honeycomb formed body before firing with a camera to generate an image of the at least one of the first end surface and the second end surface;
a step b1 of measuring a size of an opening of the cells in the image generated by step a1; and
a step c1 of identifying abnormal cells with the opening having a size deviating from a predetermined allowable range from the cells based on a measurement result of step b1 and measuring a number of the abnormal cells.
2. The method according to claim 1 , wherein the size of the opening of each of the cells is based on a diameter of a maximum circle that can fit within the opening of each of the cells.
3. The method according to claim 1 , further comprising a step d1 of estimating a strength of the pillar-shaped honeycomb formed body after the pillar-shaped honeycomb formed body before firing is fired under predetermined conditions based on the number of the abnormal cells measured in step c1, using a correlation between the number of abnormal cells and strength of a plurality of other pillar-shaped honeycomb formed bodies after firing under the predetermined conditions, the correlation being obtained in advance for the other pillar-shaped honeycomb formed bodies having the same dimensions and the same composition as the pillar-shaped honeycomb formed body before firing.
4. The method according to claim 3 , wherein a correlation having a coefficient of determination (R 2 ) of 0.6 or more is used as the correlation when a linear regression equation is calculated.
5. The method according to claim 3 , wherein the strength is an isostatic crush strength.
6. A method for inspecting a pillar-shaped honeycomb formed body after firing,
the pillar-shaped honeycomb formed body having a pillar-shaped honeycomb structure portion comprising an outer peripheral side wall and partition walls disposed on an inner peripheral side of the outer peripheral side wall, the partition walls partitioning a plurality of cells forming flow paths from a first end surface to a second end surface,
the method comprising:
a step a2 of capturing at least one of the first end surface and the second end surface of the pillar-shaped honeycomb formed body after firing with a camera to generate an image of the at least one of the first end surface and the second end surface;
a step b2 of measuring a size of an opening of the cells in the image generated by step a2; and
a step c2 of identifying abnormal cells with the opening having a size deviating from a predetermined allowable range from the cells based on a measurement result of step b2 and measuring a number of the abnormal cells.
7. The method according to claim 6 , wherein the size of the opening of each of the cells is based on a diameter of a maximum circle that can fit within the opening of each of the cells.
8. The method according to claim 6 , further comprising a step d2 of estimating a strength of the pillar-shaped honeycomb formed body after firing based on the number of the abnormal cells measured in step c2, using a correlation between a number of abnormal cells and strength of a plurality of other pillar-shaped honeycomb formed bodies, the correlation being obtained in advance for the other pillar-shaped honeycomb formed bodies having the same dimensions and the same composition, and having been prepared under the same firing conditions as the pillar-shaped honeycomb formed body after firing.
9. The method according to claim 8 , wherein a correlation having a coefficient of determination (R 2 ) of 0.6 or more is used as the correlation when a linear regression equation is calculated.
10. The method according to claim 8 , wherein the strength is an isostatic crush strength.