Categories of defects | Inspection Item | Face | Back |
| Grade Of Plywood |
| AA Grade | A Grade | B Grade | C Grade |
| (1)Pin knots | | Allowed |
| (2)Inter grown knots | maximal single diameter (mm) | 10 | 20 | Not Restricted |
| (3)partially inter grown knots, dead knots, inbark | the entries on one side per square meter | Not allowed | 3 | 4 | 6 | Not Restricted |
| | partially inter grown knots | maximal single diameter (mm) | Not allowed | 10 25
(not counted up to 5) | Not Restricted |
| Dead knots | maximal single diameter (mm) | Not allowed | 4
(not counted up to 2) | 6
(not counted up to 4) | 15 | 50 |
| Inbark | maximal single length (mm) | Not allowed | 15
(not counted up to 5) | 30
(not counted up to 10) | Not Restricted |
| (4)Abnormal structure | | Allowed |
| (5)Split | maximal single width (mm) | Not allowed | 1
Basswood:0.5
Southern Timber:1.5 | 1.5
Basswood:1
Southern Timber:2 | 3
Basswood:1.5
Southern Timber:4 | 6 |
| maximal single length (mm) | 200
Southern Timber:250 | 300
Southern Timber:350 | 400
Southern Timber:450 | Not Restricted |
| (6)Worm holes,dog holes,holes | maximal single diameter (mm) | Not allowed | 2 | 4 | 8 | 15 |
| the entries on one side per square meter | 4 | 4(not counted up to 2mm) | Not Sifter Shape Appearence，Not Restricted |
| (7)Discoloration | Not exceed the area of side(%) | Not Allowed | 5 | 25 | Not Restricted |
Note: ①Tint fleck streaks is counted as discoloration；
②A grade: fuscous fleck streaks not exceed 20mm in length and 2mm in width;
③B grade: fuscous fleck streaks not exceed 150mm in length and not exceed 3 spots per m2
④Basswood Board(except AA grade),false heartwood is allowed ,but the color and luster of the A grade should be attempered
⑤Basswood board (A gradee),brown or black pith flecks are not allowed;
⑥(AA grade) limbic heartwood of different color are counted as discoloration |
| (8)Rot | | Not allowed | Symbols of incipient decay are allowed if not affect strength ,yet the area not exceed 1% of the side area | incipient decay is allowed but the veneer of this part will not flake off,also can't be twisted into powder |
| (9) outer ply open joint | Max. single width(mm) | Not allowed | 0.5 | 1 | 2 |
| Max. single length account for the length of the panel (%) | 10 | 30 | 50 |
| Bar /metre in width | 1 | 2 | Not restricted |
| (10) outer ply overlap | Max single width(mm) | Unallowed | 8 | Not restricted |
| Max. single length account for the length of the panel (%) | 20 |
| (11)Core gap | The core gap appressed to outer ply | Max single width(mm) | Not allowed | 2 | 4 | 8 | 10 |
| Bar /metre in width | 2 | 3
(not counted up to 2mm) | Not restricted |
| The max gap width of other ply(mm) | 10 |
| (12)centers gap | Max single width (mm) | Not allowed | 10 |
(13) blister, delamination | | Not allowed |
(14)Hollow, imprint,bump | Max. single area(mm2) | Not allowed | 50 | 400 | 3000 | Not restricted |
| the entries on one side per square meter | 1 | 4 | Not restricted |
| (15) torn grain | Not exceed side area(%) | Not allowed | 1 | 3 | 25 | Not restricted |
| The depth not exceed(mm) | 0.4 | Not penetrate through, allowed |
| (16)outer ply sanding through | Area on side per mm2 | Not allowed | 1000 | Not restricted |
| (17)glue penetration & any other manmade stain | Not exceed side area(%) | Not allowed | 0.5 | 3 | 30 | Not restricted |
| (18)patch、shim | Allowed(If made in proper way and fill up durably),the entries on side per m2 | Not allowed | 3 | Not restricted | Not restricted |
| add up to not exceed side area(%) | 0.5 | 3 |
| Gap not exceed(mm) | 0.5 | 1 | 2 |
| (19)aluminous inclusions | | Not allowed | allowed |
| (20)defects at the edges of the panel | Not exceed mm(within the nominal breadth) | Not allowed | 5 | 10 |
| (21)other defects | | Not allowed | Regarded as the most similar defects |
