China Solid Wood Flooring Inspection and grading rules

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Solid Wood Flooring : OAK
Items	Face	Back
grae A	grade B	grade CD
Sound Knots	Ф＜3㎜ Length≤500㎜≤2pcs	Ф≤8mm Length≤500≤2pcs	Ф≤20㎜ Unlimited	Unlimited
Dead Knots	Not allowed	Ф≤4㎜ Length≤500≤1pcs	Ф≤10㎜≤5pcs	Ф≤20㎜ Unlimited
Worm Hole	Not allowed	Not allowed	Ф≤2㎜≤5pcs Must Puffy	Ф≤15㎜ Unlimited
Black Line	Not allowed	Unlimited	Unlimited	Unlimited
SAP wood	MAPLE Not allowed，BRICH Allowed	＜10﹪ of Area MAPLE，BRICH Allowed	MAPLE Unlimited，BRICH Allowed	MAPLE Unlimited，BRICH Allowed
Rot	Not allowed	Not allowed	Not allowed	Dot＜20﹪ of Area
Damage	Not allowed	Not allowed	Not allowed	Length≤ 30﹪ of length Width≤20﹪ of Width
Crack	Not allowed	Not allowed	0.1×15㎜≤2pcs	Width 0.5㎜ Length 50㎜ Unlimited
Wave Mark	Not allowed	Not allowed	Slightly	Unlimited
Press Mark	Not allowed	Not allowed	Slightly	Unlimited
Scratch	Not allowed	Very Slight	Slightly	Unlimited
Bubble	Not allowed	Not allowed	Not allowed	Unlimited
Lacquer Uneven	Not allowed	Not allowed	Not allowed	Unlimited
Pin	Not allowed	Ф≤0。5≤3pcs	Ф≤0。5≤3pcs	Unlimited
Orange Peal	Not allowed	Not allowed	≤5﹪ of Area	Unlimited
Rough	≤5pcs	≤8pcs	≤8pcs	Unlimited

Milling Tolerance

Bending	Short	Length≤500㎜, allowed≤0.02﹪ of length, Length≥500㎜，allowed≤0.03﹪ of length
Cupping	Bending≤0.2﹪ of width, Cupping≤0.15% of width
Banana	≤0.3% of length
Gap	≤0.1㎜
High-Low Difference	≤0.2㎜

Others: MC: 7%≤MC≤EMC; Varnish adherence: A grade 0-1; B grade 2; Varnish Hardness is up to customer’s request.

Oak 3-layer 3-strip Engineered flooring quality standard
Location	Defects	Grade A	Grade B	Grade CD
Face Veneer	Live knot	Diameter ≤ 2mm; sparse	Diameter ≤ 5mm; sparse	Diameter ≤ 15mm; sparse
Dead knot	Not allowed	3 allowed, diameter ≤ 3mm	3 allowed, diameter ≤ 10mm
Sapwood	Not allowed	Not distinct, natural and harmonic	≤ 25% of plank’s area; ≤ 4-6 pieces (mending)
Colour Variation	Natural and harmonic	Slight	Low contrast
Rot	Not allowed	Slight	Slight
Inbark	Not allowed	Not allowed	Light and natural, 2 allowed, diameter ≤ 20mm
Pith	Not allowed	Not allowed	Not allowed
Retrorse veins	Not allowed	Slight	Allowed
Crack	Not allowed	Not allowed	Slight, 1 allowed, diameter ≤ 3mm (mending)
Veins	FQ mixed	FQ mixed	FQ mixed
Black/Blue spot	Not allowed	Not allowed	Slight
Brown line	Not allowed	Not allowed	Allowed
Dimension shortness	Not allowed	Not allowed	Not allowed
Glue stains	Not allowed	Not allowed	Slight
Wormholes	Not allowed	Not allowed	2 allowed, diameter ≤ 2mm (mending)
Indentation	Not allowed	Not allowed	Slight
Strong wooden lump	Not allowed	Slight	Slight
Discolouration	Not allowed	Not allowed	Slight, natural
Resin pocket	Not allowed	Not allowed	Length < 1mm
Wane	Not allowed	Not allowed	Slight
Wood abnormality	Not allowed	Not allowed	Slight
Face veneer gap	Transverse	0.1mm	0.2mm	0.2mm
Lengthwise	0.1mm, length > 10mm	0.2mm, length > 200mm	0.2mm, length > 300mm
Middle Layer	Middle layer gap	3mm	3mm	3mm
Rot	Slight, no fall off	Slight, no fall off	Slight, no fall off
Tongue missing	≤ 20mm (cumulative) ≤ 1% of plank’s length	≤ 20mm (cumulative) ≤ 1% of plank’s length	≤ 30mm (cumulative) ≤ 3% of plank’s length
Destruction of ends	Not allowed	Slight	≤ 2mm each end
Back Veneer	Bore hole	Diameter ≤ 30mm	Diameter ≤ 30mm	Diameter ≤ 30mm
Dead knot	No fall off	No fall off	Allowed
Wormholes	Few	Slight	Mild
Inbark	Slight	Slight	Allowed
Cymbate and round mending	≤ 5% of plank’s area	≤ 10% of plank’s area	Allowed
Dry crack	Slight	Slight	Length ≤ 1000mm; width ≤ 10mm
Lack of sanding	Slight	Slight	Allowed
Varnish	Putty mending mark	Not allowed	Not allowed	Slight
Varnish stains	Not allowed	Not allowed	Slight
Light not even	Not allowed	Not allowed	Slight
Varnish protruding over the edge	Not allowed	Not allowed	Slight
Scratches /Exposed undercoat	Not allowed	Not allowed	Slight
Varnish not even	Not allowed	Not allowed	Slight
Others	Tongue deflection	Not allowed	Not allowed	Not allowed
Roughness of the tongue and groove	Not allowed	Not allowed	Slight
Wanting arris	Not allowed	Not allowed	Slight
Joining of tongue and groove	Good fit	Good fit	Good fit
Cup warping concave	Not allowed	Chord ≤ 0.15% of plank’s width	Chord ≤ 0.15% of plank’s width
Cup warping convex	Chord ≤ 0.20% of plank’s width	Chord ≤ 0.20% of plank’s width	Chord ≤ 0.20% of plank’s width
Bow warping concave	Chord ≤ 0.10% of plank’s length	Chord ≤ 0.10% of plank’s length	Chord ≤ 0.20% of plank’s length
Bow warping convex	Chord ≤ 0.50% of plank’s length	Chord ≤ 1% of plank’s length	Chord ≤ 1% of plank’s length
Height difference	0.1mm	0.1mm	0.1mm
Roughness of ends	Not allowed	Not allowed	Slight
Tolerance on Dimensions	Length (+/-) 1mm,Width (+/-) 0.1mm,Thickness (+/-) 0.1mm,Gap 0.1mm

Oak  1-strip quality Standard
Location	Defects	GradeA	Grade B	Grade C	Grade D
Face Veneer	Live knot	Diameter ≤   2mm ; sparse	Diameter ≤   5mm ; sparse	3 allowed, diameter ≤   10mm	Not restricted
Dead knot	Not allowed	2 allowed, diameter ≤   2mm	2 allowed, diameter ≤   5mm , sparse	3 allowed, diameter ≤   15mm , sparse
Sapwood	Not allowed	Not distinct, natural and harmonic	≤  5% of plank’s width (mending)	≤  30% of plank’s width (mending)
Colour variation	Not allowed	Not allowed	Slight and natural	Natural and harmonic, low contrast
Rot	Not allowed	Not allowed	Not allowed	Not allowed
Inbark	Not allowed	Not allowed	Not allowed	2 allowed, length ≤   15mm ; width ≤   4mm (mending)
Pith	Not allowed	Not allowed	Not allowed	Not allowed
Crack	Not allowed	Not allowed	Not allowed	Not allowed
Brown line	Not allowed	Not allowed	2 allowed, sparse length ≤   15mm ; width ≤   3mm	4 allowed, length ≤   30mm ; width ≤   5mm
Stains	Not allowed	Not allowed	Not allowed	Not allowed
Wormholes	Not allowed	Not allowed	Not allowed	5 allowed, sparse diameter ≤   2mm (mending)
Plinth mark	Not allowed	Not allowed	Not allowed	Not allowed
Discolouration	Not allowed	Not allowed	Not allowed	Slight and natural
Wane	Not allowed	Not allowed	Not allowed	Not allowed
Middle Layer	Middle Layer Gap	3mm	3mm	3mm	3mm
Rot	Slight, no fall off	Slight, no fall off	Slight, no fall off	Slight, no fall off
Tongue missing	≤   20mm (cumulative) ≤  1% of plank’s length	≤   20mm (cumulative) ≤  1% of plank’s length	≤   20mm (cumulative) ≤  2% of plank’s length	≤   30mm (cumulative) ≤  3% of plank’s length
Destruction of ends	Not allowed	Not allowed	Slight	≤   2mm each end
Back Veneer	Bore hole	Diameter ≤   30mm	Diameter ≤   30mm	Diameter ≤   30mm	Diameter ≤   30mm
Dead knot	No fall off	No fall off	No fall off	Allowed
Wormholes	Few	Few	Slight	Mild
Inbark	Slight	Slight	Slight	Allowed
Cymbate and round mending	≤  5% of plank’s area	≤  5% of plank’s area	≤ 10% of plank’s area	Allowed
Dry crack	Slight	Slight	Slight	Length ≤   1000mm ; width ≤   10mm
Lack of sanding	Slight	Slight	Slight	Allowed
Varnish	Putty mending mark	Not allowed	Not allowed	Not allowed	Slight
Varnish stains	Not allowed	Not allowed	Not allowed	Slight
Light not even	Not allowed	Not allowed	Not allowed	Slight
Varnish protruding over the edge	Not allowed	Not allowed	Not allowed	Slight
Scratches /Exposed undercoat	Not allowed	Not allowed	Not allowed	Slight
Varnish not even	Not allowed	Not allowed	Not allowed	Slight
Others	Tongue deflection	Not allowed	Not allowed	Not allowed	Not allowed
Roughness of the tongue and groove	Not allowed	Not allowed	Not allowed	Slight
Wanting arris	Not allowed	Not allowed	Not allowed	Slight
Joining of tongue and groove	Good fit	Good fit	Good fit	Good fit
Cup warping concave	Not allowed	Not allowed	Chord ≤  0.15% of plank’s width	Chord ≤  0.15% of plank’s width
Cup warping convex	Chord ≤  0.20% of plank’s width	Chord ≤  0.20% of plank’s width	Chord ≤  0.20% of plank’s width	Chord ≤  0.20% of plank’s width
Bow warping concave	Chord ≤  0.10% of plank’s length	Chord ≤  0.10% of plank’s length	Chord ≤  0.10% of plank’s length	Chord ≤  0.20% of plank’s length
Bow warping convex	Chord ≤  0.50% of plank’s length	Chord ≤  0.50% of plank’s length	Chord ≤  1% of plank’s length	Chord ≤  1% of plank’s length
Height difference	0.05mm	0.05mm	0.05mm	0.05mm
Roughness of ends	Not allowed	Not allowed	Not allowed	Slight
Tolerance on dimensions	Length (+/-) 1mm ,Width (+/-) 0.1mm ,Thickness (+/-) 0.1mm ,Gap 0.1mm

ORDERING DETAILS

MINIMUM ORDER: 200SQ.M

DELIVERY TIME: ABOUT 25 DAYS

SAMPLE AVAILABLE: SMALL PIECES OF SAMPLES FREE OF CHARGE; FULL LENGTH SAMPLES SHOULD BE PAID BEFORE EXPRESSING.

QUALITY CONTROLLING

PROTECTING PRODUCTS-RANDOMLY SELECTS CARTONS TO BE INSPECTED PLANK STABILITY-VERIFY MOISTURE CONTENT SCRATH RESISTANT-TEST VARNISH HARDNESS RESISTANCE AGAINST FLAKING-TEST VARNISH ADHERENCE FITTEST SPECIFICATION-VERIFY VARNISH BRIGHTNESS AND PRECISION MEASURES TO EACH PLANK AND ITS COMPONENT PARTS.