GB/T 17657-2013 Test methods of evaluating the properties of wood-based panel and surface decorated wood-based panels compared with GB_T17657-1999, following is the main changes of technology content:

1.   Adding 17 items of testing method:

1)Adding 17 items of testing method: “measuring expansivity of thickness--- method 2”, “static bending strength and elastic modulus testing (four point bending)”, “ static bending strength measuring after soaking in water at temperature of 70℃ and 100℃，”“dampproof property testing --- testing in boiling water, ” “resisting peeling testing,” “testing for wear-resisting property of surface---- method 2”, “testing for wear-resisting property of surface--- method 3”, “ testing for accelerated ageing property”, “ resisting light - color fixing property”, “testing for colour difference”, “ testing for resisting dry and heat property--- method 2”, “ testing for resisting damp and heat property--- method 1”, “ testing for resisting damp and heat property of surface--- method 2”, “ testing for adhesive force of lacquer coating”, “testing for hardness of lacquer coating”, “testing for formaldehyde emission—1m³ climate box method”, “testing for formaldehyde emission--- gasometric analysis method”.

2) deleting 4 items of testing methods: “ testing for ultimate limited volume expansivity”, “testing for ultimate limited water absorption”, “testing for hardness”, testing for resisting ageing property”.

3) following is main changing of content:

• Measuring for size of test-piece:

Measuring item of thickness, pressure is changed from 0.02MPa to 0.02MPa---0.05MPa, diameter of parallel measuring head is 6.0mm---20.0mm.

• Testing for density:

Different size of test-piece, different measuring point of thickness, the point is at the distance of 25mm from two side changed to cross point of diagonal line of test-piece, adding requirement for size of hole shape, honeycomb shape, hollow structural plate test-piece.

• Measuring of rate of water content:

Deleting size of test piece, quality of test-piece should be not less than 20g, thickness of testpiece is thickness of plate, shape is not limited.

• Testing for expansivity of thickness after soaking---method 1:

Measuring time after soaking is changed from 30min to 10min

•  Static bending strength and elastic modulus testing (3 point bending)

Diameter of Loading and bearing roller is changed, adding testing for static bending strength and elastic modulus of squeezing plate honeycomb shape plate.

•  Testing for interal bonding strength:

“Internal bonding strength” is changed to “internal bonding ( combining ) strength”, much more detailed instruction of bonding condition for test-piece and blocking head, adding hard wooden blocking head and hard wooden bonding plate blocking head.

•  Testing for bonding strength of surface--- method 1

When thickness of test-piece is less than 10mm, adopting bonding with steel plate and other method to testing, changing internal diameter of ring groove and depth of groove.

•  Testing for bonding strength of suface--- method 2

When thickness is less than 8mm, adopting bonding steel plate testing method.

•   Testing of bonding strength

Test-piece is pretreated according to ISO 12466-1, 2007 bonding plate, quality of bonding, part1: testing method, adopting four conditions: cool water soaking for 24h, hot water soaking, boiling- dry- boiling, boiled in boiling water for 72h. Test-piece adopts requirement of ISO 12466-1:2007.

•   Testing for gripping screw force

Change size of test-piece, wring depth is total length of screw thread, clamper is changed.

•  Testing steadiness of size----method

Size of test-piece and clamper are changed.

• Testing for resisting-steam property of surface.

Adding metal wire test-piece frame, resisting-steam appearance of surfacee is divided into five level.

•   Testing for resisting-chapping of surface property

Level of chapping is changed from 3 to 5.

•  Testing for resisting- scratching property

Loading and revolution is set by standards of production

•  Testing for resisiting- polluted property –method 1

Range of pollutant is expanded, there are 6 kinds of pollutant, acetone, coffee, caustic soda(25% solution), aquae hydrogenii dioxidi(30% solution), shoe polish, citric acid(10% solution) is taken as routine testing pollutant, other pollutant for resisting-polluted property is not considered as reference.

• Testing for resisting-abrasion property--- method 1

Adding abrasive balance treatment and abrasive calibration, model NO. of abrasive is changed.

•  Testing for resisting tobacco-firing property of surface:

Primary standard prescribed tobacco is changed to any 3 domestic flue-cured tobacco.

• Testing resisting- dry and heat property of surface --- method 1

Heating medium is changed from glycerol to glyceryl stearate, size of container made of aluminum is changed, container made of aluminum filling with hot oil placed on surface of test-piece withno cover and so on.

• Testing resisting- impacting property :

Height of falling ball is set according standards of production, test piece is fixed on clamper or with undercourse, which is illustrated in standard of production for different production.

•  Testing for resisting – crack property

Size of test-piece and clamper are changed.

• Testing for amount of formaldehyde—boring hole method

Ablishing iodine method, adding blank space testing and treatment for quanlity controlling and other uses internal of enterprise. Temperature of water-bath and time are changed and so on. 

•  Testing for releasing amount of formaldehyde—dry container method

Adding blank space testing, testing consistence of background, adding balance treatment to test-piece, providing storage condition and time of formaldehyde absorption liquid. In calculating formula of releasing amount of formaldehyde, total superficial area of test-piece is changed to 1800cm², temperature of water bathing and time are changed.