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استاندارد ASTM D 1037 – 99 (بخش دوم)

 D 1037

9

fastener like a staple or roofing nail may be desired instead of a common

nail. If for any reason a different fastener than the common nail is used, the

report of the test shall describe the fastener actually used.

56. Specimens Tested in the Dry Conditions

56.1 When the tests are made in the dry state, the pullthrough

shall be made immediately after the nails have been

driven

 

 

57. Specimens Soaked Before Test

57.1 Specimens to be tested in the soaked condition shall be

prepared in accordance with Section 13, and the nails shall be

driven before the specimens are soaked.

58. Method of Loading

58.1 Modify the assembly for the direct withdrawal test

detailed in Fig. 11 by replacing the top pair of angles in the

specimen-holding fixture with a 6-in. (152-mm) length of 6 by

21⁄4-in. (152 by 57-mm) American standard channel. The web

of the channel shall have a 3-in. (76-mm) diameter opening

centered in the web. The edge of this opening provides the

support to the specimen during test. Center the specimenholding

fixture and attach it to the lower platen of the testing

machine. Insert the specimen in the holding fixture with the

point of the nail up. Grip the pointed end of the nail with a

tension grip or “Jacob’s-type drill chuck” which is attached to

the upper platen of the testing machine with a universal joint or

toggle linkage, to provide for automatic aligning. Apply loads

by separation of the platens of the testing machine. For other

Metric Equivalents

in. 1⁄16 1⁄8 3⁄16 3⁄8 1⁄2 5⁄8 3⁄4 7⁄8 1 11⁄8 11⁄4 21⁄4

mm 1.5 3 4.5 9 12.7 15 19 21 25.4 28 32 57

FIG. 9 Detail of Stirrups and Connections for Measuring the Resistance of Nails to Lateral Movement

FIG. 10 Test Assembly for Measuring the Resistance of Nails to

Direct Withdrawal

NOTE 1—1 in. = 25.4 mm.

FIG. 11 Details of Testing Equipment for Measuring the

Resistance of Nails to Direct Withdrawal

D 1037

10

types of fasteners than nails, it may be necessary to modify the

chuck or tension-grip type of loading fixture.

59. Speed of Testing

59.1 Apply the load to the specimen throughout the test by

a uniform motion of the movable head of the testing machine

at a rate of 0.06 in./min (1.5 mm/min) (see Note 8).

60. Test Data and Report

60.1 The maximum load required to pull the head of the nail

or other fastener through the board shall be the measure of

resistance of the material to nail-head pull-through, and shall

be included in the report. The report shall describe the type of

fastener used and the failure.

DIRECT SCREW WITHDRAWAL TEST

61. Scope

61.1 Screw-holding tests shall be made on screws threaded

into the board to measure the resistance to withdrawal in a

plane normal to the face. For numerous applications, the

withdrawal resistance of screws from the edge of the board is

desired. When that value is required the screw withdrawal

resistance in the plane parallel to the face shall be determined.

When general information is desired for comparing the screw

withdrawal resistance of a board with another board or

material, the No. 10, 1-in. (25-mm) Type AB sheet metal screw

(Note 25) shall be used. For special applications, however, this

procedure is adaptable to other sizes and types of screws.

62. Test Specimen

62.1 Withdrawal Perpendicular to the Plane of the Board

The test specimen shall be at least 3 in. (76 mm) in width by

4 in. (102 mm) in length. The thickness of the specimen shall

be at least 1 in. (25 mm) unless other considerations make it

desirable to test with the thickness as manufactured because

local bending of the board at withdrawal may affect test results.

If necessary, glue up two or more thicknesses of the board to

arrive at the 1-in. minimum thickness. One-inch, No. 10 Type

AB sheet metal screws (Note 25) shall be threaded into the

specimen 2⁄3 in. (17 mm). Lead holes shall be predrilled using

a drill 0.125 in. (3.2 mm) in diameter (Note 27).

62.2 Withdrawal from the Edge of the Board—The test

specimen shall be 3 in. (76 mm) in width by at least 6 in. (152

mm) in length and the thickness of the board as manufactured

(Note 26). One half of the test specimens shall be prepared

with the long dimension parallel and the other half with the

long dimension perpendicular to the long dimension of the

board in order to evaluate directional properties.A1-in., No. 10

Type AB sheet metal screw (Note 25) shall be threaded into the

edge of the board at midthickness 2⁄3 in. (17 mm). Lead holes

shall be predrilled using a drill 0.125 in. (3.2 mm) in diameter

(Note 27).

NOTE 25—Number 10 Type AB screws should have a root diameter

0.138 6 0.003 in. (3.51 6 0.1 mm) and a pitch of 16 threads per inch.

NOTE 26—In some applications where several thicknesses of hardboard

or the thinner particle board are laminated together, it may be desirable to

obtain the edge withdrawal resistance of a laminated board. When this is

done, the specimen shall be laminated from an odd number of thicknesses

and the screws shall be located at the midthickness of the center laminate.

NOTE 27—It is recognized that some other lead hole diameter may give

higher withdrawal resistance values for some densities and kinds of board.

Departures from this size of lead hole are permitted, but diameter used

shall be reported.

63. Specimens Tested in the Dry Condition

63.1 When the tests are made in the dry state, the withdrawals

shall be made immediately after the screws have been

embedded.

64. Specimens Soaked Before Test

64.1 Specimens to be tested in the soaked condition shall be

prepared in accordance with Section 13, and the screws shall

be embedded before the specimens are soaked.

65. Method of Loading

65.1 The assembly for the direct screw withdrawal is the

same as shown for direct nail withdrawal in Fig. 10. Attach the

specimen-holding fixture to the lower platen of the test

machine. Insert the specimen in the fixture with the heads of

the screws up as shown. Engage the heads of the screws by the

load-applying fixture equipped with a slot for easy attachment.

Attach this loading fixture to the upper platen of the testing

machine. Apply loads by separation of the platens of the testing

machine.

66. Speed of Testing

66.1 Apply the load to the specimen throughout the test by

a uniform motion of the movable head of the testing machine

at a rate of 0.6 in./min (15 mm/min) (see Note 8).

67. Report

67.1 The report shall include the following:

67.1.1 Diameter of lead hole actually used, indicating both

type and size of screw,

67.1.2 Any departures for other size of fastener,

67.1.3 Type of withdrawal, differentiated as surface (withdrawal

perpendicular to the plane of the board) or edge

(withdrawal parallel to the plane of the board) resistance,

67.1.4 Thickness of the board as actually tested, and

67.1.5 If the screw is broken rather than withdrawn, it shall

be noted and the test value shall not be included in those values

presented in the reports as values of withdrawal.

HARDNESS TEST

68. Scope

68.1 The modified Janka ball test shall be used for determining

hardness.

69. Test Specimen

69.1 Each specimen shall be nominally 3 in. (75 mm) in

width and 6 in. (150 mm) in length and at least 1 in. (25 mm)

thick. Because most boards are manufactured in thicknesses of

less than 1 in. (25 mm), the specimen for test shall be made by

bonding together several layers of the panel to make the

required thickness. A rubber cement or other suitable flexible

adhesive shall be used. The finished specimen shall be trimmed

D 1037

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after bonding so that edges are smooth. The dimensions of the

specimens as tested shall be measured to an accuracy of not

less than 60.3 %.

70. Procedure

70.1 Use of modified ball test with a “ball” 0.444 in. (11.28

mm) in diameter (100 mm2 projected area) for determining

hardness. Record as the measure of hardness the load at which

the “ball” has penetrated to one half its diameter, as determined

by an electric circuit indicator or by the tightening of the collar

against the specimen. The test assembly with a tool of the

tightening collar type is shown in Fig. 12.

71. Number of Penetrations

71.1 Make two penetrations on each of the two flat faces of

the board. Where one face is different than the other, as for

example the smooth face and wire-textured back of most

hardboards, report the data obtained from the two faces

separately. The locations of the points of penetration shall be at

least 1 in. (25 mm) from the edges and ends of the specimen

and far enough apart so that one penetration will not affect

another one.

72. Speed of Testing

72.1 Apply the load continuously throughout the test at a

uniform rate of motion of the movable crosshead of the testing

machine of 0.25 in./min (6 mm/min) (see Note 8).

73. Test Data and Report

73.1 The maximum load required to embed the “ball” to one

half its diameter shall be the measure of hardness, and shall be

included in the report.

HARDNESS MODULUS TEST

74. Scope

74.1 The hardness modulus method of determining “equivalent

Janka ball hardness” may be used for determining hardness

of building fiberboards and particle boards.

75. Significance and Use

75.1 The hardness modulus (in pounds per inch of penetration)

divided by 5.4 gives the equivalent Janka ball hardness in

pounds.7 The thinness of most wood-base panel materials

precludes the use of the regular Janka ball procedure (see

Methods D 143) unless several thicknesses are laminated

together to provide a thickness of about 1 in. (25 mm) or more.

75.2 This procedure is applicable for materials greater in

thickness than 1⁄8 in. (3 mm). For thicknesses 1⁄8 in. or less,

stacks of material may be used, but extreme care must be used

to select the proper slope for hardness modulus.

76. Test Specimen

76.1 Each specimen shall be nominally 3 in. (75 mm) in

width and 6 in. (150 mm) in length by the thickness of the

material. When materials are 1⁄4 in. (6 mm) or less in thickness,

an extra specimen shall be prepared as a backing material

during the test. The finished specimen shall be sawed square

with smooth edges. The dimensions of the specimens as tested

shall be measured to an accuracy of not less than 60.3 %.

77. Procedure

77.1 The rate of penetration of the modified Janka ball,

0.444 in. (11.3 mm) in diameter (100 mm2 projected area),

shall be used for determining hardness modulus. Suitable

modifications of the Janka ball hardness apparatus to measure

penetration are shown in Fig. 13 and Fig. 14. Fig. 13 shows the

modification manual measurements of penetration and Fig. 14

shows a cone unit with microformer for autographic recording.

Fig. 15 shows the kind of load-penetration data obtained from

tests. Each test shall be continued until the penetration is about

0.1 in. (2.5 mm). The slope of the straight-line portion of the

load penetration curve in pounds per inch shall be the hardness

modulus. The equivalent Janka ball hardness value in pounds is

obtained dividing this hardness modulus by the factor 5.4.

78. Number of Penetrations

78.1 At least two penetrations shall be made on each of the

two flat faces of each specimen. Where one face is different

from the other as, for example, the smooth face and wiretextured

back of most hardboards, the data obtained from the

two faces shall be reported separately. The locations of the

points of penetration shall be at least 1 in. (25 mm) from the

edges and ends of specimens and far enough apart so that one

penetration will not affect another one.

7 For further information on this relationship consult “Hardness Modulus as an

Alternate Measure of Hardness to the Janka Ball for Wood and Wood-Base

Materials,” by W. C. Lewis, U.S. Forest Service, research note FPL-0189, March

1968. Available from Forest Products Laboratory, One Gifford Pinchot Dr.,

FIG. 12 Janka Ball Test Apparatus for Hardness of Fiberboards Madison, WI 53705-2398.

D 1037

12

79. Speeding of Testing

79.1 The load shall be applied continuously throughout the

test at a uniform rate of motion of the movable crosshead of the

testing machine of 0.05 in./min (1.3 mm/min) (see 1.3).

80. Test Data and Report

80.1 The hardness modulus as determined from the loadpenetration

curve and the calculated equivalent Janka ball

hardness value shall be included in the report. When moisture

content or specific gravity, or both, are required, this shall be

determined as specified in Sections 127 and 128 and included

in the report.

SHEAR STRENGTH IN THE PLANE OF THE

BOARD

81. Scope

81.1 Shear strength tests shall be made on specimens

prepared by laminating each specimen so that the plane of the

FIG. 13 Janka-Ball Hardness Tool Equipped with a Micrometer Dial for Measuring Penetration

D 1037

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shear failure will be in the board proper and not in the glue

lines. This test, except for the method of preparing the

specimen, follows the procedure described in Section 90 to 94

of Methods D 143.

82. Test Specimen

82.1 The shear-parallel-to-plane of board tests shall be

made on 2 by 2 by 21⁄2-in. (50 by 50 by 63-mm) specimens

notched as illustrated in Fig. 16. It is the intent in this test to

have the plane of shear parallel to the surfaces of the board and

to have the failure approximately midway between the two

surfaces of the board. The specimen shall be glued up by

laminating sufficient thicknesses (Note 28) of the board together

to produce the desired 2-in. (50-mm) thickness of

specimen as shown in Fig. 16. The actual area of the shear

surface shall be measured.

NOTE 28—When the shear strength of a thin board like hardboard is

desired, it will be permissible to use a thicker material such as plywood for

outer laminations to reduce the total amount of gluing. When that

procedure is used, at least the center lamination and preferably the three

center laminations shall be of the board under test.

83. Procedure

83.1 Use a shear tool similar to that illustrated in Fig. 18 of

Methods D 143, providing a 1⁄8-in. (3-mm) offset between the

inner edge of the supporting surface and the plane, along which

failure occurs. Apply the load to, and support the specimen on,

the ends of the specimens as indicated by the large arrow in

FIG. 14 Janka-Ball Hardness Tool Adapted with Cone and Microformer Unit for Direct Autographic Recording of Load-

Penetration Data

 

D 1037

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Fig. 16. Take care in placing the specimens in the shear tool to

see that the crossbar is adjusted so that the edges of the

specimen are vertical and the end rests evenly on the support

over the contact area. Observe the maximum load only.

84. Speed of Testing

84.1 Apply the load continuously throughout the test at a

uniform rate of motion of the movable crosshead of the testing

machine of 0.024 in./min (0.61 mm/min) (see Note 8).

85. Test Failures

85.1 Record the character and type of failure. In all cases

where the failure at the base of the specimen extends back onto

the supporting surface, the test shall be culled.

86. Moisture Content

86.1 Use the portion of the specimen that is sheared off as a

moisture specimen.

GLUE-LINE SHEAR TEST (BLOCK TYPE)

87. Scope

87.1 The block-type glue-line shear test shall be used to

evaluate glued board constructions such as are obtained when

thicknesses are laminated together to provide a greater thickness

than when manufactured. When desired, the specimens

may be modified to evaluate glue lines between the test

material and solid wood or veneer by laminating the specimen

so that the glue line to be evaluated is so oriented in the

specimen that it coincides with the plane of shear in the

specimen. This test procedure is adopted from Test Method

D 905, except for the rate of loading (see 89.1).

88. Test Specimen

88.1 The test specimen shall be 2 in. (50 mm) in width and

2 in. in height, and shall be fabricated as shown in Fig. 17. The

specimen shall be from 1 to 2 in. (25 to 50 mm) thick, as

necessary, depending on the thickness of the board (Note 29).

Specimens shall be sawed from panels glued up in sizes of at

least 6-in. (152-mm) square. Care shall be taken in preparing

test specimens to make the loaded surfaces smooth and parallel

to each other and perpendicular to the glue line in the shear

plane. Care shall be exercised in reducing the lengths of the

laminations to 13⁄4 in. (44 mm) to ensure that the saw cuts

extend to, but not beyond the glue line. The width and height

FIG. 15 Typical Load-Indentation Lines Obtained with Autographic Equipment for Wood and Wood-Base Panel Materials. Values Shown

on Triangles Were Ones Used to Compute the Hardness Modulus Values

Metric Equivalents

in. 1⁄2 3⁄4 11⁄4 2 21⁄2

mm 12.7 19 31.7 51 63.5

FIG. 16 Shear Parallel to Surface Test Specimen

D 1037

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of the specimen at the glue line shall be measured to at least the

nearest 0.01 in. (0.25 mm). These measurements shall determine

the shear area.

NOTE 29—When the glue-line shear strength of a thin board like

hardboard is desired, it will be permissible to use a thicker material such

as plywood for outer laminations to reduce the total amount of gluing. The

material on either side of the glue line in the plane of shear shall be the

board under test unless the test involves a glue line of board and another

material.

89. Loading Procedure

89.1 Apply the load through a self-aligning seat to ensure

uniform lateral distribution of load. Apply the load with a

continuous motion of the movable head of the testing machine

at 0.024 in. (0.6 mm)/min. Use the loading tool required for the

shear in the plane of the board test, adjusted so that failure will

occur along or adjacent to the glue line (no offset), to load the

specimen. The shear tool is shown in detail in Fig. 1 of Test

Method D 905.

90. Test Failures

90.1 Report the shear stress at failure, based on the maximum

load, the overlap area between the two laminations, and

the percentage of fiber failure, for each specimen.

FALLING BALL IMPACT TEST

91. Scope

91.1 The falling ball impact test shall be used to measure the

impact resistance of boards from the kind of damage that

occurs in service when struck by moving objects. In this test a

2-in. (50-mm) diameter steel ball is dropped on a supported

panel of board from increasing heights, each drop being made

at the same point, the center, in the panel, until the panel fails.

The height of drop in inches that produces a visible failure on

the opposite face of the one receiving the impact is recorded as

the index of resistance to impact.

92. Apparatus

92.1 A suitable assembly for making the falling ball impact

test is shown in Fig. 18. Two frames of 11⁄2-in. (38-mm) thick

plywood, 9 by 10-in. (228 by 254-mm) outside dimension with

a 6-in. (152-mm) central square shall be provided with eight

3⁄8-in. (9-mm) carriage bolts for clamping the specimen between

the frames. The eight bolts shall be spaced equidistant on

and 85⁄8-in. (218-mm) diameter circle. A 2-in. (50-mm) diameter

steel ball (weighing 1.18 lb, 536 g) and a suitable means

of holding and releasing it from predetermined heights shall be

provided. During the test the frame and specimen shall be

supported solidly on a suitable base.

93. Test Specimen

93.1 The impact test specimens shall be 9 by 10 in. (228 by

254 mm) by the thickness of the material. No facing material

other than that which is a regular part of the board shall be

applied to the board prior to test.

94. Procedure

94.1 Before the test, clamp the specimen securely between

the frames. Drop the steel ball with an initial drop of 1 in. (25

mm) so that it strikes approximately at the center of the

specimen. Make repeated drops from increasing heights until a

visible fracture is produced on the top surface and on the

bottom surface of the specimen. Increments of drop shall be 1

in. (25 mm), measuring the distance from the bottom of the ball

to the top surface of the specimen. Record the heights of drop

that produce the visible fractures on the two surfaces. Catch the

ball after each drop so that there will be only one impact for

each drop.

95. Report

95.1 The report shall include the following:

95.1.1 Description of the failure,

95.1.2 Heights of drop that produced failures on each face,

and

Metric Equivalents

in. 1⁄4 1 13⁄4 2

mm 6 25.4 44 51

FIG. 17 Block-Type Glue-Line Shear Test Specimen

FIG. 18 Test Assembly for Falling Ball Impact Test

D 1037

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95.1.3 The measured thickness of each test specimen.

ABRASION RESISTANCE BY THE U.S. NAVY

WEAR TESTER

96. Scope

96.1 Abrasion resistance tests shall be made on the board to

determine the wear under simulated conditions of uniform

abrasion.

NOTE 30—Other test methods have been used to measure abrasion

resistance of other materials. The test method delineated here has been

used extensively for measuring the resistance of wood and other woodbase

materials like plywood to surface abrasion, so values are available for

comparing the resistance of wood-base fiber and particle panel materials

with the materials most commonly used alternately to them.8

97. Test Specimen

97.1 The area of the test specimen to be abraded shall be 2

by 3 in. (50 by 76 mm), and the specimen shall be fabricated

from a piece of the board 2 by 4 in. (50 by 101 mm) by the

thickness of the material (Note 31) as shown in Fig. 19. The

specimens shall be conditioned before test (see Section 6) and

the test made in the same conditioned atmosphere. The actual

dimensions of the abrading area of the specimen shall be

measured to the nearest 0.01 in. (0.2 mm). The thickness of the

test specimen shall be measured to at least the nearest 0.001 in.

(0.02 mm) near each corner and the center.

NOTE 31—When the board tested is less than 1⁄2 in. (12 mm) thick,

either sufficient thicknesses shall be laminated together to provide the

1⁄2-in. thickness or the specimen shall be backed by a thickness of wood

or plywood sufficient to provide the 1⁄2-in. total thickness of specimen

required.

98. Procedure

98.1 Conduct the test on the Navy-type abrasion machine9

as shown in Fig. 20, using as the abrading medium new No.

80-grit aluminum oxide, or equivalent. Apply the grit continuously

(Note 32) to the 14-in. (355-mm) diameter steel disk,

which serves as a platform supporting the specimen and rotates

at the rate of 231⁄2 r/min. Rotate the specimen in the same

direction as the steel disk at the rate of 321⁄2 r/min. Superimpose

a load of 10 lb (4.5 kg) on the test specimen. The machine

is designed so that twice each revolution the specimen is raised

1⁄16 in. (1.6 mm) above the steel disk and immediately lowered.

Determine the decrease in the thickness of the specimen at the

end of each 100 revolutions of the steel disk by measuring the

thickness of the specimen to the nearest 0.001 in. (0.02 mm)

near each corner and at the center, after brushing to remove any

dust or abrading material adhering to the surface of the

specimen. The mean of the five recordings shall be taken as the

loss in thickness. Repeat this procedure until the specimen has

500 revolutions of wear or as required (Note 33).

NOTE 32—The Navy wear tester is designed so that there is an excess

of grit on the abrading disk at all times. During all parts of the abrading

action, except when the specimen is in the raised position, the specimen

is pushing a small amount of grit ahead of it.

NOTE 33—When values of accumulated wear are plotted as ordinates

against revolutions, the slope of the curve is a straight line for wear

through uniform materials. When the rate of wear per 100 revolutions of

the abrading disk is not uniform after the first 200 revolutions, it is

probably due to a change in abrasion resistance with depth from the

original surface of the material being tested.

99. Report

99.1 The report shall include the following:

99.1.1 Loss in thickness in inches per 100 revolutions of

wear if uniform, and

99.1.2 If the amount of wear changes with depth from the

original, surface values for each 100 revolutions.

 

 

 
 
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