ASTM D6320-99
(Test Method)Standard Test Methods for Single Filament Hose Reinforcing Wire Made from Steel
Standard Test Methods for Single Filament Hose Reinforcing Wire Made from Steel
SCOPE
1.1 These test methods cover testing of single filament steel wires that are used to reinforce hose products. By agreement, these test methods may be applied to similar filaments used for reinforcing other rubber products.
1.2 These test methods describe test procedures only and do not establish specifications or tolerances.
1.3 These test methods cover the determinations of the mechanical properties listed below:
Section Property
7-13 Breaking force (strength)
7-13 Yield strength
7-13 Elongation
14-20 Knot strength
21-27 Torsion resistance
28-34 Reverse bend
35-41 Wrap
42-48 Diameter
1.4 These test methods are written in SI units; the inch-pound units which are provided are not necessarily exact equivalents of the SI units. Either system of units may be used in these test methods. In the case of referee decisions, the SI units will prevail.
1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.
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Standards Content (Sample)
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Designation: D 6320 – 99
AMERICAN SOCIETY FOR TESTING AND MATERIALS
100 Barr Harbor Dr., West Conshohocken, PA 19428
Reprinted from the Annual Book of ASTM Standards. Copyright ASTM
Standard Test Methods for
Single Filament Hose Reinforcing Wire Made from Steel
This standard is issued under the fixed designation D 6320; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (e) indicates an editorial change since the last revision or reapproval.
1. Scope 3.1.2 elongation, n—the ratio of the extension of a material
to the length of the material prior to stretching.
1.1 These test methods cover testing of single filament steel
3.1.2.1 Discussion—Elongation may be measured at any
wires that are used to reinforce hose products. By agreement,
specified force or at rupture and is usually expressed in percent.
these test methods may be applied to similar filaments used for
3.1.3 hose wire, n—a monofilament steel wire with a
reinforcing other rubber products.
metallic coating, usually brass, used in a reinforced hose
1.2 These test methods describe test procedures only and do
product.
not establish specifications or tolerances.
3.1.4 torsion resistance, n—in hose reinforcing wire, the
1.3 These test methods cover the determinations of the
number of turns of twist in a specified length of wire that
mechanical properties listed below:
causes rupture.
Property Section
3.1.5 yield strength, n—the force at which a material
Breaking force (strength) 7-13
Yield strength 7-13
exhibits a specific limiting deviation from the proportionality
Elongation 7-13
of stress to strain.
Knot strength 14-20
3.1.5.1 Discussion—It is customary in this instance to
Torsion resistance 21-27
Reverse bend 28-34
express the deviation in terms of strain and to determine yield
Wrap 35-41
strength by the offset method, where a strain of 0.2 % is
Diameter 42-48
specified (see 11.11.1).
1.4 These test methods are written in SI units; the inch-
3.1.6 For definitions of other textile terms, refer to Termi-
pound units which are provided are not necessarily exact
nology D 123.
equivalents of the SI units. Either system of units may be used
in these test methods. In the case of referee decisions, the SI 4. Summary of Test Method
units will prevail.
4.1 A summary of the directions prescribed for determina-
1.5 This standard does not purport to address all of the
tion of specific properties of hose reinforcing wire is stated in
safety concerns, if any, associated with its use. It is the
the appropriate sections of the specific test methods that follow.
responsibility of the user of this standard to establish appro-
priate safety and health practices and determine the applica- 5. Significance and Use
bility of regulatory limitations prior to use.
5.1 The procedures for the determination of properties of
single-filament hose reinforcing wire made from steel are
2. Referenced Documents
considered satisfactory for acceptance testing of commercial
2.1 ASTM Standards:
shipments of this product because the procedures are the best
D 76 Specification for Tensile Testing Machines for Tex-
available and have been used extensively in the trade.
tiles
5.1.1 In the case of a dispute arising from differences in
D 123 Terminology Relating to Textiles
reported test results when using these test methods for accep-
D 2969 Methods for Testing Filaments, Strands, Cords, and
tance testing of commercial shipments, the purchaser and
Fabrics Made from Steel
supplier should conduct comparative tests to determine if there
is a statistical bias between their laboratories. Competent
3. Terminology
statistical assistance is recommended for investigation of bias.
3.1 Definitions:
As a minimum, two parties should take a group of test
3.1.1 breaking force, n—the maximum force applied to a
specimens which are as homogeneous as possible and which
material carried to rupture.
are from a lot of material of the type in question. The test
specimens then should be randomly assigned in equal numbers
These test methods are under the jurisdiction of ASTM Committee D-13 on
to each laboratory for testing. The average results from the two
Textiles and are the direct responsibility of Subcommittee D13.19 on Tire Cord and
laboratories should be compared by using an appropriate
Fabrics.
statistical test and an acceptable probability level chosen by the
Current edition approved March 10, 1999. Published June 1999. Originally
published as D6320–98. Last previous edition D6320–98. two parties before testing is begun. If a bias is found, either its
Annual Book of ASTM Standards, Vol 07.01.
NOTICE: This standard has either been superceded and replaced by a new version or discontinued.
Contact ASTM International (www.astm.org) for the latest information.
D 6320
cause must be determined and corrected or the purchaser and maximum force required to fracture the wire shall not exceed
supplier must agree to interpret future test results with consid- 90 % nor be less than 10 % of the selected force measurement
eration to the known bias. range. The specifications and methods of calibration and
verification shall conform to Specification D 76.
6. Sampling
10.2 In some laboratories, the output of CRE type of tensile
6.1 Lot Sample—As a lot sample for acceptance testing, testing machine is connected with electronic recording and
take at random the number of reels, coils, spools, or other computing equipment that may be programmed to calculate
shipping units of wire directed in an applicable material
and print the results for each of the force - extension properties,
specification or other agreement between purchaser and sup- optional.
plier. Consider reels, coils, spools, or other shipping units of
10.3 Extensometer, any device that can be attached to the
wire to be the primary sampling units. specimen and that permits recording of the specimen extension
during loading, optional.
NOTE 1—A realistic specification or other agreement between the
10.4 Grips, of such design that failure of the specimen does
purchaser and the supplier requires taking into account the variability
not occur at the gripping point, and slippage of the specimen
between and within primary sampling units, to provide a sampling plan
which at the specified level of the property of interest has a meaningful within the jaws (grips) is prevented.
producer’s risk and acceptable quality level.
11. Procedure
6.2 Laboratory Sample—Use the primary sampling units in
11.1 Select a proper force-scale range on the tensile testing
the lot sample as a laboratory sample.
machine based on the estimated breaking force of the specimen
6.3 Test Specimens— For each test procedure, take the
being tested.
number of lengths of hose reinforcing wire of the specified
11.2 If specified, tensile testing may be carried out after
lengths from each laboratory sample as directed in the test
aging for 1 h 6 5 min at 150 6 5°C (300 6 9°F).
procedure.
11.3 Set the crosshead speed at 25 mm/min. (1.0 in./min.)
BREAKING FORCE, YIELD STRENGTH, AND and recorder chart speed at 250 mm/min. (10 in./min.)
11.4 Adjust the distance between the grips of the tensile
ELONGATION
machine, nip to nip, to a gage length of 250 mm (10 in.), 6
7. Scope
0.5 %.
7.1 This test method covers the measurement of breaking 11.5 Secure the specimen in the upper grip sufficiently to
prevent slippage during testing. While keeping the specimen
force, yield strength, and elongation of single filament steel
reinforcing wire in a tensile test. straight and taut, place and secure the other end in the lower
grip.
8. Summary of Test Method
11.6 Apply a force of no greater than 1 N (0.2 lbf) on the
8.1 The specimen is clamped in a tensile testing machine clamped specimen to take out any residual slack before
initiating the test. This will be considered the zero-reference
and increasing forces applied until the specimen breaks. The
change in force is measured versus the increase in separation of point for elongation calculations.
11.7 Start the testing machine and record the force-
the specimen clamps to form a force-extension curve. Breaking
force is read directly from the curve and is expressed in extension curve generated.
11.7.1 If the specimen fractures at, or within, 5 mm (0.2 in.)
newtons (pounds - force). Elongation at break is the extension
at break divided by the original specimen length times 100. of the gripping point, discard the result and test another
specimen. If such jaw breaks continue to occur, insert a jaw
Yield strength the intersection of the force-extension curve
with a line at 0.2 % offset, is read from the force-extension liner, such as an abrasive cloth, between the gripping surface
and the specimen in a manner that the liner extends beyond the
curve and is expressed in newtons (pounds - force). Current
tensile test machines may have the capability for calculating grip edge where it comes in contact with the specimen.
elongation and yield strength using a programmed computer. 11.8 Conduct this test procedure on two specimens from
each laboratory sampling unit.
9. Significance and Use
11.9 Breaking Force— Read the maximum force from the
9.1 The load bearing ability of a reinforced rubber product force-extension curve.
such as a steel reinforced hydraulic hose is related to the 11.10 Elongation—Determine the elongation from the
strength of the single-filament wire used as the reinforcing force-extension curve.
material. The breaking force and yield strength are used in 11.11 Yield Strength— Determine the yield strength by the
engineering calculations when designing this type of reinforced 0.2 % offset method.
product. 11.11.1 On the force-extension curve (see Fig. 1) that has
been generated (see 11.7), lay off Om equal to the specified
9.2 Elongation of hose reinforcing wire is taken into con-
sideration in the design and engineering of hoses because of its value of the offset (0.2 % elongation): draw mn parallel to OA
and locate r. This intersection of mn with the force-extension
effect on uniformity and dimensional stability during service.
curve corresponds to force R, that is the yield strength. Should
10. Apparatus
the force-extension curve exhibit an initial nonlinear portion,
10.1 Tensile Testing Machine, constant rate of extension extrapolate from the straight line portion to the base line. This
(CRE) type tensile testing machine of such capacity that the intersection is point 0 used in this section.
NOTICE: This standard has either been superceded and replaced by a new version or discontinued.
Contact ASTM International (www.astm.org) for the latest information.
D 6320
ibility of this test method is being determined and will be
available before 2005.
14.2 Bias—The tensile property procedures of these test
methods have no bias, because these properties can be defined
only in terms of a test method.
KNOT STRENGTH
15. Scope
15.1 This section describes the test procedure to determine
the knot test characteristic of hydraulic hose wire with a
diameter less than or equal to 0.82 mm (0.032 in.). In practice,
the knot test is most suitable for wires less than 0.50 mm (0.020
in.).
FIG. 1 Force-Extension Curve for Determination of Yield Strength
16. Significance and Use
by the Offset Method
16.1 Complex stress and strain conditions sensitive to varia-
tion in materials occur in wire specimens during knot strength
12. Calculation
testing. The knot strength test is a useful tool in assessing wire
12.1 Break Strength— Calculate the average breaking force
ductility as defective wire lowers knot strength.
for each laboratory sampling unit to the nearest 1 N (0.2 lbf),
and record this value as breaking strength.
17. Apparatus
12.2 Elongation at Break:
17.1 Tensile Test Machine, CRE-type and grips as described
12.2.1 Calculate the elongation at break for each specimen
in Section 10. Electronic recording and computing equipment
from the force-extension curve to the nearest 0.1 %. Should the
is optional.
force-extension curve exhibit an initial nonlinear portion,
extrapolate from the straight line portion of the curve to the
18. Procedure
base line. This intersection is the point of origin for the
18.1 Select a proper force-scale range on the tensile testing
elongation determination. The extension from this point to the
machine based upon the estimated breaking force of the
force at the point of rupture is the total elongation.
specimen being tested.
12.2.2 Calculate the average elongation at break for each
18.2 If specified, the knot strength test may be carried out
laboratory sampling unit.
after aging for 1 h 6 5 min at 150 6 5°C (300 6 9°F).
12.3 Yield Strength— Calculate the average yield strength
18.3 Adjust the distance between the grips of the tensile
from each laboratory sampling unit as directed in Section
testing machine, nip to nip, to a gage length of 250 mm (10 in.)
11.11.1 to the nearest 1 N (0.2 lbf).
6 0.5 %.
18.4 Form a simple loop (overhand) knot in the middle zone
13. Report
of the test piece as shown in Fig. 2.
13.1 State that the tests were performed as directed in these
18.5 Center the knot between the grips. Secure one end of
test methods (D 6320) for breaking strength, elongation at
the specimen in the upper grip sufficiently to prevent slippage
break and yield strength. Describe the material or product
during testing. While keeping the specimen taut, place and
tested.
secure the other end in the lower grip.
13.2 Report the following information:
13.2.1 The test results of each specimen and the laboratory
sample average. Calculate and report any other data agreed to
between the purchaser and the supplier,
13.2.2 Type of tensile test machine, machine number (if
applicable), and rate of extension,
13.2.3 Whether specimens were heat aged or not,
13.2.4 Any deviation from the standard test procedure, and
13.2.5 Date of test and operator.
14. Precision and Bias
14.1 Precision—0.30 mm HT (high tensile: 2750 MN/m to
3050 MN/m ) brass plated hose wire was tested. The single
operator repeatability standard deviation for breaking force has
been determined to be 8.24N. The single operator repeatability
standard deviation for yield strength has been determined to be
5.24 N. The single operator repeatability standard deviation for
FIG. 2 Overhand Knot, (a) As Tied and (b) As Tightened During
elongation has been determined to be 0.14 %. The reproduc- the Test
NOTICE: This standard has either been superceded and replaced by a new version or discontinued.
Contact ASTM International (www.astm.org) for
...
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