QC/T 639-2004 PDF in English
QC/T 639-2004 (QC/T639-2004, QCT 639-2004, QCT639-2004)
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Rubber weatherstrips for automobile
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| QC/T 639-2000 | English | 199 |
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QC/T 639-2004: PDF in English (QCT 639-2004) QC/T 639-2004
AUTOMOTIVE INDUSTRY STANDARD
OF THE PEOPLE’S REPUBLIC OF CHINA
Replacing QC/T 639-2000, QC/T 640-2000
Rubber Weatherstrips for Automobile
ISSUED ON: OCTOBER 20, 2004
IMPLEMENTED ON: APRIL 01, 2005
Issued by: National Development and Reform Commission
Table of Contents
Foreword ... 3
1 Scope ... 4
2 Normative References ... 4
3 Requirements ... 5
4 Test Methods ... 9
5 Inspection Rules ... 11
6 Marking, Package, Transportation and Storage ... 13
Appendix A (Normative) Corrosivity Test Method of Rubber Weatherstrips ... 15
Appendix B (Normative) Low-Temperature Property Test Method of Rubber
Weatherstrips ... 18
Appendix C (Normative) Test Method for Breakout Force between Dense
Rubber and Sponge Rubber of Rubber Weatherstrips ... 20
Appendix D (Normative) Test Method for Binding Force between Connector
and Connection Angle of Rubber Weatherstrips ... 23
Appendix E (Informative) Classification of Rubber Weatherstrips for
Automobile ... 25
Foreword
This Standard replaced QC/T 639-2000 Buses - Rubber Sealing Strips of Doors and
Windows, and QC/T 640-2000 Buses – Flocking Sealing Strips of Doors and Windows.
Compared with QC/T 639-2000 and QC/T 640-2000, this Standard has the major
changes as follows:
--- Combine the two standards into the one standard; change the standard name
into Rubber Weatherstrips for Automobile;
--- Add the Appendixes A, B, C, D and E.
--- Add product length table without tolerance;
--- Add “corrosivity”, “water resistance” items to the properties of the rubber;
--- Delete “tear performance” item from the properties of the rubber;
--- Add three hardness range of the rubber of 50±5, 80±5, 90±5 to the properties of
the rubber; and improve the original index;
--- Replace the expression of oxygen concentration of ppm by 10-6;
--- Add 11 items for the performance of the finished products; and the corresponding
standards of the test methods.
Appendixes A, B, C, and D of this Standard are normative; while Appendix E is
informative.
This Standard was proposed by National Technical Committee for Standardization of
Automobile.
This Standard shall be under the jurisdiction of National Technical Committee for
Standardization of Automobile.
Drafting organizations of this Standard: Shanghai SAIC-METZELER Sealing Systems
Co., Ltd.; Beijing Wanyuan Gdx Automotive Sealing Products Co., Ltd.; Guizhou
Guihang Automobile Parts Co., Ltd. Hongyang Seal Components Corporation; Tianjin
Xingguang Rubber Plastic Co., Ltd.; Chongqing Yifeng Automobile Sealing Strips Co.,
Ltd.; Xiamen Baiji Sealing Element Co., Ltd.; and Hubei Konx Automobile Sealing
Strips Co., Ltd.
Chief drafting staffs of this Standard: Chen Haiyan, Ma Junli, Hu Zhugeng, Hao Jie,
Deng Mingxiang, He Wenbing, and Yu Gangli.
Rubber Weatherstrips for Automobile
1 Scope
This Standard specifies the technical requirements, test methods, inspection rules,
marking, package, transportation and storage of rubber weatherstrips for automobile.
This Standard is applicable to the various weatherstrips for automobile manufactured
by the base material of EPDM rubber.
2 Normative References
The provisions in following documents become the provisions of this Standard through
reference in this Standard. For dated references, the subsequent amendments
(excluding corrigendum) or revisions do not apply to this Standard, however, parties
who reach an agreement based on this Standard are encouraged to study if the latest
versions of these documents are applicable. For undated references, the latest edition
of the referenced document applies.
GB/T 528-1998 Rubber, Vulcanized or Thermoplastic - Determination of Tensile
Stress-Strain Properties (eqv ISO 37:1994)
GB/T 531-1999 Rubber - Determination of Indentation Hardness by Means of
Pocket Hardness Meters (idt ISO 7619:1986)
GB/T 1682-1994 Rubber, Vulcanized - Determination of Low-Temperature
Brittleness (Single Test Piece Method) (eqv ISO 812:1991)
GB/T 2828.1-2003 Sampling Procedures for Inspection by Attribute – Part 1:
Sampling Schemes Indexed by Acceptance Quality Limit (AQL) for Lot-by-Lot
Inspection (idt ISO 2859-1:1999)
GB/T 2941-1991 Standard Temperature, Humidity and Time for Environmental
Regulation and Testing of Rubber Samples (eqv ISO 471:1983)
GB/T 3511-2001 Rubber, Vulcanized and Thermoplastic - The Test Method of
Resistance to Direct Natural Weathering (neq ISO 4665:1998)
GB/T 3512-2001 Rubber, Vulcanized or Thermoplastic - Accelerated Ageing and
Heat Resistance Tests - Air-Oven Method (eqv ISO 188:1998)
GB/T 3672.1-2002 Rubber - Tolerances of Products - Part 1: Dimensional
Tolerances (idt ISO 3302-1:1996)
GB/T 5721-1993 General Rules of Identification, Packaging, Transportation and
Storage for Rubber Sealing Products
GB/T 7759-1996 Rubber, Vulcanized or Thermoplastic - Determination of
Compression Set at Ambient Elevated or Low Temperatures (eqv ISO 815:1991)
GB/T 7762-2003 Rubber, Vulcanized or Thermoplastic - Resistance to Ozone
Cracking - Static Strain Test (eqv ISO 1431-1:1989)
GB/T 8170-1987 Rules of Rounding off for Numerical Values
GB/T 9868-1988 Rubber - General Directions for Achieving Elevated or
Subnormal Temperatures for Test Purposes (idt ISO 3383-1985)
GB/T 12831-1991 Rubber, Vulcanized - Test Method of Resistance to Artificial
Weathering (Xenon Lamp) (neq ISO 4665-3:1987)
GB/T 19243-2003 Rubber, Vulcanized or Thermoplastic - Methods of Test for
Staining in Contact with Organic Material (idt ISO 3865:1997)
HG/T 2369-1992 Technical Conditions on Rubber Plastic Tensile Testing Machine
HG/T 3055-1988(1997) Latex Foam - Determination of Apparent Density (eqv ISO
845:1997)
HG/T 3090-1987(1997) General Rules of Visual Quality for Moulded and Extruded
Rubber Products
QC/T 709-2004 Test Method of Compression Set for Automobile Weatherstrips
QC/T 710-2004 Test Method of Compression Load for Automobile Weather-Strips
QC/T 711-2004 Test Method of Abrasion of Flock for Automotive Weather-Strips
QC/T 716-2004 Retention Strength and Insertion Resistance Test Method for
Automobile Weatherstrips
3 Requirements
3.1 General requirements
The weatherstrips shall be manufactured in accordance with technical document
approved by the specified procedures. If the user has other special requirements, it
shall be determined through the negotiation between the supplier and the purchaser.
3.2 Appearance
3.2.1 The appearance for the dense rubber of the weatherstrips shall conform to the
relevant provisions of HG/T 3090-1987(1997). The appearance for the sponge rubber
shall be free of the defects that may affect the appearance and use performance of the
products, such as bubbles, cracked skin, broken skin, lack of rubber, etc.
3.2.2 The flocked surface is evenly flocked; the surface is clean, no stains; and the
substrate is not allowed to be exposed.
3.2.3 The special requirements shall meet the requirements of the approved sealed
sample or sample determined through the negotiation between the supplier and the
purchaser.
3.3 Specification size
3.3.1 The shape and size of the cross-section of product shall be within the tolerance
range of control chart with a magnification of 10. If the drawings have no explicit
requirements, it can be performed as per GB/T 3672.1-2002.
3.3.2 The length size and tolerance of the products shall conform to the relevant
provisions of the product drawings. The tolerance that is not indicated can be
performed as per Table 1.
Table 1 Unindicated Tolerance mm (except those indicated otherwise)
3.4 Materials
3.4.1 The substrate material of the weaterstrips take the rubber compound with EPDM
as the main raw material; the rubber properties shall meet the requirements of Table
2.
3.4.2 The auxiliary materials (such as fluff, skeleton material, etc.) of weatherstrips
shall conform to the relevant provisions of the product drawings.
Size
Tolerance Tolerance
Size Dense
rubber/compound
composition
Dense
rubber/compound
composition
Sponge rubber Sponge rubber
Greater than
4000
Table 2 – Rubber Properties
3.5 Properties of finished products
The properties of finished products shall meet the requirements of Table 3.
Table 3 – Properties of Finished Products
Items Property index Test method
Compression set [(70±2) °C/96h], % As per requirements of drawings 4.4.2
Compression load (squeezing force), N As per requirements of drawings 4.4.3
Insertion force, N As per requirements of drawings 4.4.4
Withdrawal force, N As per requirements of drawings 4.4.4
Low-temperature property [(-40±2) °C/24h] Still be elastic, no cracks 4.4.5
Breakout force between dense rubber and
sponge rubber, N ≥100 4.4.6
Binding force of connector/connection angle ≥120 4.4.7
Flocking wear resistance ≥ Level-4 4.4.8
Low-temperature property of coating [(-
40±2) °C/24h]
Coating has no cracks, not
separated from the substrate 4.4.9
Light aging resistance ≤ Level-1 4.4.10
Hardness change (Shore A),
degree
Brittle temperature, °C
Items
Property indexes
Dense rubber Sponge rubber
Test
methods
Hardness change (Shore A), degree
Elongation at break, %
Tensile strength, MPa
Change rate of tensile
strength, %
Change rate of elongation at
break, %
Hardness change (Shore A),
degree
Change rate of tensile
strength, %
Change rate of elongation at
break, %
Hot air aging
Water resistance
Appearance density, g/cm3
Compression set, %
No higher than
Tensile 20%, (40±2) °C, 72h
Ozone concentration (2±0.2)10-6 Ozone aging resistance
No cracks No cracks No cracks No cracks No cracks No cracks
Pollution Method A Slightly polluted
Corrosivity Level-1: has not become black
NOTE 1: The windshield and flocked weatherstrips need to be tested for water resistance.
NOTE 2: The dumbbell-shaped test piece in the items of tensile strength and elongation at break is preferred to use the Type-2 test piece.
Weather aging resistance As per requirements of drawings 4.4.11
4 Test Methods
4.1 Appearance
The appearance quality shall be inspected by the visual examination method under
the standard environment conditions.
4.2 Specification size
4.2.1 For the inspection for the shape and size of the cross-section, take the sample
with thickness of (2~5) mm; then project on a 10× projection magnifier; perform control
inspection on the corresponding product cross-section by 10× magnification control
chart.
4.2.2 The length of the finished product shall be inspected by a special inspection tool
of the corresponding product, or measuring tool with corresponding accuracy.
4.3 Rubber properties
4.3.1 The hardness test shall be performed as per the method specified in GB/T 531-
1999.
4.3.2 The tests on tensile strength and elongation at break shall be performed as per
the method specified in GB/T 528-1998. Thereof, when calculating the area of the
sponge rubber test piece, the honeycomb shape shall be neglected. When measuring
the thickness and width of the test piece, the specimen shall be unstressed.
4.3.3 The hot air aging test shall be performed as per the method specified in GB/T
3512-2001. After the specimen is placed as per requirements, adjust for 2h at the
ambient temperature of (23±2) °C; then perform the corresponding property test.
4.3.4 Water resistance test: place the specimen in the deionized water at the specified
temperature; place it as required by the test time. When the test temperature is higher
than the lab standard ambient temperature for [(23±2) °C], fully immerse the specimen
in the constant temperature water batch; place it as required by the test time. After the
end of the placement, take out the specimen from the deionized water; firstly, dry it
with a clean fabric or paper with good water absorption properties; then adjust for 2h
at the ambient temperature of (23±2) °C; finally, perform the corresponding test.
4.3.5 The apparent density test of the sponge shall be performed as per the method
specified in HG/T 3055-1988 (1997).
4.3.6 The compression set test shall be performed as per the method specified in GB/T
7759-1996.
4.3.7 Brittle temperature test shall be performed as per the method specified in GB/T
1682-1994.
4.3.8 Ozone aging resistance test shall be performed as per the Method A in GB/T
7762-2003.
4.3.9 Pollution test shall be performed as per the method specified in GB/T 19243-
2003.
4.3.10 Corrosivity test shall be performed as per the method specified in Appendix A.
4.4 Properties of finished products
4.4.1 The specimen for the test on properties of finished products shall be taken from
the squeezing semi-finished products or finished products. The specimen shall meet
the following requirements:
a) The time interval between test and vulcanization (referring to the lower extrusion
line) and the adjustment of the specimen before test shall be carried out as per
the method specified in GB/T 2941-1991.
b) Before the test, the specimen shall be adjusted for 3h under the environment with
temperature of (23±2) °C, and relative humidity of (50±5) %; the specimen shall
not be applied force during the adjusting period.
c) Except for special requirements, three specimens shall be taken from different
finished products with the required length of the test.
4.4.2 Compression set test shall be performed as per the provisions of QC/T 709-2004.
4.4.3 Compression load test shall be performed as per the provisions of QC/T 710-
2014.
4.4.4 The tests on insertion force and withdrawal force shall be performed as per the
provisions of QC/T 716-2004.
4.4.5 Low-temperature property test shall be performed as per the provisions of
Appendix B.
4.4.6 Breakout force test between dense rubber and sponge rubber shall be performed
as per the provisions of Appendix C.
4.4.7 Binding force test between connector and connection angle shall be performed
as per the provisions of Appendix D.
4.4.8 Flocking wear resistance test shall be performed as per the provisions of QC/T
711-2004. Thereof, the hot air aging test shall be performed as per the requirements
in 4.3.3.
4.4.9 Low-temperature property test of coating shall be performed as per the provisions
of Appendix B.
4.4.10 Light aging resistance test shall be performed as per the method specified in
GB/T 12831-1991. The test conditions can refer to Table 4.
Table 4 – Light Aging Resistance Test Conditions
4.4.11 Weather aging resistance test shall be performed as per the method specified
in GB/T 3511-2001.
5 Inspection Rules
5.1 Inspection classification and items
The weatherstrip inspection can be divided into exit-factory inspection and type
inspection; the inspection items can refer to Table 5.
5.2 Batching rules
The batch of weatherstrips is manufactured by the same production line, the same raw
materials, the same process, with the same specification. The manufacturer can also
take the products within certain production cycle as one batch. He products shall be
inspected and accepted in batches.
Dry state
Categories Irradiation intensity Blackboard standard temperature
Relative
humidity Irradiation dose
Interiors
Exteriors
Wet state
Dry state: wet state= 102min:18min
Table 5 – Inspection Items and Types
5.3 Sampling plan and judgement rules
5.3.1 Exist-factory inspection
5.3.1.1 Inspection of appearance quality and finished product length: perform a normal
inspection as per GB/T 2828.1-2003 before the products leave the factory; the
sampling plan shall be inspected by random sampling with an AQL of 1.5 and general
test Level-II. If the products are judged to be unqualified, such batch of products shall
be returned to the production department for inspection one by one. After rework, the
products shall be inspected once in strict accordance with GB/T 2828.1-2003. The
sampling plan shall be re-inspected by random sampling with AQL of 1.5 and test
Level-II. Only when the reinspection is qualified, can the products leave the factory.
Breakout force between dense
rubber and sponge rubber
SN Inspection items Required clause
No. Test method clause No. Exit-factory Inspection Type Inspection
Appearance quality
Shape and size of cross-section
Length of finished product
Ru
bb
er
pro
pe
rtie
Fin
ish
ed
pr
od
uc
t p
rop
ert
ies
Hardness
Tensile strength
Elongation at break
Hot air aging
Water resistance
Apparent density
Compression set
Brittle temperature
Ozone aging resistance
Pollution
Corrosivity
Compression set
Compression load
Insertion force
Withdrawal force
Low-temperature properties
Binding force between
connector and connection angel
Flocking wear resistance
Low-temperature properties of
coating
Light aging resistance
5.3.1.2 Inspection of shape and size of cross-section, compression load, insertion
force, and withdrawal force: during the squeezing period, the number of random
sampling per shift per item shall be no less than 3 times. If the inspection is unqualified,
immediately adjust the parameters till the random sampling is qualified. The unqualified
products shall not be flow into the next process.
5.3.2 Type inspection
5.3.2.1 In case one of the following situations, the type inspection shall be performed:
a) The trial-production and finalizing identification of new products;
b) After the normal production, if there are major changes in design, structure,
material and process, and the product properties may be influenced;
c) When production is resumed after a long-time shutdown;
d) When the exit-factory inspection results significantly differ from the previous type
inspection;
e) When the state quality supervision authority propose the requirements for type
inspection.
5.3.2.2 Inspection of appearance quality, shape and size of cross-section, and finished
product length: randomly selected 2 pieces of products from the qualified products in
the exist-factory inspection. If one item fails after the inspection, then the type
inspection is unqualified.
5.3.2.3 Inspection of rubber properties: randomly select 3kg of rubber test sample.
After the test, if there is unqualified item, double samples shall be taken from the same
batch of rubber to carry out the re-inspection on the unqualified item. If the item is still
unqualified after the re-inspection, then this type inspection is unqualified.
5.3.2.4 Inspection of finished product properties: randomly select one piece each time
for each item. After the test, if there is unqualified item, double samples shall be taken
to carry out the re-inspection on the unqualified item. If the item is still unqualified after
the re-inspection, then this type inspection is unqualified.
6 Marking, Package, Transportation and Storage
6.1 Marking
6.1.1 The contents on the finished products shall be marked as per the requirements
of the user.
6.1.2 The product certificate can be marked as follows:
a) Product name or code;
b) Manufacturer name or number;
c) Production date or product batch number;
d) The number of pieces;
e) Inspector number and inspection mark for qualification;
f) This Standard number.
6.1.3 The contents on the packaging box shall be marked as per the requirements of
the user. If the user does not have specific requirements, please indicate as follows:
a) Product name or code;
b) Manufacturer name or number;
c) Production date or product batch number;
d) The number of pieces;
e) Stacking limit (corrugated box);
f) Packaging box size.
6.2 Package
6.2.1 The products shall be packaged as per the requirements of the user.
6.2.2 The products placed in the box shall be flat; and shall not be flattened or
deformed.
6.3 Transportation
The product transportation shall meet the requirements of 4.1 and 4.2 in GB/T 5721-
1993. If there are special requirements, it shall be determined through the negotiation
between the supplier and the purchaser.
6.4 Storage
6.4.1 The product storage shall meet the requirements of Clause 5 in GB/T 5721-1993.
6.4.2 Under abiding by the provisions of 6.2, 6.3 and 6.4.1, the product has a shelf life
of 2 years.
Appendix A
(Normative)
Corrosivity Test Method of Rubber Weatherstrips
A.1 Apparatus
A.1.1 Oven
The oven shall meet the relevant requirements of GB/T 9868-1988. The heat
transferring medium is air. The temperature is automatically controlled.
A.1.2 Test device
The corrosivity test device consists of load block, electrolytic copper plate and glass
plate. It is recommended to use the specification size specified in Table A.1.
Table A.1 -- Test Tooling and Sample Specification Size
A.2 Specimen
A.2.1 The specimen shall meet the relevant requirements of GB/T 2941-1991.
A.2.2 The specimen size is recommended to use the specification in Table A.1. If
necessary, when it is required to take sample from the finished products or the
specimen size differs greatly from the specification in Table A.1, the specimen can be
trimmed properly; meanwhile adjust the specification of the load block; so that the
pressure applied to the specimen is no less than 2.2×10-2N/mm2.
A.3 Test procedures
A.3.1 Use the metallographic sandpaper to rub the electrolytic copper plate; remove
the oxide layer on the surface; and use ethanol to clean the surface.
A.3.2 Place the specimen and load block as shown in Figure A.1. The total load on the
Name
Total load is the sum of load block and load of glass
plate
Specification Remarks
Total load
Electrolytic copper
plate
Glass plate
Specimen
2 blocks of Glass plate
specimen is the sum of load block and the load of a glass plate; so that the pressure
applied on the specimen is no less than 2.2×10-2N/mm2.
Figure A.1 – Corrosivity Test Specimen Assembly Schematic Diagram
A.3.3 Place the above specimen assembly into the oven conforming to the provisions
of GB/T 3512-2001. Test temperature is (100±2) °C, the standing time is 24h. After the
completion of the placement, take out the specimen assembly; remove the load and
specimen; adjust the electrolytic copper plate for 30min at (23±2) °C; then observe the
surface of the electrolytic copper plate and assess.
A.4 Expression of test results
According to the phenomenon observed from the surface of the electrolytic copper
plate, the test results shall be expressed as per the assessment level specified in Table
A.2.
Table A.2 – Assessment Level
Level Description
Level-1 Fails to become black
Level-2 Mild tempering color
Level-3 Severe tempering color
Level-4 Become black
A.5 Test report
The test report shall contain the following contents:
a) Test name and number;
b) This Standard number;
c) Sample name and source;
d) Specimen specification size;
e) Test condition: test temperature, test time, etc.;
Specimen
Glass plate
Load block
Electrolytic copper plate
f) Specification of electrolytic plate, glass plate and load block;
g) Indicating value;
h) Test results and any abnormal phenomenon observed during the test period;
i) Test personnel and date.
Appendix B
(Normative)
Low-Temperature Property Test Method of Rubber Weatherstrips
B.1 Apparatus
B.1.1 Low-temperature control box
The low-temperature control box shall meet the relevant requirements of GB/T 9868-
1988. It is recommended to use a low-temperature control box with a mechanical
refrigeration device.
B.1.2 Mandrel
The mandrel material shall be made of inert materials such as glass or ceramic, etc.
The mandrel diameter shall be selected according to the product requirements. It is
recommended to use a mandrel with a diameter of 50mm, 100mm.
B.2 Specimen
B.2.1 The specimen shall meet the requirements of 4.4.1.
B.2.2 The specimen shall be taken from the extruded semi-finished products or
finished products.
B.2.3 The specimen length shall be determined by satisfying that the specimen can
surround the mandrel and meet the operational requirements.
B.3 Test procedures
B.3.1 Place the specimen and mandrel in the test box at the specified temperature for
a certain time. Except for special provisions, the test temperature is -40°C; the
specimen placement time is 24h. For the low-temperature property test of coating of
the test weatherstrips, the specimen placement time is 4h. The specimen shall be in a
free state during the standing time, and shall not be subjected to any stress.
B.3.2 After the completion of the placement, use a gloved hand to take out the
specimen and mandrel; immediately surround and bend the specimen around the
mandrel for 180°. Use the visual examination to observe the surface of the weatherstrip;
record the observed results.
B.4 Test report
The test report shall contain the following contents:
a) Test name and number;
b) This Standard number;
c) Specimen name and source;
d) Specimen specification size;
e) Test conditions: test temperature, time, mandrel diameter and other relevant
parameters, etc.;
f) Index value;
g) Test results and any abnormal phenomenon during the test period;
h) Test personnel and date.
Appendix C
(Normative)
Test Method for Breakout Force between Dense Rubber and
Sponge Rubber of Rubber Weatherstrips
C.1 Apparatus
C.1.1 Tensile tester
The tensile tester shall meet the relevant requirements of HG/T 2369-1988; its force-
measuring accuracy shall be Level-A.
C.1.2 Test device
The test device consists of a set of upper and lower clamps. Its structure shall be
designed according to the product structure. The clamp shall be able to securely hold
the specimen during the test. The diameter of the drawbar shall be selected according
to the product drawings. The common structure can refer to Figure C.1.
(a)
(b)
Figure C.1 – Schematic Diagram of Structure of the Breakout Force Test Device
between Dense Rubber and Sponge Rubber
C.2 Specimen
C.2.1 The specimen shall meet the requirements of 4.4.1.
C.2.2 The specimen shall be taken from the extruded semi-finished or finished
products. Except for the special provisions, the specimen length shall be (100±2) mm.
C.3 Test procedures
C.3.1 According to the product test requirements, select the test working mode, set the
tensile speed, etc. Except for special provisions, set the speed to be 100 mm/min.
C.3.2 Install the clamp on the tensile tester. During the installation, make the load
action line applied by the clamp match the centreline of the specimen.
C.3.3 Install the specimen on the clamp of the tester; adjust the specimen; so that the
tensile force is evenly distributed on the specimen during the test.
C.3.4 Start the tester; make the clamp stretch at a constant speed by a specified tensile
speed till the specimen breaks; record the maximum force value. Take out the
specimen; check and record the broken surface situation of the specimen.
C.4 Expression of test results
Take the minimum value of all test data as the test result; it shall be rounded off to one
figure after the decimal point according to ......
......
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