Test Item

Test Method

Criteria

Measurement of Dimension

Inner Diameter

Two end points of inner side of hoses are to be measured at the right angle direction and make average.

The diameter is to be within allowable tolerance.

Outer Diameter

Outer side of hoses is to be measured at the right angle direction and make average.

Thickness

Measure the thinnest point.

Performance Test

Pressure Test

Pressure Test

One side of the specimen is free, Test medium : water or oil, Test pressure : a pressure 1.5 times of the design pressure, Test duration : 5 minutes.

During test period, no rupturing, leaking are permitted.

Burst Test

Test pressure : a pressure 4 times of the design pressure, Test duration

: 5 minutes

Leakage Test

One side of the specimen is free, Test medium : inert gas or air, Test pressure : a pressure same as the design pressure, Test duration : im- merse the specimen in water for 5 minutes.

Vacuum Test

One side of the specimen is free, Test pressure : absolute pressure 88 KPa, Test duration : 5 minutes.

Cold Test

This test is applied to the hose assembly which the design temperature is 0℃ and below. Remain the specimen in low temp. room at minimum

design temp. for 5 min. and bend both sides within 12 seconds as re- quired bending radius as Fig below and then examine the condition of the specimen. Remain the tested specimen at room temp. and it is to be subjected to pressure test at least 1.5 times of design pressure.

During test period, no rupturing, leaking are permitted.

Electric Test

Electric Conduction Test

Connect 4.5 V battery and 3.8 V, 0.3 A light on the specimen and ex- amine the electric conductivity in accordance with the result of lighting. In case where metal is attached on hose, carry out the test between metal of both ends and otherwise, between electric wires of both ends. where there are not the electric wires, carry out the test after connecting metals to both ends.

The light is to be turned on.

In su la t io n Resistance Test

The specimen is to be installed in accordance with Fig below and measure insulation resistance using 500 V insulation resistance tester af- ter connecting metals to both ends.

The measured in- sulation resistance shall not be more

than 1MΩ.

Adhesion Test

Adhesion test of each layer of hose is to be carried out in accordance with KS M 6787.

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Test Item

Test Method

Criteria

Ozone Resistance Test

This test is to be carried out in accordance with KS M 6790 using hose which is rolled on a cylinder and examine crack of outer rubber layer.

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Thermal Aging Test

After aging the specimen in accordance with KS M 6788 during re- quired time, leave it for 3 hours ~ 24 hours at room temp. Bend it un- til 180° within 5 seconds in accordance with Fig below and then exam- ine the condition of it. The test specimen is to be subjected to pressure test at least 1.5 times of design pressure.

*

During test period, no rupturing, leaking are permitted.

Impulse Test

Hose Without Flexing

The specimen where the nominal bore size up to 22 mm is to be bent through 180° and the nominal bore size above 22 mm is to be bent through 90°. Repeat maximum impulse pressure which is 133 % of de- sign pressure until 4× 105 or breakdown and record the number of cycle. The detailed test procedure is prescribed in KS M ISO 6803.

During test period, no rupturing, leaking are permitted. Leakage at the end fitting, blow-off or rupture of the hose within 25 mm of the fitting is to be considered as failures.

Hose With Flexing

After installing a revolving manifold and a horizontally reciprocating manifold, carry out the test in accordance with the test cycle of Fig The detailed test procedure is prescribed in KS M ISO 6802.

Mechanical Test of Vulcanized Rubber

Tensile Test

Tensile test is to be carried out in accordance with KS M 6782 and measure tensile strength and elongation.

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Hardness Test

Hardness test is to be carried out in accordance with spring type test method of KS M 6784.

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Aging Test

Aging Test (Air Heat)

Carry out this test in accordance with air heat aging test method of KS M 6788 and calculate the variation of tensile strength and elongation before and after this test. In this case, test temp. is one of among 70±

1℃, 100± 1℃ and 120± 1℃ and test time is one of among 48 hours,

72 hours and 96 hours.

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Aging Test (Steam Heat)

After air heat aging test, the same specimen is to be left in saturated vapour during the required time and then left for 24 hours. Carry out tensile test and calculate the variation of tensile strength and elongation.

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Dipping Test

Dipping test is to be carried out in accordance with KS M 6789 and calculate the variation of volume, tensile strength and elongation before and after this test and examine the condition of the surface.

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Minimum width of burner (mm)

Outside diameter of hose (mm)

50

up to 25

100

over 25 up to 75

150

over 75 up to 125

200

over 125 up to 150

250

over 150 up to 200

Test Item

Test Method

Criteria

Fire Resistance Test

Fire Resistance Test

① Hose length : Minimum 500 mm and above.

② Test medium : Water only.

③ Installation of test specimen : The test specimens are to be installed

on the test bench such that the burner end extends beyond a hose

sitting by at lease 20 mm such that the fitting is completely en- closed by the flames.

④ Width of burner : In order to ensure that the flames reliably enclose

the test specimen, the minimum burner widths shown in Table be-

low is to be observed.

Table Width of burner

⑤ Preparation : The test specimen is to be rinsed with the test medium water for at least 1 minute, in order to evacuate as far as possible the air contained in the test specimen.

⑥ Measured values and Measuring points: The following measured val-

ues is to be determined at the measuring points indicated in Fig

a) Water temp. at measuring points 1 and 2

b) Flame temp. at measuring points 3 and 4

c) Flow rate of water

d) Pressure inside test specimen during the flame application

⑦ Test temperature : The test duration starts at the moment the test specimen is exposed to the test temperature which is to have been reached at both measuring points in accordance with Table below.

⑧ Pressure : 5± 0.2 bar during flame application

⑨ Duration of test : 30 minutes, the duration starts at the moment the

test specimen is exposed to the test temp. which is to have been

reached at both measuring points.

⑩ Pressure test : Following the flame application, a pressure test is to

be carried out at a pressure twice of the design pressure for 2

minutes.

The test specimen remains tight during the proof pressure test after flame application.

Temp.

of water at temp. measuring point 1

80±2℃

Temp.

of water at temp. measuring point 2

max. 85℃

Temp. and 4

of flame at temp. measuring points during test

3

800±50℃