MT/T 715-1997General specification of explosion-proof electromagnet valves in coal mine (English PDF)

4.1 Classification and naming.

4.2 Electromagnet valves shall comply with the requirements of this standard.

They shall be manufactured in accordance with the drawings and technical

documents approved by the prescribed procedures.

4.3 Appearance.

The surface of the electromagnet valve shall be coated or plated for anti-

corrosion. The coating and plating shall be uniform, and free from peeling off,

deformation, cracking, corrosion or damage.

4.4 Electromagnet valves shall be able to adapt to the following environmental

conditions.

4.5 The nominal diameter, water pressure's adaptation range and external

pipe's size of electromagnet valve shall meet the requirements of Table 1.

4.6 Rated voltage.

The rated voltage of the electromagnet valve shall meet the requirements of

Table 2.

4.7 Voltage variation's adaptation range.

The electromagnet valve shall work normally within the range of 80% ~ 120%

of the rated voltage.

4.11 The explosion-proof performance of the electromagnet valve shall comply

with the relevant provisions of GB 3836.1 and GB 3836.2.

4.12 The degree of protection of the electromagnet valve's casing is IP54.

4.13 Electromagnet valves shall, after alternated damp heat, working

temperature, storage temperature, vibration, shock and transport tests, comply

with the requirements of 4.7 and 4.10.

5.1 Test environment's temperature. 15 °C ~ 25 °C.

5.2 Test equipment and materials.

5.3 Appearance is checked by visual inspection.

5.4 The water pressure's adaptation range test for electromagnet valve.

5.6 Test of tightness.

Connect the electromagnet valve to the system as shown in Figure 1.Adjust

the power supply's voltage to be within the rated range. Let the electromagnet

valve be in closed state. Then input the 1.1 times the maximum working water

pressure from the inlet end, keep it for 1 min. Check whether the electromagnet

valve leaks.

5.8 Test of insulation resistance.

Use a 500 V megameter to measure the insulation resistance between the

electromagnet valve's terminal block and the metal casing.

5.9 Test of pressure resistance.

It is performed according to GB/T 998.

5.10 Test of explosion-proof performance.

It is performed according to the relevant methods of GB 3836.1 and GB 3836.2.

5.13.3 After the test, it is recovered in normal environment for 2 h, then tested

according to 5.3 and 5.8.

5.14 Test of storage temperature.

5.14.1 Low-temperature test.

It is performed according to the method Ab as specified in GB/T 2423.1;

Duration. 16 h;

Severity. -40 °C.

5.16 Shock test.

The shock test is carried out according to the method as specified in GB/T

2423.5;

5.17 Test of transport.

The packaged electromagnet valve is placed on a simulated automotive

transport test rig for a duration of 2 h.

6.1 Inspection items are as shown in Table 4.

6.3 Type test.

Type test shall be carried out in one of the following cases.

6.4 For the samples for type test, it shall take two sets in accordance with the

provisions of GB/T 10111 from the products that have passed the exit-factory

inspection.

6.5 Judgment rules.

At the time of exit-factory inspection, if one of the specified inspection items

fails, the set is judged to be unqualified.

7.1 Marking

7.1.1 Product's marking

7.1.2 Packaging marking

7.1.2.1 Packaging storage and transport markings shall comply with the

provisions of GB 191.

7.1.2.2 The transportation receipt and delivery marking shall comply with the

provisions of GB/T 6388.

7.2 Packaging

The packaging box shall contain the following documents.

7.3 Storage

Electromagnet valves shall be stored in a dry, well-ventilated environment to

prevent contact with corrosive materials.

MT/T 715-1997

MT

COAL INDUSTRY STANDARD OF

THE PEOPLE'S REPUBLIC OF CHINA

ICS 29.260.20

D 98

General specification of explosion-proof

electromagnet valves in coal mine

Issued on. DECEMBER 30, 1997

Implemented on. JULY 01, 1998

Issued by. Ministry of Coal Industry of People's Republic of China

Table of Contents

Foreword... 3

4.1 Classification and naming.

4.2 Electromagnet valves shall comply with the requirements of this standard.

They shall be manufactured in accordance with the drawings and technical

documents approved by the prescribed procedures.

4.3 Appearance.

The surface of the electromagnet valve shall be coated or plated for anti-

corrosion. The coating and plating shall be uniform, and free from peeling off,

deformation, cracking, corrosion or damage.

4.4 Electromagnet valves shall be able to adapt to the following environmental

conditions.

4.5 The nominal diameter, water pressure's adaptation range and external

pipe's size of electromagnet valve shall meet the requirements of Table 1.

4.6 Rated voltage.

The rated voltage of the electromagnet valve shall meet the requirements of

Table 2.

4.7 Voltage variation's adaptation range.

The electromagnet valve shall work normally within the range of 80% ~ 120%

of the rated voltage.

4.11 The explosion-proof performance of the electromagnet valve shall comply

with the relevant provisions of GB 3836.1 and GB 3836.2.

4.12 The degree of protection of the electromagnet valve's casing is IP54.

4.13 Electromagnet valves shall, after alternated damp heat, working

temperature, storage temperature, vibration, shock and transport tests, comply

with the requirements of 4.7 and 4.10.

5.1 Test environment's temperature. 15 °C ~ 25 °C.

5.2 Test equipment and materials.

5.3 Appearance is checked by visual inspection.

5.4 The water pressure's adaptation range test for electromagnet valve.

5.6 Test of tightness.

Connect the electromagnet valve to the system as shown in Figure 1.Adjust

the power supply's voltage to be within the rated range. Let the electromagnet

valve be in closed state. Then input the 1.1 times the maximum working water

pressure from the inlet end, keep it for 1 min. Check whether the electromagnet

valve leaks.

5.8 Test of insulation resistance.

Use a 500 V megameter to measure the insulation resistance between the

electromagnet valve's terminal block and the metal casing.

5.9 Test of pressure resistance.

It is performed according to GB/T 998.

5.10 Test of explosion-proof performance.

It is performed according to the relevant methods of GB 3836.1 and GB 3836.2.

5.13.3 After the test, it is recovered in normal environment for 2 h, then tested

according to 5.3 and 5.8.

5.14 Test of storage temperature.

5.14.1 Low-temperature test.

It is performed according to the method Ab as specified in GB/T 2423.1;

Duration. 16 h;

Severity. -40 °C.

5.16 Shock test.

The shock test is carried out according to the method as specified in GB/T

2423.5;

5.17 Test of transport.

The packaged electromagnet valve is placed on a simulated automotive

transport test rig for a duration of 2 h.

6.1 Inspection items are as shown in Table 4.

6.3 Type test.

Type test shall be carried out in one of the following cases.

6.4 For the samples for type test, it shall take two sets in accordance with the

provisions of GB/T 10111 from the products that have passed the exit-factory

inspection.

6.5 Judgment rules.

At the time of exit-factory inspection, if one of the specified inspection items

fails, the set is judged to be unqualified.

7.1 Marking

7.1.1 Product's marking

7.1.2 Packaging marking

7.1.2.1 Packaging storage and transport markings shall comply with the

provisions of GB 191.

7.1.2.2 The transportation receipt and delivery marking shall comply with the

provisions of GB/T 6388.

7.2 Packaging

The packaging box shall contain the following documents.

7.3 Storage

Electromagnet valves shall be stored in a dry, well-ventilated environment to

prevent contact with corrosive materials.

......