Before reading this article, please click on the blue font " China Chemical Safety Association " under the heading of this article and then click on " Follow ", so that you can receive the article for free. Share every day, it's a free subscription, please rest assured!
Pressure test of a device and piping system
(1) Pipeline system pressure test conditions
1. The safety valve has been blinded and the blasting plate has been removed and blinded.
2 , the expansion joint has been added to the restraint device.
3. The spring branch and hanger are locked.
4. When the test is carried out with water as the medium, the bearing capacity of the structure has been confirmed or accounted for.
5. The pressure gauge has been verified.
(2) The following provisions shall be observed
1. Pressure testing with air and process media must be approved by the production and safety departments.
2. Confirm that the test system has been effectively isolated from the unrelated system before the test.
3. When conducting water pressure experiments, clean fresh water is used as the test medium. When the system is connected with austenitic stainless steel equipment or pipes, the chloride ion content in the water shall not exceed 0.0025%.
4. The test temperature must be higher than the brittle transition temperature of the material.
5 , when testing in the cold season, there must be anti-freezing measures.
6. The hydraulic test pressure of the steel pipeline is 1.5 times of the design pressure; when the design temperature is higher than the test temperature, the test pressure shall be converted according to the ratio of the allowable stress at the two temperatures, but shall not exceed the yield strength of the material. When tested with a gas, the test pressure is 1.15 times the design pressure.
7. When the test pressure of the equipment in the test system is lower than the test pressure of the pipeline and the test pressure of the equipment is not less than 115% of the pipeline design pressure, the pipeline system can be tested according to the test pressure of the equipment.
8. When the test system is connected to a device that can only withstand the pressure difference, it must be ensured that the pressure difference does not exceed the specified value during the ascending and depressurizing processes.
9. When testing, it should be slowly boosted. When testing with liquid, it should be conditioned for 10 minutes at the test pressure and then lowered to the design pressure to check for leaks. When testing with gas, the test should first be carried out at a pressure lower than 0.17Mpa (gauge pressure), then boosted to 50% of the design pressure, then gradually increased to the test pressure and stabilized for 10 minutes, then reduced Design pressure to check for leaks.
10. After the test is over, drain water and gas and do a good job of resetting.
Two equipment, pipeline system leakage test
(1) Leakage tests must be carried out when transporting toxic media, flammable media, and other media that must be tested for leaks as specified in the design.
(2) Leakage test should be carried out after pipe cleaning or purging.
(3) When the air pressure test is carried out, it can be combined with the leak test. However, after the pipe cleaning or purging is qualified, the final leak test is required. The inspection focus is on the pipe reset.
(4) The following provisions shall be observed
1. The test pressure is not higher than the design pressure.
2. The test medium is generally air.
3. The vacuum system leakage test pressure is 0.01 MPa (absolute pressure).
4. Check the method specified in the design file.
Three water rinse
(1) The pressure test is qualified. The machinery, instruments, valves, etc. in the system have taken protective measures. The temporary pipeline is installed, the flushing pump can be operated normally, and the water filter can be washed after the filter is installed at the inlet of the flushing pump.
(2) If the rinsing work is carried out during the severe cold season, anti-freeze and anti-skid measures must be taken.
(3) When filling and draining, the piping system should be connected to the atmosphere.
(4) Before the pipeline and mechanical washing of the previous process are qualified, the flushing water shall not enter the machinery of the next process.
(5) Flushing water should be discharged into the designated place.
(6) After flushing, ensure that all drainage and exhaust pipes are unblocked.
Four steam purge
(1) Steam purge conditions
1. The pipeline system pressure test is qualified.
2. According to the design requirements, reserve the location of the pipeline interface and the short section, and install the temporary pipeline; the pipeline safety standard should meet the requirements of relevant regulations.
3. Effective protection measures have been taken for valves, instruments and machinery.
4. Confirm that there are no combustibles on and near the pipeline system, and effectively isolate the pipelines adjacent to the transport of combustible materials to ensure that fires do not cause fire when the combustibles leak.
5. The steam supply system can be operated normally, and the steam volume can ensure the need for purging and use.
6. A fence has been installed around the restricted area and has a striking sign.
7. The tester has been protected according to the regulations and has worn anti-shock earmuffs.
(2) The following provisions shall be observed
1. Steam piping is strictly prohibited for piping systems that do not consider expansion.
2 , before the steam purge, first warm the tube, open all the guide tube, drain the condensate to prevent water hammer.
3. Blow the guide tube one by one when purging.
4. Strictly check the reset work, confirm that the pipeline system has been fully restored, and the pipeline and mechanical joints must be freely aligned according to the specified standards.
5 , the purge should have noise reduction measures.
Five chemical cleaning
(1) There are no debris and oil stains inside the pipeline system.
(2) The chemical cleaning liquid is analyzed by the quality inspection department to meet the standard requirements, and it can be confirmed that it can be used in the system to be washed.
(3) It has a chemical cleaning flow chart and a blind plate position map.
(4) The facilities, heat sources, medicines, analytical instruments and tools required for chemical cleaning have been prepared.
(5) Chemical cleaning personnel have been dressed in accordance with the protective regulations and wear protective equipment.
(6) If the pipeline system after chemical cleaning is temporarily unavailable, it should be protected with inert gas.
(7) Sewage must be treated to meet environmental requirements before it can be discharged.
Six air purge
(1) Pipes with a diameter greater than 600 mm should be cleaned manually.
(2) The system pressure test is qualified, and effective protection measures have been taken for the machinery, instruments and valves in the system.
(3) The position of the blind plate has been confirmed, and the gas source is guaranteed; when the oil pipeline is purged, the air must not contain oil.
(4) The resetting work after purging should be strictly checked.
(5) Purging should have measures such as covering, warning, preventing staying, and preventing noise.
Seven- cycle water system pre-film
(1) Pre-film conditions of circulating water system
1. The system is qualified for water washing.
2 , the circulating water system linkage test is qualified.
3 , the liquid has been tested and proved to be suitable for on-site water quality, the film formation effect is good, and the corrosion is lower than the design regulations.
4. The test piece for observing the pre-film condition has been set in the system as specified.
5. Effective measures have been taken to dispose of waste liquid.
(2) The following provisions shall be observed
1. The pre-filming work should avoid the cold season, if it is not necessary to have anti-freezing measures.
2. The pre-filming work of the system should be completed once, and no pre-filmed pipes and equipment should be left in the system.
3. After pre-filming, it should be administered according to the amount on time, so that the system is in the film-protecting state.
Eight system replacement
(1) Before the pilot system is introduced with flammable gas, the air must be replaced with an inert gas, and the inert gas must be replaced by a flammable gas. Before the vehicle is overhauled, the flammable gas in the system must be replaced with an inert gas, and the inert gas should be replaced by air. Pay attention to the toxic and harmful solid and liquid replacement treatment.
(2) System replacement conditions
1. Replacement flow chart indicating the clearance point, analysis point and blind position.
2. The sampling and analysis personnel are in place, and the analytical instruments and medicines are ready.
3 , inert gas can meet the needs of replacement work.
(3) The following provisions shall be observed
1. The oxygen content in the inert gas shall not exceed the safety standard.
2. Confirm the quantity, quality and installation location of the blind plate.
3. When replacing, pay attention to the dead angle in the system. If necessary, you can use repeated pressure boosting and pressure relief to dilute the replacement gas.
4. When the pipeline system is connected to the gas cabinet, the gas cabinet should be repeatedly raised and lowered three times to replace the gas in the annular water seal.
5 , the replacement work should be carried out in the order of the first supervisor and the rear branch.
6. When analyzing the sample, the analyst should pay attention to the wind direction and the height and direction of the venting pipe to prevent poisoning.
7. The analysis data shall be subject to three consecutive passes and shall be signed and confirmed by the responsible persons of production, technology and safety.
8. After the replacement is completed, the inert gas pipeline and the system are effectively isolated.
(4) Eligibility criteria
1. When the flammable gas is replaced by inert gas, the flammable gas component in the gas after replacement shall not exceed 0.5%.
2. When the inert gas is replaced by a flammable gas, the oxygen content in the replaced gas shall not exceed 0.5%.
3. When the air is replaced by inert gas, the oxygen content in the replaced gas shall not be higher than 1%. If the flammable or explosive medium is directly input after replacement, the oxygen content in the replaced gas shall not be higher than 0.5%.
4. When the air is replaced by air, the oxygen content in the replaced gas shall not be less than 20%.
Nine general electric machine test
(1) General electric machine test conditions
1. Pipes and equipment related to machine test have been purged or cleaned.
2. The filter (device) is set at the entrance of the machine.
3. The pressure lubrication sealing oil pipeline and equipment are qualified by oil washing and have been tested.
4. The protective interlocking, early warning, indication and automatic control devices of the motor and machine have been debugged.
5 , safety valve commissioning qualified
6. The direction of motor rotation has been checked and the motor grounding is qualified.
7. The equipment cover has been installed.
(2) The following provisions shall be observed
1. The test medium should be in accordance with the design documents. If there is no special regulation, the pump and the agitator should use water as the medium, and the compressor and fan should use air or nitrogen as the medium.
2 , the cryopump should not use water as the test medium, otherwise the water must be drained after the test, thoroughly blown dry, dried and checked to confirm the pass.
3. When the proportion of the test medium is greater than the specific gravity of the design medium, pay attention to the current of the motor during the test, and do not exceed the specified.
4 , must drive before the test drive.
5. After the motor has passed the test, the machine can be tested.
6 , the machine should generally carry out no-load test, and then load test.
7. When testing the car, pay attention to check the temperature of the bearing (tile) and packing, the vibration of the machine, the current, the outlet pressure and the filter.
8. Instrument indication, alarm, automatic control and chain should be accurate and reliable.
Filling of ten towers and internal parts
(1) Tower and internal parts filling conditions
1. The tower and the system are qualified for pressure test.
2 , the tower, the device and other internal clean, no debris, the concentration of toxic and combustible materials inside the equipment after anti-corrosion treatment meets relevant standards.
3 , with a lining tower, the device, the lining inspection qualified.
4. The manhole and the venting tube are all open, and the tower and the device are well ventilated.
5. The packing has been cleaned.
6. Filling equipment is available.
7. Have entered the restricted space operation permit.
(2) The following provisions shall be observed
1. Personnel entering the tower shall not carry items that are not related to the filling work.
2. Personnel entering the tower shall wear and wear protective equipment as required, and assign special personnel to supervise.
3. Unqualified internals and fillers mixed with debris shall not be installed.
4. When installing the tray, the installer should stand on the beam.
5 , the distribution of distributors, trays and their accessories and the arrangement of fillers should be strictly carried out in accordance with the provisions of the design documents, reviewed and recorded by professional and technical personnel.
6. Before the tower and the device are closed, all the tools and unnecessary items that are carried with them should be cleaned up. After the closure, the leak test should be carried out.
Filling of eleven catalysts, molecular sieves, etc.
(1) Filling conditions such as catalysts and molecular sieves
1. The variety, specifications and quantity of the catalyst meet the design requirements and the storage status is good.
2 , the reactor and related system pressure test passed.
3. The reactor with heat-resistant lining is qualified by the oven.
4. The inside of the reactor is clean and dry.
5 , filling equipment and various facilities are available.
6 , has entered the restricted space operation permit.
(2) The following provisions shall be observed
1. Personnel entering the reactor must not carry items that are not related to the filling work.
2. When filling the catalyst, special personnel supervision must be specified.
3. Fillers must wear and wear protective masks as required.
4. Unqualified catalysts (crushing, crushing, etc.) must not be loaded into the unit.
5. When filling, the free fall of the catalyst should not exceed 0.5 meters.
6. Fillers should not stand directly on the catalyst.
7. Filling work should be carried out in strict accordance with the provisions of the filling plan.
8. Check the pressure drop in parallel reactors to ensure uniform airflow distribution.
9. The pre-reduction catalyst is protected with an inert gas after filling, and a person is assigned to monitor the temperature change of the catalyst.
10. Leak test should be carried out after the reactor is reset.
Re-inspection of twelve heat exchangers
(1) The leak test shall be carried out again after the heat exchanger is delivered to the site. When there is a stipulation, the core check shall be carried out.
(2) Test water or chemicals should meet the test needs.
(3) During the test, water injection, pressure charging, and key inspection of the rising mouth or welding joint shall be carried out, and the control shall be within the normal range.
(4) If a leak is found in the pipe, a core inspection shall be carried out.
(5) If it is required to carry out inspection with ammonia or other medium as required, it shall be carried out according to special regulations.
(6) After inspection, water should be drained and blown dry with air.
Thirteen instrument system debugging
(1) Pre-commissioning conditions of the instrument system
1. The instrument air station has normal operating conditions and the instrument air duct system has been purged.
2. The air conditioning and uninterruptible power supply in the control room can be used normally.
3 , transmitter, indicator recording instrument, chain and alarm switch, regulating valve and panel, rack mounted instrument, etc. have been adjusted.
4. The relevant parameters of the automatic control system regulator have been preset. The feedforward control parameters, ratio values ​​and various corrected ratio bias systems have been calculated and preset according to the relevant data.
5 , all kinds of analog signal generating devices, test instruments, standard sample gas, communication tools, etc. are available.
6. All field instruments and regulating valves are in the commissioning state.
7. For the key equipment and key positions involved (one major and two key points), the automatic chain and alarm system should be separately debugged to ensure the integrity.
(2) The following provisions shall be observed
1. The detection and automatic control system should be simulated before the joint test with the machine, that is, input the analog signal at the transmitter, check and adjust the input processing control manual and automatic switching and output on the console or secondary instrument. All the functions of the process.
2 , chain and alarm system should be simulated before the mechanical joint test, that is, input analog signal at the switch, check its logic and action, and adjust to pass.
3. When adjusting the instrument with the mechanical test, the instrument, electrical and process operators must cooperate closely with each other.
4. The interlocking device that is temporarily unable to be used for the first test or under load may be temporarily removed with the consent of the construction (production) unit, but the alarm device shall be retained.
5. Before the chemical commissioning test, the feedforward control, ratio control and control system containing the corrector should be used to re-set the parameters according to the load amount and the actual material composition.
Fourteen electrical system debugging
(1) Pre-commissioning conditions of the electrical system
1. Isolation switch, load switch, high voltage circuit breaker, insulation material, transformer, transformer, silicon rectifier, etc. have been debugged.
2. The insulation resistance of the relay protection system and the secondary circuit has been tested and adjusted for withstand voltage.
3. Test report with high-voltage electrical insulating oil.
4 , with battery charge, discharge record curve and electrolyte test report.
5. Test record with lightning protection and protective grounding resistance.
6 , with a test record of the motor, cable test.
7. Have a record of chain protection test qualification.
(2) The following provisions shall be observed
1. The power supply and distribution personnel must be employed according to the system and strictly implement the operation system.
2. The transformer and the pre-phase system of the relay protection device, the automatic reclosing device, the alarm and the pre-phase system must be simulated according to the system before the power is changed.
3. The protection device of the programmable logic controller shall simulate the interlocking and alarm parameters item by item, and verify the correctness of the positive alarm value of the logic.
4. The test and confirmation of the accident power supply system should be carried out.
5. It should be operated in accordance with the prescribed power transmission and delivery procedures.
6. Electrical system acceptance should be carried out before power transmission.
The fifteen key equipment test should have the following conditions
(1) The system pipeline pressure test and the heat exchange equipment airtight test are qualified.
(2) The process and steam pipeline are qualified for purging or cleaning.
(3) The cleaning of the lubricating oil, sealing oil and control oil system of the equipment is qualified.
(4) The safety valve has been debugged and sealed.
(5) Qualified with the commissioning of the electrical, instrumentation, automatic chain control, alarm system, computer, etc. related to the test run.
(6) The power required for commissioning, instrument air, circulating water, desalinated water and other media are in place.
(7) The commissioning plan has been approved, and the command, operation and insurance personnel are in place. Test instruments, tools, protective equipment, and record forms are fully prepared.
(8) The test equipment and the system connected to it are completely isolated.
(9) The test area has been demarcated and the relevant personnel's voucher has entered.
(10) Determination of technical indicators for commissioning
(Source: Binzhou Safety Supervision Office)
Good things not only to collect, but also to forget to share friends
Metal sheet & tube Laser Cutting Machine available for metal plate and tube cutting in various materials such as stainless steel, carbon steel, alloy steel, spring steel, copper, aluminum, gold, sliver, titanium etc.
Metal sheet & tube laser Cutting Machine advantage:
1. Auto - focus
Applicable to various focal lengths, which are controlled by machine tool control system. Focal point will be automatically adjusted in cutting process to achieve the best cutting effect of different thicknesses sheets metal.
2. Free
Focal length is controlled by operating system. We don`t need to do manual regulation, which effectively avoids errors or faults caused by manual operation.
3. Fast
Auto focus would automatically adjust the most appropriate focal points in the process of punching and cutting, which greatly improves cutting speed;
4. Accuracy
Metal sheet & tube laser cutting machine with increasing perforation focus length, separately setting perforation focal length and cutting focal length, enhance cutting accuracy.
Metal Sheet & Tube Laser Cutting Machine
Laser Tube Cutting Machine,Metal Laser Cutting Machine,Metal Laser Cutter,Laser Cutter
Jinan Huaxia Machinery Equipment CO.,Ltd , https://www.cnformingmachine.com