How much pressure is generally used for air compressors in the chemical fiber industry

Technical description of air compressor pressure standard in chemical fiber industry

as an important application field of compressed air system, the process characteristics of chemical fiber industry determine the special requirements of air compressor pressure setting. Combined with the industry production practice, the chemical fiber enterprise air compressor pressure standards and management specifications are as follows:

1. industry pressure demand characteristics
chemical fiber production involves spinning, drafting, winding and other core processes, each process of compressed air pressure requirements show differentiated characteristics:

1. spinning process: 0.6-0.8MPa(6-8Bar) is required to stabilize the air pressure to ensure uniform melt ejection, and the pressure fluctuation should be controlled within ± 0.02MPa.
2. Drafting process: 0.4-0.6MPa(4-6Bar) grading pressure regulation to meet the stretching needs of different fiber varieties
3. winding process: 0.3-0.5MPa(3-5Bar) clean gas source required, equipped with 0.01μm grade terminal filter device
4. utilities: 0.5-0.7MPa(5-7Bar) base pressure is adopted for pneumatic conveying, instrument control and other auxiliary systems.

2. pressure setting principle

1. process matching mechanism
   establish a pressure database according to fiber varieties:

• polyester filament: main process pressure 0.7MPa, standby pressure 0.6MPa
• nylon staple fiber: drafting pressure segmented control (0.4/0.5/0.6MPa three-stage adjustment)
• spandex production: the reaction kettle sealing pressure needs to reach 1.0MPa, equipped with independent gas supply circuit

2. energy efficiency optimization scheme
   implementation of pressure step utilization:

• base load area: 0.6MPa gas supply to meet conventional demand
• boost regulation area: through the local booster pump to achieve pressure increase, compared with the whole system to raise pressure energy saving 25%
• recycling system: the winding process 0.3MPa residual pressure recovery to the spinning front, the overall energy efficiency increased by 8%

3. Key Equipment Configuration

1. dedicated air supply module

• spinning special unit: equipped with two-stage compression host, pressure stability of ± 0.01MPa
• clean air compression station: oil-free lubrication technology is adopted, and the oil content of compressed air is ≤ 0.003 mg/m & sup3;
• frequency conversion control system: automatically adjust the air supply pressure according to the speed of the production line, the response time is ≤ 0.3 seconds

2. auxiliary device requirements

• air storage tank group: the total volume shall not be less than 30% of the exhaust volume of the unit, equipped with automatic drainage device
• filter system: three-stage filter device (5 μm/1 μm/0.01 μm), replace the filter element every 2000 hours
• drying device: adsorption dryer, to achieve -40 ℃ pressure dew point, supporting dew point monitor

4. operation and maintenance management specification

1. daily inspection system

• record the pressure of the main pipe network every hour and draw the pressure fluctuation curve
• daily check the working status of the special pressure regulating valve for spinning and clean the filter element
• check the accuracy of the pressure gauge every week, and replace it immediately if the error exceeds 1.5%.

2. Regular inspection items

• the pipe network pressure holding test shall be carried out every quarter, and the pressure attenuation rate shall be ≤ 0.03MPa/hour.
• Entrust a third-party testing agency to conduct a full-system stress test every year and issue a calibration certificate.
• Pressure test shall be carried out on the gas storage tank every three years, and the test pressure shall be 1.25 times of the design pressure.

3. Emergency Treatment Plan

• abnormal pressure rise: when the safety valve is not started, close the intake valve manually immediately
• sudden pressure drop fault: start the standby unit and check the leakage of the pipe network.
• Sensor failure: switch to the standby monitoring channel and complete the replacement of faulty parts within 2 hours.

Enterprises should establish a pressure management system for chemical fiber special air compressors, and formulate exclusive pressure management standards in combination with the requirements of GB 50029 "Code for Design of Compressed Air Stations. It is recommended to conduct a system pressure assessment every six months, focusing on key indicators such as pressure stability (≤ ± 0.02MPa), equipment response speed (≤ 0.3 seconds), and safety device reliability (100%), so as to continuously optimize the system operation quality and ensure the stability of fiber product quality.