The scientific allocation of the compressed air system in the factory building is the key link to ensure production efficiency and reduce operating costs. The determination of gas volume requires comprehensive consideration of equipment requirements, usage characteristics and system losses, and the core basis and methods are described below from a professional perspective:
1. gas equipment demand accounting
- statistics of equipment gas consumption
the gas equipment of the whole plant shall be classified and counted, and the rated gas consumption of various equipment shall be specified. For example:- pneumatic tools: such as air cannon and spray gun, the gas consumption of a single unit is about 0. 2-0.6m³/min;
- automation equipment: For example, pneumatic manipulator and conveying device, the gas consumption of a single machine is about 0. 5-1.5m³/min;
- process Equipment: Such as spraying machine, bottle blowing machine, single gas consumption can reach 3- 8m³/min.
- Analysis of gas peak and valley
through PLC data acquisition or electric energy meter monitoring, the 24-hour gas consumption curve is drawn to identify the peak demand and valley demand, and provide data support for system selection.
2. dynamic use factor correction
- coefficient of simultaneous use (K value)
determine the simultaneous use coefficient according to the use characteristics of the equipment to avoid waste of resources caused by simple superposition of the rated gas volume of the equipment:- continuous production plant(such as chemical, food):K value 0.7-0.8;
- intermittent production plant(such as auto parts):K value is 0.6-0.7;
- multi-shift operation factory: The K value needs to be calculated in different periods, such as day shift 0.75 and night shift 0.65.
- Design of Buffer with Gas Fluctuation
when configuring the air storage tank, it is necessary to ensure that its volume is ≥ 10% of the total air demand. -15% in order to smooth the fluctuation of gas consumption and reduce the frequent start and stop of the air compressor.
3. system loss compensation
- pipeline pressure loss
the pressure loss will be caused by the pipeline length, pipe diameter, number of elbows and other factors, which shall be estimated according to the following formula:- pressure loss (ΔP)= 1.6 ×(L/D)× Q²
(L: pipe length, D: pipe diameter, Q: flow) - usually need to reserve 5%-15% of the gas compensation.
- pressure loss (ΔP)= 1.6 ×(L/D)× Q²
- Leakage control
the leakage rate of compressed air system is generally between 10% and 30%, which should be controlled by the following measures:- regularly carry out ultrasonic leak detection and repair leakage points above DN10;
- in the design, 10%-20% of the gas volume is reserved as leakage compensation.
4. Future Expansion Reservation
-
capacity expansion demand
according to the enterprise development plan, reserve 20%-30% of the gas margin to avoid system transformation due to capacity expansion. -
Process upgrade space
interfaces are reserved for automatic upgrading and new process equipment. Modular design is recommended to facilitate later expansion.
5. typical industry configuration case
| industry type | configuration Scenario | key parameters |
|---|---|---|
| automobile Manufacturing | 4 55kW frequency conversion screw machines + 60m ³ air storage tanks | simultaneous use of coefficient K = 0.75 |
| electronic Manufacturing | 3 37kW oil-free scroll machines + 40m ³ gas storage tanks | cleanliness ISO class 5, pressure dew point- 40℃ |
| food Packaging | 2 75kW centrifuges + 30m ³ gas tank | oil content ≤ 0.01mg/ m³ piping 316L stainless steel |
6. intelligent monitoring and optimization
-
energy efficiency management platform
deploy a compressed air management system (CAMS) to monitor flow, pressure, and power in real time, and identify energy-saving potential through big data analysis. -
dynamic speed control
using frequency converter and pressure sensor linkage, according to the gas demand automatically adjust the air compressor speed, energy saving rate can reach 15% -35%.
Conclusion
The determination of the gas volume of the compressed air system of the factory plant should follow the principle of “on-demand configuration, dynamic compensation, reserved expansion”, and achieve accurate matching of gas volume through scientific accounting and intelligent monitoring. Enterprises should establish an annual energy efficiency assessment mechanism, and continuously optimize the system configuration in combination with production changes, so as to ensure the continuity of production and reduce the operating cost of the whole life cycle.
