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Demand
Demand refers to the flow of air at specific conditions required at a point or by the overall facility. In compressed air systems, “demand” describes how much airflow the environment needs at any given time to keep production moving, energize electrically powered tools or support end-use equipment. It changes throughout the day based on how often equipment runs, what tools are in use and whether multiple processes overlap.
When operators understand demand, they can adjust system controls, plan for peaks and keep equipment operating at its designated level.
A sudden rise in compressed air demand can cause pressure swings or inefficiencies if the system is not sized correctly. At the same time, low or inconsistent demand can leave equipment cycling more than necessary, which may shorten component life. The goal is stable, predictable operation through the right air compressor system design.
Many facilities calculate demand by reviewing how much air their tools and processes require during normal operation. This is often referred to as an air demand calculation, and it helps determine whether the system has enough capacity to maintain the pressure the environment depends on. Most operations use the following equation as part of their air demand calculations: ∑(tool flow × duty factor × simultaneity factor) + reserve + any leaks = air demand (total). Once operators know the actual airflow requirements, they can choose equipment that fits those needs while supporting future expansion.
When discussing air compressor demand, it is important to remember that flow is only one part of the equation. Pressure, piping, layout and duty cycles all influence how easily air moves through the system.
If you want guidance on sizing equipment or improving airflow distribution, our professional and knowledgeable air experts can answer your questions. Reach out or review our free resources, which include technical documents and product literature.
FAQs
A reliable air demand calculation gives operators a realistic picture of the facility’s airflow needs. This helps avoid undersized or oversized equipment. Undersized compressors struggle to maintain pressure, while oversized systems may cycle excessively. Both situations can increase operating costs. Accurate calculations reduce these risks and support long-term reliability. Calculations can also let facilities develop a management plan and ensure correct receiver sizing, both of which are important if demand varies widely throughout the day.
Air compressor system design must account for current demand and reasonable expectations for growth. Designers review flow rates, pressure drops, piping diameter and the overall layout. Systems that reflect true demand often show fewer pressure dips because air moves efficiently through the network.
A sudden rise in demand can lower system pressure. When this happens, tools may slow or lose effectiveness. In some cases, operators add storage or adjust controls to handle short bursts. If increases become routine, the facility may need additional equipment or a redesigned layout.
Flow meters make it easier to follow demand changes in real time. Many facilities also use routine walk-throughs to listen for leaks or note whether tools require higher pressure than usual.