Compressor Sizing Guide

コンプレッサタイプエアコンプレッサエアコンプレッサの選択圧縮空気Wiki 方法

最大の問題は、新しく購入するエアコンプレッサの正しいサイズを決定することです。市販されている新型のコンプレッサは技術と効率が向上しているため、用途と使用方法を理解して正しいサイズを決定する必要があります。お客様の設備に合わないコンプレッサを選択してしまうと、生産において問題が発生し、無駄なエネルギーが原因となってコストが増加することがあります。

How to Size an Air Compressor

Determining the right size of an air compressor involves a few essential steps:

Identify Your Tools and Their Requirements: Make a list of all tools and equipment that will be using the air compressor. Check each tool's CFM and PSI requirements.
Consider the Duty Cycle: Assess how often and how long each tool will be used. Continuous operation tools will need a compressor that can handle longer duty cycles.
Account for Future Expansion: Think about any potential future tools or increased use. It’s wise to choose a compressor that can handle more than your current needs to avoid outgrowing it quickly.

Want to know more about Airflow, Pressure, Applications, and Power? In the following section, we will explain what each of the compressor selection criteria means and answer some questions you might have.

Compressor Selection Criteria

Selecting the appropriate compressor involves considering several criteria:

Airflow (CFM): Determine how much airflow (cubic feet per minute) is required for your applications. This is a critical factor as it indicates the volume of air the compressor can deliver. Different tools have different air tool CFM requirements, making it essential to understand your specific needs.
Pressure (PSI): Identify the necessary pressure (pounds per square inch) for your tools and machinery. Various applications will have distinct PSI needs.
Application: Consider the specific applications and air quality requirements. Take into account any pressure loss due to dryers, filters, or drains. This includes evaluating whether you need a high-pressure compressor or one suited for spray painting or other specific tasks.
Power (HP/kW): While important, power is not the primary selection criterion. Focus on airflow and pressure first, and then match the compressor’s horsepower (HP) or kilowatts (kW) to your needs.

Understanding Air Compressor Capacity and Flow Rate

自由空気吐出量（FAD）とも呼ばれる空気量は、お客様の地域により立法フィート/分（cfm）、リットル/秒（l/s）、または立法メートル/時（m3/h）単位で測定します。端的に言えば、空気量とは、許容される時間枠内で継続してタスクを実行するコンプレッサの能力です。必要な空気量の量は、与えられた作業の完了に必要な時間長によって決まります。これを説明するために、先の木製ブロックの例を考えてみましょう。木製ブロックを1時間あたり一定の距離を動かすために必要な空気量は、先の例よりも低く、より小型のコンプレッサと貯蔵タンクを使用して達成できます。

コンプレッサは循環を繰り返し、次の木製ブロックを動かす必要が出てくるときに備えて、貯蔵タンクを再充填します。ただし、木製ブロックを与えられた時間内で継続して動かす必要がある場合には、より大きな空気量（またはcfm）で連続させることが必要となり、より大型のコンプレッサが必要です。

空気量が不十分な場合、このプロセスでは、コンプレッサ貯蔵タンクの圧力が上昇する間、頻繁に休止させることが必要になり、これはコンプレッサのサイズが小さすぎるということを意味します。

What is the right air flow for my compressor?

Airflow, also known as free air delivery (FAD), is measured in cubic feet per minute (cfm), liters per second (l/s), or cubic meters per hour (m³/h) depending on your location. Simply put, airflow determines how effectively a compressor can perform a task within an acceptable time frame. The required flow depends on the duration needed to complete a task.

For example, moving a wooden block a short distance every hour requires less flow and can be managed with a smaller compressor and a storage tank. The compressor cycles on and off, refilling the tank for the next task. However, the constant movement of the block necessitates a larger, continuous flow (higher cfm), thus a larger compressor. Insufficient flow means frequent breaks for pressure buildup, indicating an undersized compressor.

Rotary screw air compressors generally provide more flow per kW or HP than piston compressors.

Summary:

When sizing a compressor, consider the specific requirements of the job:

Pressure (PSI): Dictated by the type of task being performed.

Flow (CFM): Depends on the frequency and number of simultaneous tasks.

Undersized Compressor: Results in pressure drops and incomplete tasks.

Oversized Compressor: May cause mechanical issues and failure.

For accurate sizing of your compressor for new or existing applications, always contact a compressed air sales professional for an audit.

必要な圧力

Understanding the flow and pressure requirements for your facility is key when choosing an air compressor. Pressure and flow are common terms used when discussing compressed air systems.

Pressure can be measured in pounds per square inch (psi) or bar (metric measure of pressure). Simply put, pressure refers to the amount of force needed to perform a certain amount of work at any given point in time.

For example, imagine moving a wooden block across a table: Using 100 psi of compressed air is not enough force to move the block. However, 115 psi of pressure can move the wooden block the desired distance.

See the difference between PSI, PSIA and PSIG

What is the difference between psi, psig, psia?

The air compressor must provide enough pressure to perform a given task. If 115 psi is required to move the block, anything less will not accomplish the task. It is important to understand the required pressure to size the compressor properly. Otherwise, you may face issues similar to the illustration, where lower pressure fails to move the wooden block or perform the job.

Applications and CFM/PSI Requirements

When determining the right compressor, consider both the amount of compressed air flow (cfm) needed and the specific pressure (psi) required for the process. Different tools and applications require specific CFM and PSI levels.

Below is a chart with common tools and their requirements:

Applications	CFM	PSI	Air tools	CFM	PSI
Home Use	1-2	70-90	Airbrush	0.5-1.5	20-30
Spray Gun	4-8	30-50	Nail Gun	1-2	70-90
Spray Painting	4-8	30-50	Dental Equipment	2-4	80-100
Sandblasting	6-25	70-90	Tire Inflator	2-3	100-150
Various Power Tools	3-10	90-120	Impact Wrench	3-5	90-100
HVAC Systems	6-12	80-100	Air Ratchet	3-5	90-100
Refrigeration	3-5	60-80	Hammer Drill	3-6	90-120
Automotive Assembly	8-15	90-120	Paint Sprayer	6-7	30-50
Food and Beverage Packaging	4-10	70-90	Grinder	5-8	90-120

Common questions when buying a compressor

How much CFM do I need for an air compressor?

The CFM required depends on the tools or applications you will be using. Refer to the above chart for specific requirements.

What size air compressor do I need for home use?

For home use, the CFM and PSI requirements are generally lower. Typical applications include inflating tires, operating small tools, and spray painting. Ensure you match the compressor to your most demanding tool.

What size air compressor for spray painting?

Spray painting requires a compressor that can deliver steady airflow at a relatively low pressure. Generally, a compressor with 4-8 CFM at 30-50 PSI is suitable.

What Type of Compressor Do I Need?

What Type of Compressor Do I Need?

Find out what compressor is best suited for your needs.

Do I Need an Oil-free or Lubricated Compressor?

Do I Need an Oil-free or Lubricated Compressor?

Find out whether or not you need an oil-free compressor, or if a lubricated compressor will do the job.

Other factors to consider

Air Quality: Depending on your application, you might need oil-free or oil-lubricated compressors.
Energy Efficiency: Consider compressors that have validated energy efficiency ratings to save on operational costs.
Portability: Determine if you need a stationary or portable compressor based on your workspace and mobility needs.
Noise Levels: Some compressors operate more quietly than others, which can be essential in noise-sensitive environments.

Find more helpful information in the "Guide to Selecting the Optimal Compressor for Your Needs" ebook or contact us for personalized assistance. Our experts are available to help you determine the best compressor for your operations.

最終的に、与えられた用途に対して十分な圧縮空気を供給するには、プロセスが適切に働くために必要な圧力で必要な圧縮空気量（cfm）を考慮することが重要です。

必要な総空気量を確認する方法の1つは、圧縮空気を使用する機器のメーカーに連絡して、必要な情報が記載されているデータシートを要求することです。ただし、空気量を正確に測定するには「エア診断」を実行するのが最善であり、これは圧縮空気の営業担当者が行うことができます。ロータリスクリュエアコンプレッサは、kWまたはhpあたりの吐出フローがピストンコンプレッサより大きくなる傾向があることに留意することが重要です。

まとめると、圧力（psi）は実行する仕事により決まるのに対して、空気量（cfm）では、仕事をどの程度頻繁に実行するのか、またはいくつの作業を同時に実行する必要があるのかを把握する必要があります。サイズが小さすぎるコンプレッサを選択すると、圧損が生じて作業を完了できず、コンプレッサのサイズが大きすぎると、将来に機械的な問題が発生し、コンプレッサが故障する可能性があります。既存の用途や新規用途に必要な新しいコンプレッサのサイズをどのように設定すればよいか分からない場合は、圧縮空気の営業担当者に連絡してエネルギー診断を依頼してください。

Volume Conversion Calculator

A volume conversion calculator can assist in air compressor sizing calculation accurately. It helps convert different units of measurement to ensure the compressor meets your specific needs. Using this tool can simplify the process of determining the correct size.

コンプレッサには、あらゆるタイプとサイズがあります。大型の生産設備で稼働を続ける大型コンプレッサから、DIY 好きが使用する小型のコンプレッサまで、さまざまな種類のコンプレッサがあります。たくさんのモデルから最適なコンプレッサを選択することができますが、お客様に最適なコンプレッサはどれでしょうか？　

アトラスコプコのエキスパートへお任せください。

お客様に最適なコンプレッサを見つけるお手伝いをいたします。