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Cost, Tolerances & Reference

Pressure Unit Converter

CNC tool holder runout tolerance specification. Get instant bar, psi, MPa, kPa, atm, kgf/cm² for your machining parameters.

Input Parameters

Results

bar
psi
MPa
kPa
atm
kgf/cm²
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The Engineering Behind Pressure Converter

Every seasoned CNC machinist knows that getting the numbers right means the difference between scrap and a perfect part. Pressure Converter is no exception. When Mapal application engineers walk a customer through process optimization, this is one of the first parameters they check — because even a 5% error here can cascade into tool failure or out-of-tolerance parts.

The formula at work here is deceptively simple but carries deep implications. Korloy publishes reference tables for this parameter across their full material catalog, and TaeguTec integrates it directly into their ToolGuide app. The underlying principle hasn't changed in decades, but modern coated carbides have pushed the usable range significantly.

Engineering Note

Always cross-reference your calculated values against your tool manufacturer's recommended ranges. Mapal's CoroPlus ToolGuide and Korloy's NOVO app provide material-group-specific upper and lower bounds. When in doubt, start conservative — you can always push harder on the second part.

Worked Example: Step-by-Step

Scenario: Machining 4140 alloy steel (HB 280) on a Grob VMC, using a Mapal solid carbide end mill.

Step 1 — Gather inputsDiameter 12mm, SFM 180 Step 2 — Compute RPMRPM = (180 × 1000) / (π × 12) ≈ 4,775 Step 3 — Apply to the formulaFeed = 4,775 × 4 × 0.05 = 955 mm/min Step 4 — VerifyChip load 0.05 mm/tooth ✓

Pressure conversion formulas

Pressure units vary by industry and region. Coolant systems use bar, hydraulics use psi or MPa, and vacuum systems use kPa. This converter handles all common engineering pressure units.

Frequently asked questions

What pressure unit should I use for CNC coolant?

Bar is standard for coolant pump specifications. Most high-pressure coolant systems are rated in bar (20, 40, 70, 80 bar). Through-tool coolant typically requires 20-80 bar for effective chip evacuation in deep-hole drilling.

How do I convert machine hydraulic pressure to clamping force?

Clamping force (N) = pressure (MPa) × piston area (mm²). Example: 5 MPa hydraulic pressure on a 50 mm diameter piston (1,963 mm²) = 9,817 N (≈1,000 kgf) of clamping force. This calculator handles the pressure unit conversion step.

What is the difference between gauge and absolute pressure?

Gauge pressure (barg, psig) is relative to atmospheric pressure. Absolute pressure (bara, psia) includes atmospheric pressure. Gauge = absolute − 1.013 bar at sea level. Almost all shop-floor measurements are gauge pressure.

How to use this Pressure Unit Converter

Enter a value in any of the supported units. The converter displays equivalents in bar, psi, MPa, kPa, atmospheres, and kgf/cm². Use this for coolant system setup, hydraulic pressure checks, and pneumatic system specifications.

Common mistakes to avoid

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