Pressure Unit Converter
Bar · MPa · kPa · Pa · PSI · atm · at · mmHg · inHg · N/mm²
Standard SI-derived conversion factors (1 bar = 100 000 Pa; 1 atm = 101 325 Pa).
Hardness Converter
Metals (HRC · HB · HV · tensile MPa) and elastomers / plastics (Shore A · Shore D · P&J)
Valid range: 20–65 HRC
Approximate conversion for hardened/tempered steel, based on standard reference tables comparable to ASTM E140 / SAE J417. Not valid for non-ferrous metals, case-hardened surfaces, austenitic stainless steels, or precision QC — always verify with calibrated instruments to the applicable standard. Tensile strength is a rough estimate only.
Roll Mass & Volume
Lateral & total surface area, volume and steel mass — for rolls, shafts and tanks
Material: steel
ρ = 7 850 kg/m³
Lateral area = 2πrh. Total area = 2πrh + 2πr² (includes both end caps). Mass uses steel density 7 850 kg/m³ — for hollow cylinder (shell only); set wall thickness = 0 for solid cylinder.

Roll Cover / Coating Mass
Layer 1
Range: 1.15–1.26 g/cm³