Thread Content
, Vacuum area division Vacuum area pressure range Torr (Torr) Pa (Pa) Low vacuum 760~10 101325~1333 Medium vacuum 10~10-3 1333~1.33×10-1 High vacuum 10-3~10-8 1.33×10-1~10-6 Ultra-high vacuum 10-8~10-12 10-6~10-10 Extremely high vacuum <10-12 <10-10 2. Length: Metric-imperial comparison table units meters (m) feet (ft) inches (in) 1 meter (1m) 1 3.28 39.37 1 foot (1ft) 0.305 1 8.33 1 inch 0.0254 12 1 3. Weight: Kilogram - pound - ounce comparison table unit kilogram (kg) pound (Ib) ounce (oz) 1 kilogram 1 2.2 35.27 1 pound 0.45 1 16 1 ounce 0.03 0.06 1 4. Comparison table of various vacuum gauges and regulations. Vacuum gauge name. Resistance vacuum gauge. Thermocouple vacuum gauge. 1. Hot cathode ionization vacuum gauge. 2. Pressure automatic controller. Cold cathode touch control vacuum gauge. Medium vacuum gauge. Ultra-high vacuum gauge. Name of regulation. Resistance gauge. Thermocouple gauge. Ionization gauge. Cold cathode gauge. Medium vacuum gauge. BA regulation. Regulation model. ZJ-52T ZJ-51 (DL-3) ZJ-53 ZJ-27 (DL-9) ZJ-2(DL-2) ZJ-10(DL-5) M014 DL-5 DL-8 ZJ-32 ZJ-32BC ZJ-12 5. Absolute temperature, Celsius, Fahrenheit temperature comparison table Temperature format K (absolute temperature) ℃ (Celsius) °F (Fahrenheit) K (absolute temperature) 1 ℃+273.15 5/9(°F+459.67) ℃ (Celsius) K-273.15 1 5/9(°F-32) °F(Fahrenheit) 9/5(K-459.67) 9/5(℃+32) 1 6. Pumping rate unit conversion table unit cubic meter/second (m3/s) liter/second (L/s) cubic meter/hour cubic foot/minute 1 cubic meter/second (1m3/s) 1 1000 3600 2118.88 1 liter/second (1L/s) 10-3 1 3.6 2.119 1 cubic meter/hour (1m3/h) 2.78×10-4 0.278 1 0.59 1 cubic foot/minute (1cft/min) 4.72×10-4 0.47 1.69 1 7. Resistivity (ohms) of various types of water Sea water Inferior tap water High-quality tap water Distilled water Ultra-pure water Resistivity 10~10-2 103 104~105 106 107~108 8. Molecular mean free path P (Torr) of 20°C air at different pressures 1 10-3 10-4 10-5 10-6 10-9 λ (cm) 4.72×10-3 4.72 47.2 472 4720 4.72×106 9. Commonly used pressure unit conversion table Pa Pa Torr Micrometer of mercury μmHg Microbar μbar Millibar mbar Atmospheric pressure atm Engineering atmospheric pressure am inches of mercury inHg pounds/inch2 lb/in2 1 Pa 1 7.5 ×10-3 7.5 10 10-2 9.86923 ×10-6 1.0197 ×105 2.953 ×10-4 1.450 ×10-4 1 Torr 133.32 1 103 1333.2 1.3332 1.31579 ×10-3 1.3595 ×10-3 3.937 ×10-2 1.934 ×10-2 1 μmHg 0.13332 10-3 1 1.3332 1.3332 ×10-3 1.31579 ×10-6 1.3595 ×10-6 3.937 ×10-5 1.934 ×10-5 1 μbar 10-1 7.5 ×10-4 7.5 ×10-1 1 10-3 9.86923 ×10-7 1.0197 ×10-6 2.953 ×10-5 1.450 ×10-5 1 mbar 102 7.5 ×10-1 7.5 ×102 103 1 9.86923 ×10-4 1.0197 ×10-3 2.953 ×10-2 1.450 ×10-2 1 atm 101325 760 760×103 1013.25 ×103 1013.25 1 1.0333 29.921 14.696 1 am 98066.3 735.56 735.56 ×103 980663 980663 ×10-3 0.967839 1 28.959 14.223 1 inHg 3386 25.4 25.4×103 3.386×104 33.86 3.342 ×10-2 3.453 ×10-2 1 4.912 ×10-1 1 lb/in2 6895 51.715 51.715 ×103 6.895×104 68.95 6.805 ×10-2 7.031 ×10-2 2.086 1 10. Air molecular density P (Torr) under different pressures 1 10-3 10-4 10-5 10-6 10-9 n0 (pieces/cm3) 4×1016 4×1013 4×1012 4×1011 4×1010 4×107 11. Main performance name of vacuum grease Ingredients Saturated vapor pressure at 20℃ (Torr) Maximum operating temperature (℃) 2# Polymer carbon 3.1×10-8 30 3# Oxygen compound 10-9 35 4# Soap grease 10-7~10-8 130 7501 Silicone oil plus silicon powder 10-6 or less -40~+200 12. Conversion of force units Dyne (Dyn) Newton (N) Stan kilogram force (kgf) 1 10-5 10-8 1.02×10-6 13. Power unit conversion unit horsepower kilowatt horsepower (PS) 1 0.735 735 kilowatt (kW) 1.36 1 1000 watt (W) 1.36 0.001 1 14. Vacuum sealing paste characteristics Vacuum grease name Vacuum sealing grease Vacuum sealing mud 50# 80# 30# Temperature 50℃ 80℃ 30℃ 10-7~10-8 Torr 10-7~10-8 Torr 5×10-4 Torr 15. Various Rubber Characteristics Table Rubber Type Natural Rubber Butyl Rubber Nitrile Rubber Fluorine Rubber Characteristics 1 Water resistance, acid resistance, alkali resistance, good permeability, small oil resistance, good 23 type strong acid resistance characteristics 2 Larger air output, serious sublimation, good elasticity, type 26, low permeability, low air output rate, small vacuum range, 1×10-5 Torr, 10-7 Torr, 10-8 Torr, 10-8 Torr, temperature -30~80℃ -30~150℃ -30~120℃ -20~200℃ 16. Area unit conversion square meter (m2) square centimeter (cm2) square millimeter (mm2) square foot (sc2) Square feet (ft2) Square inches (in2) 1 10000 1000000 9 10.7639 1550 17. Volume unit conversion Cubic meters Liter Cubic feet British Gallons US gallons (liquid) Cubic feet Cubic inches Sunrise 1 1000 27 219.98 264.18 35.3147 0.06103 554.37 18. Main performance indicators of No. 1 vacuum mechanical pump oil: Kinematic adhesion (centipoise) Flash point (℃) Saturated vapor pressure at 20℃ (Torr) Specific gravity (g/cm3) Molecular weight (g) KK-1 At 50℃ (47~57) At 100℃ (8~11) Not less than 15 Not more than 4×10-5 0.86 333 19. Domestic diffusion pump oil performance index brand 1# 2# 3# 274 silicone oil 275 silicone oil saturated vapor pressure (Torr) at 20℃ is not greater than 4×10-8 2×10-8 2×10-8 2×10-8 1.7×10-8 Kinematic viscosity (centipoise) 45~60 55~65 68~80 38±3 165±20 Freezing point (℃) is not higher than -15 -15 -15 -10 -14~-18 Flash point (℃) is not lower than 230 230 230 ＞210 ＞243 Specific gravity (g/cm2) 1.05~1.08 1.09±0.02 20. Types of vacuum pumps and their working range Vacuum pump working range (Torr) Vacuum pump working range (Torr) Rotary vane vacuum pump 760~5×10-4 Reciprocating vacuum pump 760~10-2 Slide valve vacuum pump 760~5×10-3 Adsorption pump 760~10-4 Oil booster pump 10-1~10-4 Sputter ion pump 10-4~10-10 Roots vacuum pump 10-1~10-4 Titanium sublimation pump 10-3~10-10 Oil diffusion pump 10-3~5×10-7 Molecular pump 10-3~10-10 Water ring vacuum pump 760~25 Cryogenic pump 10-3~10-10 21. Saturated vapor pressure of water at various temperatures Temperature Pressure Temperature Pressure ℃ Pa Torr ℃ Pa Torr -13 225.4 1.691 -10 386.5 2.149 -7 361.9 2.715 -3 489.6 3.673 0 610.4 4.579 3 757.8 5.685 7 1001 7.513 10 1228 9.209 13 1497 11.23 17 1937 14.53 20 2337 17.54 23 2808 21.07 27 3564 26.74 30 4242 31.82 33 5029 37.73 37 6274 47.07 40 7378 55.32 43 8638 64.80 47 10610 79.60 50 12330 92.51 53 14290 107.2 57 17310 129.8 60 19910 149.4 63 22840 171.4 67 27320 205.0 73 35420 265.7 77 41870 314.1 83 53400 400.6 87 62480 468.7 93 78460 588.6 97 90920 682.1 100 101325 760.0 101 104980 787.6 22. Melting point, heat of fusion, boiling point and heat of vaporization of some substances Melting point of substance (℃) Heat of fusion (Cal/g) Boiling point (℃) Heat of vaporization (Cal/g) Alcohol-114 23.54 78 204 Carbon disulfide-112 45.3 46.25 84 Ammonia-77.7 81.3 -33 327 Turpentine-10 80 160 - Ice 0 80 100 539 Naphthalene 80 33 218 50.5 Pig iron 1100~1200 8 2450 93 Carbon monoxide-200 46.68 -190 263 Acetic acid 16.6 16.4 118.3 104 Methanol-97.1 20.95 64.7 94 Aniline-6.24 30.24 184.3 124 Benzene 5.48 - 82.2 - Protein-96.5 - 56.1 -