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Hello Everyone, I am designing an air bearing table with an internal air supply. The system has three flat air bearings each with a maximum flow rate of 1.32 NLPM at 0.41 MPa (60 psi). Instead of an external supply of air from a compressor, I am planning to supply air from a portable storage tank, so that i can make the system free from any external connections. I am facing difficulty to find the tank size and storage pressure. I did the following calculations For a 30-minute run Volume of air required by the bearings V1= 1.32 x 30 x 3 = 118.8 L at 1.01325 bar (P1) Now i can choose the tank volume V2 and can find the pressure P2 = (118.8x1.01325)/V2 Or i can choose the tank pressure P2 and can find the volume V2 = (118.8*1.01325)P2 can someone please verify if the calculation correct or not? I need to limit the tank size to the small canister of size 1L or 2L, so please suggest to me any air storage tank suppliers so that I can find out standard air storage canister sizes.

Hi Everyone,What is the difference between "Rated speed nC(1/min)" and "output speed" in servo motors.At the same time While "rated motor speed" is 1405(1/min) in gearbox catalogue, Rated speed is 3000 (1/min) in servo motor catalogue for the same gearbox.If someone has a knowledge about this kind of servo motor and gearbox, can you inform to me.Thanks in advance

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Its worth just trying out a standard thermal expansion coefficient calculation. (You have not stated the material that you are measuring) Take the material thermal expansion coefficient of the material you are working with and calculate its diameter for 30 degrees C...then calculate the same for 60 degrees C...I think you'll find a good correlation. Then just use the 60 degree figure for your measurements. Hope this helsp

With any motor, the power is from P = IV The power (in Watts) used is proportional to the voltage (in Volts) AND the Current (in Amps).....If you up your voltage, the ampage should drop significalty...as you've experimentally discovered, if the voltage is too low, the ability to supply a sufficient current (ampage) becomes the limiting factor. New (DC) motors are rated for a no load speed at a specific VOLTAGE...the current increases subject to the load to match the power requirements...and CRITICALLY the wire requirements are rated on CURRENT. If you run your motor at too low a voltage, your wires will overheat - both externally and internally - the varnish will evaporate from the winding wires inside the motor and the motor will either burnout through a resulting internal shortcircuit or catch fire! Hope this helps I shan't - at the moment - expand further as your experimentally discovering lots on your own which is by far the best way to learn....but I'll be happy to look again for additional questions. Good luck!

Okay...enough is enough...my turn! Assuming the chain links form a cyclic and therefore have a natural load-spread between both legs and no stress concentration: Stress = F/A Stress = 75 000 000 N/m^2, F = 50 000 N A = 50 000 / 75 000 000 = 0.000 667 m^2 for both legs A = (pi r^2)/2 per leg so r = root (0.000 333 / Pi) = 0.010 301 m d = 2r = 0.020 601 m = 20.601 mm - always round to the safety side....so: Therefore use 21mm dia stock minimum!

29.13mm

I'd agree with DrD....that said, ball-bearings are inappropriate in this application....I'd use taper roller as it has both an axial and radial component of force, otherwise - due to the mass of air, mass of the assembly and the resultant action - you will have premature bearing failure!

Hi,Lots of useful information. Thanks for sharing.

While this looks like a fairly simply problem on the surface, it has the potential to be quite complex. The fact that the shaft is vertical complicates the situation because it does not offer the stabilizing force of gravity. What you are asking for is professional work, well beyond the scope of the Q&A here at the ME Forum. You should contact a competent Professional Engineer for this assistance. You can send me a PM if you want further help. DrD

Hi All, I am Eko from Indonesia, kindly need your help to assist me to provide good reference ( with completed case study ) for Shaft Design & analysis, Special case : Vertical Arrangement Fan COoler Shaft as per attached filed, Many Thanks if you mind to help me ASAP regards Eko M

Shell, Technip, Saipem, Aramco

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Metric thread tightening Inch thread tightening