HYDAC Technical Training Manager Paul Marley points out that most industrial oils have a linear relationship between temperature and viscosity.
“In the viscosity calculator section of the HYDAC Tools app, the user enters temperature one and a viscosity reference point at that temperature, and then temperature two and a viscosity reference point at that second temperature. This establishes a gradient between the two points where at any other temperature the user can find out what the viscosity would be,” Mr Marley explains.
Heat loading
Heat load measurement is critical in cooler selection as an accurate heat load prevents cooler under-sizing and machine breakdown, HYDAC National Development Manager for Cooling Systems Andrea Cimadoro says.
Mr Cimadoro points out the following steps required to make a heat loading calculation.
Record the temperature increase: -Set the time to zero and record the initial temperature.
-Start the machine and record the ambient temperature and the temperature increase over a 30-minute time interval.
-Use the following tools for measuring purposes if need be: HYDAC HMG4000 (www.hydac.com.au/hmg-4000.html), infrared thermometer, visual temperature gauge, any other tool that can measure temperature rise accurately.
Calculate heat load: To calculate the heat load visit the Tools app on the upper right-hand side of HYDAC’s opening website page (https://www.hydac.com.au/) and then click on ‘calculator’ followed by ‘What would you like to calculate?’ and then ‘heat loading’, Mr Cimadoro explains.
Select the right cooler: Calculate the specific heat capacity. Use the specific cooling capacity formula:
P01 = Pv
__________________
T1 - T2
*Pv = heat load calculated in step two
*T1 = maximum oil temperature
*T2 = maximum ambient temperature
“Check out the heat dissipation curves in the catalogue to identify the cooler situation, keeping in mind that HYDAC recommends adding a safety margin when the cooler is selected,” Mr Cimadoro concludes.
Cylinder calculations
Mr Marley points out that the area of a circle is πr2 (or πr^2).
“Once you know the area of a cylinder bore, you can calculate how much force output you have when you apply certain pressure to it. If you know the bore, shaft diameter and stroke of a cylinder, then you can calculate oil volume inside it. And if you can calculate volumes over time you can calculate the flow rate required to actuate at that speed.”
For ease of use, 'pressure on the bore side’ and ‘pressure on the rod side’ units come in MPa, kPa and bar.
Pressure conversion
The pressure conversion calculator converts one unit of pressure to another unit of pressure. It converts between pounds per square inch, bar, pascal and kilopascal.
Volume conversion
The volume conversion calculator converts between litres, cubic metres, US gallons and Imperial (UK) gallons.
For example, one litre equals 0.0010m3, 0.26 US gallon, and 0.22 Imperial (UK) gallon.
“There are 1000 litres in a cubic metre and there are 3.785 litres per one US gallon, and users can find out so much more from the calculator,” Mr Marley exclaims.
Flow conversion
The flow conversion calculator converts the flow rate in one metric system to another (cubic metres per second, litres per second, litres per minute and litres per hour). This translates into 100m3/s converting to 100,000l/s, 6,000,000l/min, and 360,000,000l/h.
Measurement conversion
Measurement conversion is for working between linear measurements in inches, millimetres, centimetres and metres, explains Mr Marley.
“For example, there are 25.4 millimetres to one inch – that’s simple linear conversion,” Mr Marley says.
Gravitational force
Gravitational force, Mr Marley says, calculates force applied by a mass.
“To convert mass in kilograms to Newtons, the HYDAC Tools app will multiply by 9.81m/s^2,” Mr Marley concludes.