Hi All

I want to design my own spring loaded lubricator. The reason for this being is that the only off the shelve lubricators come in capacities of 125 ml and 220 ml max. I would like to create a 2000 ml spring lubricator.

I have first designed a spring with spring constant k = 22000 N/m.
With the spring constant k I want to calculate the force required to compress the spring by 200mm.
The piston attached to the spring has an area of 0.01 m^2.
The pressure then to compress the piston+spring will be P = F/A = +- 400000 Pa = +- 4 BAR. (Am I right?)

The grease that I am using is of NLGI 2 with density = 870 kg/m3.. My questions are as follows?

If the spring is compressed by 200mm with grease, what will the pressure be of the grease inside the container?
If I open the flow valve underneath the container, will the spring force be enough to exert the grease out of a 10mm hole?
How do I calculate the flow rate of grease from the container through a opening of 10mm?



Thanks in advance!

 

Hey Zenex,

You could do some trials just to be sure, but if I were you I would download the SKF DialSet software which helps calculate lubrication units based on their operating conditions. I would suppose that the temperature of the grease would play a huge role in the dispersion rate since the viscosity would change. Also, it would be hard to achieve a constant dispersion rate for a multitude of reasons. Check this post which contains some basic calculations that could be helpful to you at this point: https://www.engineeringclicks.com/compression-springs/