How are you preparing for your MHM certification

gusto saludarles no dienen material didactico en español para la certificacion de mecanico hidraulico movil?

Actualmente, solo ofrecemos el examen en español.

There is no substitute for going through the study guide, before taking a prep class.

How The bi-directional axial piston pump work on single shaft?

I'm not sure I am understanding the question as I can think of three different ways the answer could go.  That being said, I will give you all 3 answers.

If you are asking how you would do bi-directional flow from an axial piston pump with the drive shaft turning in one direction of rotation then you would look at a Closed Circuit Hydrostatic Transmission pump which allows the swashplate to "go over center" which changes the flow from the unit: what was the outlet now becomes the inlet and what was the inlet now becomes the outlet.

If you are asking how do you change the direction of rotation on an axial piston pump then you typically would have to change the controls as well as the valve plate inside which has provisions for the new timing.

If you are looking to drive the pump shaft in both directions and have it act as a pump in both cases would require a number of modifications depending on the pump's design and manufacturer's requirements.

Could you please explain the terms of regarding closed circuit hydrostatic pump - "swashplate to "go over center" Thanks.
Suggest you google it if you didn't understand my previous response.  The swashplate physically moves over center from the previous angles of displacement.  Now the outlet flow becomes the inlet and the inlet becomes the outlet.  Shaft rotation doesn't change.  There are several Mobile Hydraulic textbooks to aid you in understanding.  We sell several different authored versions but I recommend the Eaton/Danfoss Mobile Hydraulics Manual.  You can purchase that on our website.  You may also want to consider taking a Basic Hydraulics course either online or instructor led.  Hope this helps.