Can any one help me to give the difference :

Advantages and dis-advantages between closed and open loop circuit in Hydraulics.

What is the best option and why.

rgds
Shaunzes

'Open and closed loop' can mean several different things. Not sure which question you are asking.

1. Open center or closed center valve, (gear pumps or variable piston pumps)

2. Open loop or closed loop ( pump return to tank, vs. hydrostatic loop)

3. Open loop or closed loop controls circuit (whether circuit has feedback and comparing to command)

I will try and attach a very small part of a power point on these three versions of the question.

ooops, can't it is 3mg. Send me a PM and I can email it too you.

kcj

ok, this should be better

temp2.ppt (117 Kb, 1402 downloads)

Q for the admin: what is the term 'darcy' below my name?

Thank Kevin for yr help.

Any way I wanted more details on the Closed loop Hydraulic and Open loop hydraulics.
Disadvantage and advantage.

rgds

Shaunzes,

The question you are asking is entirely based on the application. While Kevin is right in asking what type of closed or open loop you are talking about, I believe the advantages and disadvantages vary depending on application. For instance, a closed loop system when talking about the valve being open or closed center will determine what type of pump you sould use. You do not want to use a fixed displacement pump on a closed system (the center condition of your valve being closed). This would cause the volume of your pump to be discharged over your system relief and cause heating issues. Conversely, you don't want to use a variable displacement pump with an open center valve (center condition set as p to t) This would cause the pump to constantly flow and thereby negate the efficiency and power savings by using this type of pump. If you are talking about a closed loop where the fluid goes from the pump to the actuator and then back to the pump, one of the biggest advantages is being able to use a smaller reservoir. One of the biggest disadvantages is that the same fluid is being constantly used. This results in faster fluid breakdown. If you wish to know more, I suggest you contact Bud T. He can steer you in the right direction.