There are two ways of lubrication types for the dual line lubrication systems:

Lubricate Types In Dual line Lubrication System & Equipment:
1. By Hand Operationp2-2
Two types of power the lubrication system: manual hand pump, it is equipped with a manual directional valve, when the operation pressure increasing sharply, the system can be controlled by manual to lower the pressure or keeping it in a normal pressure. The manual type is simple and low cost is available for the occasions of long terms grease feeding and less lubrication points.

2. By Electric Power
There are three types as electric powers control
Electric Terminal type:
The signal is send by terminal pressure valve (or pressure differential switch), change the directional valve spool position by electrical control unit.
This type uses the terminal pressure as the control parameters of system pressure, it is suitable for lubrication points where spread wider occasions. The type is lower pipe installation costs.

Hydraulic Direction Terminal Type:
This type is directly controlled by the directional valve outlet pressure, without end pressure (difference) signals and electrical control.
The system uses a directional valve outlet pressure as the control parameter, therefore, the hydraulic pressure presetting should refer to the numbers of lubrication points on-site. The type is piping installation at lower cost, simplified control method.

Hydraulic Directional Loop Type
The directional control by loop terminal pressure of directional control valves, the direction movement does not need pressure and electric signal, only assembly loop circuit with directional valve.
The system uses a loop end pressure grease as a system control parameters to feed grease, it is piping installation costs are relatively high, suitable for lubrication points are concentrated occasions.