The nozzle itself is a constant valve (often closed valve, which means that the valve has been closed when there is no input control signal; and the valve is always in the open state when the control signal is not input), and a valve needle moves up and down to control the opening and closing of the valve. 

The VE type distribution pump is a single plunger type high pressure fuel injection pump, its structure characteristic is to use a set of oil supply elements to supply the diesel engine cylinder separately by the timing of the distribution mechanism. The VE distribution pump is an integrated body with fuel injection pump, governor, oil delivery pump and oil supply advance device. 

The design criterion of the fuel supply of a high pressure oil pump is the need to ensure the demand for the amount of fuel injection and the amount of oil controlled under any circumstances, as well as the change in the amount of oil when starting and accelerating.

Injector is a kind of precision device with high machining accuracy, which requires large dynamic flow range, strong resistance to clogging and pollution and good atomization performance. The injector receives the injection pulse signal sent by ECU to control the fuel injection accurately.

HEAD ROTOR is the part of the PUMP

Plunger composition: plunger pair is composed of plunger and plunger sleeve, with oil valve couple (composed of oil outlet valve and oil outlet valve seat). The plunger can be divided into A, B, K, AD, P and so on to meet the requirements of different diesel engines.

It is made up of two parts of the valve seat and the ball valve, and the fit gap between the two is only 3 to 6 microns.

The valve assembly is one of the main parts of the fuel injector.

Common Rail Repair Kit used in the maintenance of the injector.

It usually contains steel ball, adjusting shim, high pressure gasket, valve assembly, fuel injector connector etc.

The shim is a thin and often tapered or wedged piece of material, used to fill small gaps or spaces between objects.

Shims are typically used in order to support, adjust for better fit, or provide a level surface.

Shims may also be used as spacers to fill gaps between parts subject to wear.