In the drip trickle irrigation system, the device that transforms the pressure water flow in the capillary tube into drips or fine streams through channels or orifices is called dripper heads. The dripper heads are mostly made of plastic, and the commonly used flow rate is 1-4 liters/hour, generally not exceeding 12 liters/hour.
The quality of dripper heads directly affect the reliability and water quality of drip irrigation system. Therefore, the dripper heads is often referred to as the "heart" of drip irrigation system.
The flow rate of the dripper heads should be small
Drip trickle irrigation is a local irrigation method that requires a small flow rate of dripper heads. The flow rate of the dripper heads depends on the working water head, the size of the cross section of the water flow channel and the flow resistance.
The flow of the dripper heads should be even and stable
Under normal circumstances, the flow rate of the dripper heads changes with the size of the working water head. In order to ensure the uniformity of water application in drip irrigation system, the dripper heads structure should be able to minimize the sensitivity of flow rate to pressure, so that the change of flow rate is small when the pressure changes.
The dripper heads should have good anti-blocking performance
There are always some impurities in the irrigation water, because the flow channel of the dripper heads is small, anti-blocking measures should be taken in the design and manufacture of the dripper heads to improve their anti-blocking ability.
The manufacturing accuracy of the dripper heads should be high
In the drip irrigation system, the size of flow rate change of the dripper heads is affected by the manufacturing accuracy. If the manufacturing deviation is too large, the relative difference of flow cross section size of each dripper heads will be very large, and the flow rate difference of dripper headss in the system will increase and the system uniformity will decrease. Therefore, in order to ensure the water quality of drip irrigation, the manufacturing deviation coefficient Cv value of the dripper heads should generally be less than 0.07.
The dripper heads should be easy to manufacture and install
The structure of dripper heads should be simple, easy to manufacture, install and clean, and at the same time they should be strong and durable.
The dripper heads should be low-priced
The price of dripper heads has certain influence on the system cost because of its large usage in micro-irrigation system.
In fact, most dripper headss are not easy to meet all these requirements at the same time. Therefore, when choosing dripper heads, it should be selected according to the specific use conditions. For example, when using ground water sources with poor water quality, the anti-blocking performance of dripper heads should be higher, while when using relatively clean well water and spring water, the anti-blocking performance requirements of water distributor should be correspondingly lower.