In order to ensure excellent drip irrigation system performance, routine maintenance of the system has to be planned.
Regardless of recent innovations in drip irrigation system design that, among other things, make drip lines remarkably resistant to atmospheric events and malfunctions due to clogging, maintenance keeps being a priority.
Indeed, a filtration system by its nature has a limited duration in time and is subject to wear. In the same way, the use of fertigation can easily cause clogging, too.
Clogging of the irrigation system may cause damage to the current crop that would not receive a sufficient water amount. This would endanger an important economic investment that would not see a return on investment due to incorrect crop growth.
The reference readings and constant monitoring of the flow rate, pressure and cleaning water conditions can provide important indications on how to schedule maintenance interventions.
In addition to these values, pumping system and distribution system conditions will have to be inspected and calibrated. For this reason, control units, engines, injectors, pipes, valves, fittings, flow meters and pressure gauges should be checked.
In case of malfunction or breakage of one of these system components, it will be necessary to replace it with an identical or similar device in order to comply with the system design
criteria and to guarantee the unchanged performance of its functions.
Maintenance interventions suggested by SAB
- Control of the pump flowrate and pressure for each sector of the system;
- Check for any pressure losses through the filters;
- Control the pressure at the end of lateral lines;
- Check the presence of water at the end of the lateral lines or on bleeding valve;
- Control the pumping station;
- Adjust the injection pump correctly;
- Check the general conditions of the system.
Control of the pump flow rate and pressure for each sector of the system
The control of the pump flow rate and pressure for each sector of the system must be carried out at least once a week. It is necessary to verify that these values comply with the reference values detected at system launch and reported by the installation supervisor. If the flow rate increases or a pressure loss is detected, or vice versa, it will be necessary to identify the cause and then verify that:
- there are no leaks in the main pipes or in the lateral lines;
- the bleeding valve is open;
- the sector valves are not closed.
Check for any pressure losses through the filters
The presence of any pressure loss through the filters must be checked at each irrigation cycle. Indeed, a malfunction of the filtering system would cause inadequate irrigation as the crops do not receive the right water requirement. In order to function properly filters must always comply with the specifications indicated by the manufacturer. When the maximum tolerable value is being exceeded or approached, it indicates the presence of a filter occlusion.
Pressure control at the end of the lateral lines
The pressure at the end of the lateral lines must be checked at least monthly and must always be equivalent to the reference pressure indicated by the installation supervisor and detected during the drip irrigation system launch. If the pressure value is higher or lower than the reference value, one of the following scenarios may have occurred:
- clogging / obstruction of the drip tape;
- damaged lateral lines;
- low pressure of the entire system.
Check the presence of water at the end of the lateral lines or on the purge air valve
The check of the presence of water at the end of the lateral lines or on the bleeding valve must be carried out at least twice a week. In particular, it is necessary to check the presence of detritus or solid particles in the water. If one of these two hypotheses occur, you should check that:
- the pipes are not damaged;
- net filters are not damaged;
- the filtering mass is not able to block the particles as they are too small;
- the filters are not damaged;
- there is no leakage of fertilizers;
- there is no algae or bacteria.
Control of the pumping station
The pump station must be checked at least weekly as it must always comply with the specifications indicated by the manufacturer. It is necessary to check that there are no leakages or breakages and that the reserve level of the engine and the tank level comply with the indicated technical specifications.
Correct adjustment of the injection pump
The injection pump adjustment must always be set at system launch and must be checked weekly. This control is necessary in order to ensure an adequate injection duration time setting and the correct pump functioning.
Check the general conditions of the system
A general check of the well-functioning of an irrigation system must be carried out weekly to verify that the settings at the launch are unchanged. The discoloration of the emitters or of drip tapes, the presence of leakages in the drip tape or a stressed crop may indicate one of the following conditions:
there are no pump malfunctions and the well supplies the right amount of water for irrigation.
- and / or bacterial mud;
- mechanical or parasite damage;
- drip tapes disconnected from the fittings;
- burst of the drip tape due to overpressure;
- crops suffering from some diseases;
- clogged, obstructed or damaged tape;
In addition to adjusting and repairing the necessary system parts some activities, such as submission of necessary chemicals, system cleaning and parasite check are to be considered.
