**4.1.3.3 Valves**

The sprinklers are the equipments which the water quantity supplied to the processing and accordingly are used to adjust the pressure in irrigation systems. In general, the valves divided into manual and automatic valves. Manual valves can be listed as ball valves, gate valves, butterfly valves. In landscape irrigation, irrigation control is carried out with the help of automatic valves. The control valves used in the different points of landscape control the direction to various processing of the water in the system according to different requirements (Figure 2). The check valves that are installed sprinkler heads, they prevent back flow of water when the system is turned off.

Fig. 2. Control Valve and Application Sample

#### **4.1.3.4 Pressure gauge**

Operating pressure of sprinkler head within system requires to be obtained steady. Since changes such as increase or decrease to be occurred in operating pressure affect flow value to be ejected by heads, they prevent corresponding water diffusion from being provided. Due to over pressure to be applied in irrigation units, it causes occurrence of breakdown. In addition, probability of occlusion in fertilization tank can be detected through pressure gauge placed in front of and at the end of fertilization tank. Thus, pressure value is constantly kept under control through manometers to be placed in system control unit.

#### **4.1.3.5 Pressure regulators**

Pressure regulators are equipments that provide irrigation in constant volume, preventing pressure fluctuation within system. Inappropriate choice of pressure regulator for system

Depending on the source of water used in sprinkler irrigation system, irrigation water contains substances that can clog heads such as silt and organic matter. The filtration is performed to prevent clogging problems in short-and long-term in the system. Depending on the nature of water resources, it can be used to avoid clogging the heads of sand separator, hydro cyclone and disc filter. Due to mostly use of drinking water for landscape irrigation, filtering process is carried out with the disc or mesh filters. In sprinkler and drip

The sprinklers are the equipments which the water quantity supplied to the processing and accordingly are used to adjust the pressure in irrigation systems. In general, the valves divided into manual and automatic valves. Manual valves can be listed as ball valves, gate valves, butterfly valves. In landscape irrigation, irrigation control is carried out with the help of automatic valves. The control valves used in the different points of landscape control the direction to various processing of the water in the system according to different requirements (Figure 2). The check valves that are installed sprinkler heads, they prevent

Operating pressure of sprinkler head within system requires to be obtained steady. Since changes such as increase or decrease to be occurred in operating pressure affect flow value to be ejected by heads, they prevent corresponding water diffusion from being provided. Due to over pressure to be applied in irrigation units, it causes occurrence of breakdown. In addition, probability of occlusion in fertilization tank can be detected through pressure gauge placed in front of and at the end of fertilization tank. Thus, pressure value is constantly kept under control through manometers to be placed in system control unit.

Pressure regulators are equipments that provide irrigation in constant volume, preventing pressure fluctuation within system. Inappropriate choice of pressure regulator for system

irrigation systems, 80-120 mesh filters are usually preferred.

back flow of water when the system is turned off.

Fig. 2. Control Valve and Application Sample

**4.1.3.4 Pressure gauge** 

**4.1.3.5 Pressure regulators** 

**4.1.3.2 Filter** 

**4.1.3.3 Valves** 

causes to be defected by loading excessively over system units. Also, irregular, inadequate or high pressure cause breakdown of corresponding water diffusion and unnecessary additional irrigation. Pressure regulator generally used in control unit may be used before manifolds in main systems if required.

#### **4.1.3.6 Control units**

Operating units generated in pressurized irrigation systems have possibility of being operated on time and duration which is desired by the help of control units. As well as control units are used in garden-type small irrigation area having only one operation, the more developed ones can be done by means of a program which can operate several operations at the same time if requested. Electrical or wireless models of control units are used in areas in which electrise is problematic (Orta, 2009). If required, program used can regenerate irrigation program again by help of rain, wind and soil sensors placed in control units. Shut-down of system can be obtained by itself on the instant of rain through programming rain shutoff on control units. Also, it can prevent irrigation in case of soil`s having enough moisture by programming soil moisture sensors (Cardenas-Lailhacar et. al., 2008). Moisture sensors to be installed within working area provide more economic use of water, generating irrigation program.

Fig. 3. Control unit panel having 8 Station used in landscape irrigation Systems

#### **4.1.4 Delivery line**

Consist of pipes which deliver irrigation water from pump units to water emitters. A typical delivery line consists of main and lateral pipes and equipment which are used to tie those pipes. But submain and manifold are also included in great irrigation area.

#### **4.1.4.1 Main line**

They are pipes which transmit water from control units of water to submain canals if any, or to manifolds. Main canals carrying highest flow in system are manufactured as PVC and PE. Generally, 63-160 mm diameters are used depending on the size of system. They are the pipes in which frictional loss is at the most.

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pressure or increasing it causes deformation of water distribution in Figure 6. Changes of

It is not possible to provide uniform distribution in irrigating area by singular heads in sprinkler irrigation system. Uniform distribution is obtained by using more than one heads. Factors which affect water distribution are the sprinkler nozzle, operating pressure, flow rate, speed & uniformity of rotation, spacing of the sprinklers, pattern of the sprinkler grid and wind. What is required to be done after choice of appropriate head by purpose of providing uniform distribution is defining sprinkler pattern and sprinkler space. Heads are commonly lay out in shapes of triangle, square and rectangular. Triangular shape is used most commonly in landscape irrigation. In choice of triangular shape better water distribution is obtained in areas having equilateral triangle as compared to square shape. Water disposal is obtained in decreasing waste water due to its water distribution pattern `s being better as compared to square shape. Head in less numbers are used since sprinkler heads are placed to more distant area in triangular shape. Triangular shape presents better performance in irregular areas as compared to square shape (Melby. 1995). Another factor is distance between heads. For a good water distribution head intervals on lateral shouldn`t be more than 50% of dimension of wetted area. Also lateral intervals affect water distribution.

water distribution under different pressures are given Figure 6.

Fig. 4. Samples of using spray

Fig. 5. Samples of using Rotor

### **4.1.4.2 Submain line**

Submain pipes are the same type of pipes with main pipes. The highest cost in irrigation systems is cost concerning pipes and mainly main pipes. In choosing of irrigation pipes, pipes which have minimum capacity to meet requirements of flow in system should be chosen. By purpose of water distribution to be provided in different regions in major irrigation systems, dimensions of pipes are changed from a point which is broken into pieces from main pipes and by this way, disposals can be provided, using pipes which carry as need. These pipes transmit water taken from main pipes to manifolds.
