Submitted to: Applied Engineering in Agriculture
Publication Type: Peer reviewed journal
Publication Acceptance Date: 9/10/2003
Publication Date: 2/20/2004
Citation: Heping, Z, Butts, C.L., Lamb, M.C., Blankenship, P.D.. 2004.An implement to install and retrieve surface drip irrigation laterals. Applied Engineering in Agriculture. 20(1):17-23. Interpretive Summary: Drip irrigation has many advantages over other irrigation methods. It has been widely used in many applications throughout the world, resulting in crop yield increases and improved water conservation. However, the disadvantage of using surface drip irrigation is that users have to install and retrieve drip tapes every year, which requires high labor cost and time consumption. An implement to install drip tapes on or just beneath the soil surface to precisely irrigate crops after seeds are planted has been developed. Depth of drip tapes can be adjusted from top to just beneath the soil surface. The same implement can retrieve either reusable or disposable drip tape after crops no longer need irrigation for the season. When retrieving the drip tapes, they are distributed evenly across the rotating spools, which also squeezes out any remaining water. These drip tapes can be reused for subsequent growing seasons. To retrieve disposable drip tapes, a special spool was developed to quickly remove the tapes from the unit. No tools are needed for either installing or removing drip tape spools. The implement is inexpensive and performs both functions of installation and retrieval of drip tapes in one unit.
Technical Abstract: A surface drip irrigation tape installer/retriever was developed to install drip tapes on or just beneath the soil surface to precisely irrigate crops after planting, and to retrieve the drip tapes after irrigation is no longer needed for the season. The implement is mounted to the tractor using a three-point hitch and performs both functions of installation and retrieval of drip tapes in one unit. The retriever mainly consists of a speed reducer, a power transmission line, a drip tape distributor, drip tape spool supporters, water extractors and tensioners, drip tape guides. The installer mainly consists of a chisel, a press wheel, a tape depth adjustment screw, a tension spring, two soil cover plates, and a tangling prevention ring holder. During the installation process, drip tapes are placed in shallow trenches cut by the 5-cm wide chisel, and covered with soil by 6.5-cm wide pneumatic wheels. The depth of drip tapes can be adjusted from 0 to 5 cm under the soil surface. During the drip tape retrieval process, drip tapes are distributed evenly across rotating spools while any water in the tapes is squeezed out. The retrieval speed is adjusted by changing the tractor PTO speed. To retrieve disposable drip tapes, a special spool was developed to quickly remove the tapes from the unit. No tools are needed for either installing or removing drip tape spools. Mathematical models were developed to calculate drip tape length, retrieving time and spool sizes. Speeds of both retrieval and installation increased as the total number of laterals per ha decreased, or as the field length increased.