machines that are used to create drainage on lands being reclaimed and irrigated, as well as on peat bogs. Drainage machines are distinguished by the method of installation of drains into the soil (trench, narrow-trench, and trenchless), according to which their structures are distinguished by the type of working member, by devices for shaping pipes, and by general configuration (self-propelled, tractor-mounted, or trailer).
A drainage machine whose working member is a bucket chain is used for the trench method. Operations for installing drains by the trench method by means of a drain-layer consist of digging the trench and installing a filter and drainpipes. The drain-layer-excavator, which has a caterpillar drive, digs the trench with buckets (the soil from the buckets is fed to a band conveyer and is unloaded onto a pile beside the trench) or with scrapers, which bring the soil to the surface, where it is leveled by screw conveyers. Along the trough of the pipe-layer (mounted behind the bucket frame), ceramic pipes are laid down close to one another on the bottom of the trench, which has been prepared in advance by a clearing block. The trench is filled in first by hand and then with a bulldozer. Pipe-layers are sometimes equipped with a glass-fabric coil, which is laid under the pipes and acts as a protective and filtering material.
In the narrow-trench method, pipe is laid in a trench not wider than 25 cm simultaneously with the excavation of the trench. Multiscoop narrow-trench excavators with chain, scraper or bar, rotor, and screw conveyer operating units are used. Ceramic or plastic pipes are laid as the trench is being dug. The slope of the trench bottom is maintained automatically. The operator feeds drainpipes into a laying chute manually or by means of accessory devices.
In the trenchless method, plastic pipes are laid on the bottom of a narrow cleft (up to 2.5 m deep) cut with a haft blade. Machines for shaping pipe from bands, with simultaneous laying of the pipe, have been developed in the USSR. The band passes from a coil fastened behind the blade through a pipe-shaping device; lap joints are fastened by perforating sprockets, which simultaneously punch waterintake holes, or by shaped notches (“lightning” joints). The pipe is placed on the bottom of the trench or cleft. Mole drains are laid by tractor-mounted mole plows. The working member of mole plows is a blade with a fairing on the end to which a drainer is fastened by a hinge or cable; the drainer squeezes out a hollow—called a mole drain—in the soil.
REFERENCESMer, I. I.Meliorativnye mashiny. Moscow, 1964.
Riabov, G. A., I. I. Mer, and G. T. Prudnikov.Meliorativnye i stroitel’nye mashiny. Moscow, 1968.
Kazakov, V. S., and E. D. Tomin. Mekhanizatsiia stroitel’stva zakrytogo drenazha na osushaemykh i oroshaemykh zemliakh. Moscow, 1969.
L. M. MALKOV and I. I. MER