Figure 2- 1 Types of flat construction machinery
(1) plate machinery
Leveling machinery refers to machinery that needs to be reclaimed before planting a large lawn, such as excavators, bulldozers and graders.
① Excavator. Excavators, also known as excavators (Figure 2-2), are earth-moving machines that use buckets to excavate materials above or below the bearing surface, load them into transport vehicles or unload them into the storage yard. In lawn planting, excavators mainly dig soil, sediments and rocks.
Figure 2-2 Excavator
② Bulldozer. Bulldozer (Figure 2-3) is a kind of construction machinery for shoveling earthwork, which is suitable for short-distance earthwork shovel operation. Bulldozer is mainly composed of bulldozer and hydraulic lifting system, which is composed of bulldozer, beam, hydraulic cylinder, oil pump, oil tank and distributor. Tractors for bulldozers are divided into wheeled tractors and crawler tractors. According to the composition of hydraulic lifting system of bulldozer, the bucket of bulldozer can be lifted vertically, obliquely, horizontally and obliquely, and the ground can be pushed into a certain slope and shape, and the shoveled soil can also be piled into a certain shape. Bulldozers with these functions are called molding machines in lawn and golf course engineering. Generally, bulldozers used in site leveling projects only have vertical lifting hydraulic systems, but there are no tilting lifting and tilting translation hydraulic systems. This bulldozer can also be used for lawn leveling and modeling, but the effect is not as good as that of multifunctional molding machine.
Figure 2-3 Bulldozer
③ Motor grader. A motor grader (Figure 2-4) is a machine with a fine flat ground. The main working part of grader is shovel. Compared with bulldozers, graders are suitable for flat operation with small ground elevation difference, but not for the ground with micro-topography fluctuation and many slope changes. This machine is mainly used for highway subgrade leveling, and can also be used for large square lawn ground if the flatness is required.
Figure 2-4 Grader
(2) Farmland machinery
Farming machinery refers to machinery that can turn up the ridge and destroy the original soil structure, such as plowshare, disc plow, rotary tiller and so on.
(1) share. Ploughshare is a widely used agricultural machinery. Its function is to turn over and break the soil ridges, cover vegetation and eliminate weeds and eggs. As shown in Figure 2-5, a four-share plough is hung.
Figure 2-5 Ploughshare
② Disc plough. Disc plow is a plow that uses concave discs as working parts to turn and break soil (Figure 2-6). There are ordinary disc plow, bidirectional disc plow and vertical disc plow. When plowing, the disc rolls forward under the action of soil reaction force and cuts the soil with its cutting edge. The soil cut by the disc is loose and broken in the process of rising along the concave surface of the disc, and finally turns into the furrow. Disc plough has strong ability to cut off grass roots and stubble, and it is not easy to be blocked. It is mostly used in ploughing operations such as wetlands, grasslands, peat soil and green manure fields.
Figure 2-6 Disc Plough
③ Rotary cultivator. Rotary tiller is a kind of soil tillage machinery driven by power (Figure 2-7), and its function is to break and loosen soil. Unlike iron harrows, rotary cultivators can mix soil. When the rotary tiller is working, the rotary tiller teeth chop up the soil and throw the cut clods backward, which will collide with the cover plate to break the soil. Rotary cultivators have a wide range of applications and can be used in various soils. Rotary tillers are characterized by strong ability to turn over and break the soil, loose soil and flat ground after ploughing. Fertilizer or soil improver is applied before ploughing, and the fertilizer on the surface is evenly mixed into the soil through rotary tiller operation, which can generally meet the requirements of lawn planting in one operation. The disadvantage is that the tillage depth is shallow and weeds cannot be removed. Work tools are directly driven by tractors, which consumes high power.
Figure 2-7 Rotary Tiller
(3) Soil preparation machinery
Refers to machinery for dressing soil or ground shape on cultivated land, such as disc harrow, nail harrow, compactor, etc.
① Disc harrow. Disc harrow is a kind of tillage machinery used to break and loosen soil, which is composed of several spherical discs. After ploughing the land, the solid soil will form large clods, and there may be incomplete ploughing ridges. Use harrow to further prepare soil to meet the requirements of turf building.
There are three suspension modes between the disc harrow and tractor: traction, suspension and semi-suspension. The structure of disc harrow is mainly composed of front harrow group, rear harrow group, harrow frame and hook device (Figure 2-8). Some disc harrows are also equipped with angle adjusters to adjust the deflection angle of the harrow group. The harrow group is the working part of the disc harrow, and the harrow frame has two types: articulated and rigid, and the harrow frame transmits the traction of the tractor. The harrow frame is equipped with disc harrow group, adjusting mechanism, suspension mechanism and other components. Some harrow racks also have load boxes and counterweights to increase and maintain the harrow depth. In order to adapt to different rake depths, the angle adjuster requires that the deflection angle of the rake group can be adjusted, which is generally realized by the angle adjuster. Hook device is the connecting part between rake and tractor. On the suspension rake, the suspension device consists of a suspension frame and a suspension shaft. The depth and broken soil quality of disc harrow are related to the rake deflection angle, which is large, deep and good.
Figure 2-8 Disc Rake
② Rake. Rakes are used to break topsoil, level the ground, remove weeds and cover seeds after sowing. The nail tooth harrow is mainly composed of nail teeth, harrow frame and suspension mechanism (Figure 2-9). The nail teeth are fixed on the toothed bar, which are round, triangular and square according to their shapes. Square teeth are easy to fix, stable in work and most widely used. Triangular teeth are mainly used for weeding lawns besides raking the ground. Round teeth are suitable for covering and raking weeds after sowing.
Figure 2-9 Nail harrow
③ Ballast. The main function of the compactor (Figure 2- 10) is to flatten the lawn residues and green manure in front of the cultivated land, creating conditions for ploughing; Compaction after ploughing: the clods can be crushed, and the loose plough layer can be compacted to prepare the seedbed for sowing; Repression after sowing or lawn planting can make the seeds or lawn closely contact with the soil, which is beneficial to improve the germination rate of seeds and the survival rate of lawn grass.
Figure 2- 10 ballast
The use of compactors must be carefully selected according to specific conditions such as soil, climate and lawn. If used improperly, it will be harmful. For example, if the soil moisture is too high, it will harden the soil and affect sowing and seedling emergence.
Most commonly used ballasts are traction type, which are generally divided into V-shaped, mesh ring-shaped and cylindrical according to different shapes.