Technology of construction processes during construction of 17-storey monolithic residential building

Contents

1. Introduction of pages

2. Agrotechnical requirements for the machine and its working bodies pp

3. Analysis of existing machines or working bodies of similar purpose pp

4. Justification and selection of new structure of pages

5. Process calculations of pages

6. List of used literature pp

Introduction

The main tasks of the agro-industrial complex: achieving sustainable growth in agricultural production, reliable provision of food and agricultural raw materials to the country, combining all sectors of the complex to obtain high final results. In s/x, it is possible to increase the average annual volume of gross output by 1416% mainly due to intensive development factors and the introduction of the latest achievements in science and technology, the effective use of the created production potential.

To continue the consistent development of scientifically based farming systems, expand the use of soil protection methods for land cultivation and carry out erosion control measures in the farm. To significantly increase the productivity and sustainability of agriculture, to this end, implement a set of measures to increase soil fertility and introduce intensive technologies for cultivating agricultural crops.

On the basis of chemization - the use of organic fertilizers, systematically carry out work to increase soil fertility. To study storage, improve storage and methods of application to the soil, increase the effectiveness of the use of fertilizers and chemical means of plant protection. Increase the supply to agriculture of chemical additives and preservatives of feed, growth stimulants and biological means of plant protection, various types of film, polymeric materials and other types of chemical products. Increase industries with high-performance machine complexes, specialized cargo loading facilities.

Agrotechnical requirements for the machine and its working bodies

The industry produces mineral fertilizers in the form of granules with a size of 1... 5 mm, crystals, powders or in liquid form (nitrogen). The main technological properties of mineral fertilizers are density, granule sizes, looseness, humidity, friction coefficient, sliding on various materials, critical speed. The density of mineral fertilizers ranges widely from 0.62.0 t/m3, but the main types of fertilizers have very close values ​ ​ of this indicator: superphosphate - 11.2 t/m3, ammonium nitrate - 0.81.0 t/m3, potassium chloride and potassium salts - 0.91.0 t/m3. For fresh loose manure with density of 0.30.4 t/m3. The dimensions of the pellets typically range from 1 to 4 mm. As the dimensions increase above 4 mm, the strength of the pellets decreases, which leads to their destruction and deterioration of seeding.

The bulk of fertilizers is the ability to pass through holes. This property depends primarily on the humidity of tuks. Indirectly, bulk can be characterized by an angle of natural slope up to 35 °, and granulated up to 40 ° freely wakes up through the hole.

Hydroscopicity - the ability of fertilizers to absorb moisture from the air. It is estimated from 20 ballroom systems. The higher the score, the higher the hydroscopicity. Fertilizer humidity is the ratio of the mass of moisture contained in the fertilizer to the mass of the fertilizer itself, expressed in percent. The coefficient of friction of particles ranges from 0.47 to 0.6 - about steel, 0.5... 0.58 - about wood.

Analysis of existing machines or working bodies of similar purpose

Transporting machines are widely used in c/x for inter-mill fodder, grain storage and others inside aggregate movements of bulk and lump cargoes.

The main advantage of these machines: loads move without stops during loading and unloading, the combination of working and idling movements of the load-carrying element ensures the continuity of cargo flow.

The productivity of transporting machines is due to the high lift, strength and durability in operation. In order to ensure the main cargo flows, general-purpose transporting machines are used: tape, scraper, bucket, screw, pneumatic; and special-purpose conveyors: grain loaders, beet loaders, manure loaders, feed distributors and others.

In c/x belt conveyors are used: in warehouses, mills, grain currents. With large grain currents - loading and transshipment for the purpose of technological processing of grain, on loading of corn cobs, root crops, building materials and other cargoes. On belt conveyors, the load is less injured, which is especially important when transporting seed material.

Product processing plants use bucket elevators:

stationary - on elevators and mills for grain transportation;

portable - for periodic maintenance of technological processes in livestock farms.

Scraper conveyors are common in c/x on the principle of drawing: they move the load using moving scrapers along a fixed trough or pipe. These conveyors are used to transport well-loose cargoes: grains, fertilizers, as well as for manure harvesting in livestock farms. The advantage of scraper conveyors: simplicity of construction, loading and unloading anywhere. Disadvantages: crushing and erasing of the load during transportation and rapid wear of the guide chute. On plate conveyors, the load is carried on strips and flooring. In these conveyors, the traction member is simultaneously and load-carrying.

Justification and selection of new design

The mechanization of loading and unloading works contributes to the reduction of the cost of production and is important in reducing the agrotechnical time for sowing and cleaning.

The All-Union Research Institute of Mechanical Engineering together with design organizations create promising machines for loading grain and mineral fertilizers. Much attention is paid to mechanization and automation of production.

Thus, much is being solved in the design and manufacture of certain machines and devices. Take the screw conveyor. Screw conveyors are widespread in the form of stationary and mobile machines.

Screws are used to perform various technological operations: etching grain, mixing and distributing feed. The design of the screws allows you to transport poisonous, spiky other weights, load anywhere along the length of the conveyor.

Screw conveyor consists of loading device, transporting part and unloading device.

Screw - main working element; casing, support bearings and other elements - auxiliary. Depending on the type of material to be moved and the purpose, the screw happens: continuous - for bulk materials and liquid cargoes; tape - for large-piece and sticking cargoes; vane - for strongly adhering and fibrous weights and their active movement in flexible pipelines.

Screws are distinguished by the direction of winding and by the number of entries. The direction of winding is due to the kinematics of the machine, and the number of calls is due to the type of cargo. The weight in the conveyor casing moves according to the drawing principle under the action of the centerline, that is, the axial force of the screw. Weight is kept from rotation together with screw by gravity and friction between weight and casing. During vertical transportation, the load moves as a result of the difference in angular speeds of the load and the screw. The weight rotates under the action of centrifugal forces, and is braked by friction forces against the surface of the casing. In screw conveyor material moves independently from physical and mechanical properties of load, position of geometric and kinematic parameters of conveyor. However, the trajectory of the particles is different and depends on the speed of the screw.

In this design, the operation of the screw conveyor consists of two inextricably connected and coordinated main processes: loading and transportation.

The loading device determines the quantitative and qualitative parameters of the conveyor, where there is a complex interaction between the screw and the material. Thus, part of the screw in the charging device is a complex rotating structure (shutter) and creates a braking effect on the flow path of the load coming from the loading bin. Therefore, special feeders are installed in high-speed screws to improve loading. It is recommended to take the length of the turns in the loading part of the screw equal to l = (1.5... 2.0) p.

To better take the load and reduce initial resistances, screws are made with a gradually increasing pitch.

The conveying part of the screw consists of a screw. Transportation process consists in continuous action of screw surface on material to be moved.

The main parameter is the speed of axial movement of the load, which depends on the speed of rotation of the screw and other factors.

The casing of horizontal screws is open, and at steeply inclined and vertical ones it is made in the form of a pipe.

In our design, the inclination and height of the conveyor are adjusted with the help of rods that connect the conveyor to the wheels. The system of machines for complex mechanization provides for the creation of mobile, portable conveyors, warehouses and elevators .