Development of a hammer crusher for grain grinding

Contents

CONTENTS

Introduction

1 Rationale of the course project theme

2 Process of feedstuff production

2.1 Process operations and requirements for their execution

3 Overview of crusher structures

4 Design part calculation and description

4.1 Calculation of hammer crusher parameters

4.2 Shaft strength calculation (updated)

4.3 Crusher housing calculation

4.3 Calculation of crusher drive

5 Safety requirements during operation

Conclusion

List of sources used

Paper

Course project: 31 pages, 9 drawings.

Keywords: crusher, process, shaft, drive, housing.

The purpose of the course project is to develop a hammer crusher for grinding grain.

In the course project, a hammer crusher was developed for grinding grain. A description of the process of feedstuff production, an overview of the crusher structures is given, as well as the main elements of the apparatus (housing, drive, shaft) are calculated, which is reflected in the design and graphic parts of the course design.

Introduction

The main tasks facing the food industry are ensuring the sustainable supply of quality food products to the population and organizing the production of fundamentally new types of products, as well as the creation and introduction of modern high-efficiency types of technological equipment, which, based on the use of advanced technologies, increase productivity, reduce the negative impact on the environment and contribute to the savings of raw materials and material resources.

One of the main tasks in the development of the processing industry is to increase its efficiency. Of particular importance is the introduction of progressive technological processes for the processing of products and improved technological means, and on the basis of their in-line technological lines for the preparation of various products. One of the most important machines in the processing industry is a crusher.

Hammer crusher - a mechanical crushing machine used to destroy pieces, grains and particles of mineral raw materials and similar materials, by crushing rock with hammer blows hinged to a rapidly rotating rotor, as well as by the method of crushing pieces when hitting the crusher body plates.

Hammer crushers can be divided into: single-rotor non-reversible hammer crushers with grates, single-rotor non-reversible hammer crushers without grilles, two-rotor hammer crushers with grilles, two-rotor reverse crushers with grilles, two-rotor reversible crushers with grilles.

There are also crushers of large (up to 100-300 mm), medium (25-100 mm) and small (5-25 mm) crushing .

Rationale for the topic

Combined food is a mixture crushed to the necessary size of fodder products, compiled according to scientifically sound recipes and correctly balanced in terms of nutrients, minerals and vitamins.

Feeding poultry and farm animals with compound feed is much more effective than feeding them one or another feed in turn, since they do not contain all the nutrients necessary for the animal's body. For example, most cereals are rich in starch, but poor in protein. Therefore, for animals to get the necessary amount of protein, they are fed a large amount of grain, which not only leads to its irrational use, but also can disrupt the metabolism and reduce the productivity of livestock.

The mixture of grain raw materials with other high protein products is much more effective, since in it protein and starch are in a ratio more favorable for the body of the animal. The value of such a mixture can be increased by introducing a small amount of biologically active substances into it - vitamins, salts, trace elements, antibiotics, etc.

When feeding compound feed, the productivity of animals, the type, fur animals and fish, significantly increases. Young animals grow faster and develop better, its viability increases. With uniform nutrition, when one type of food prevails in the daily diet, productivity decreases, young people lag behind in growth and development, and the incidence increases.

Thus, the use of feed feedstuffs balanced in the main elements has a number of advantages: it saves feed resources, including feed grain, as the consumption of feed per unit of production decreases; provides the opportunity to make the most rational use of waste generated in various industries - food, flour crumbs, meat and dairy, fish processing, etc. Feedstocks may include raw materials that are not separately used for feeding due to poor appearance, odor, structure, etc.; combined feed can be given a shape convenient for feeding, mechanization of the feed distribution process.

For the production of feedstuffs, a feedstuff industry has been created in our country, in recent years the production of feedstuffs has been developing directly in farms. This makes it possible to more fully and rationally use the available raw materials, reduce the costs of their transportation, reduce the cost and reduce product losses.

The feed industry produces several types of products that are either ready-to-eat fodder or an integral part for the further preparation of feed fodders or feed diets, namely, full-diet feed, concentrate feed, protein-vitamin additives (BVD), feed mixtures, premixes, carbamide concentrate, whole milk substitute (ZCM).

Combined feed is produced for almost all types of productive farm animals, as well as for feeding reindeer and sheep kept on spur pastures. According to the physical structure, compound feed is divided into granular, briquetted, loose, grits, crumbs; for fodder value - for full-breed and combined feed-concentrates.

Full-diet feedstuffs fully provide the need for animals and nutrients and biologically active substances, when they are used, other feedstuffs are not required. These feedstuffs are produced primarily for birds.

Feed-concentrates have an increased content of protein, minerals and micro-additives. They are fed to animals in a limited amount as an addition to cereals, coarse and juicy

fodder, for greater provision of biologically full feeding. These feedstuffs are intended for cattle, pigs, rabbits and other animals.

Fodder mixtures are a homogeneous product consisting of fodder products used in feeding animals, but not containing a complete set of nutrients. They are made mainly for cattle in special installations of large plants from by-products of cereal production (louse, flour) with the addition of molasses, carbamide, chalk, salt and other additives.

Protein-vitamin additives are a homogeneous mixture of high-protein and mineral fodder products and micro-additives crushed to the required size. The use of HBV directly for feeding animals is categorically prohibited both for economic reasons and because of the direct harm that can be done to animals eating combination food with a very high protein content (up to 30... 40%). They are used in agricultural enterprises for the production of compound feed based on fodder grains, herbal vitamin flour and other feed products .

2 Process of feedstuff production

Dry feed mixtures include loose and granular feed for animals and birds of all production-age groups, full-breeding granules and briquettes for cattle and sheep. This group also includes various concentrates and multicomponent additives in the feed mixtures to be prepared. The technological processes of their preparation are similar in content and sequence of the main technological operations: preparation of raw materials, grinding and accumulation, dosing, mixing and compaction into granules or briquettes.

Combined feed includes mixtures of crushed grain components with protein-vitamin-mineral additives (BWMD), that is, full-diet feed mixtures balanced in nutrients, protein, vitamins and trace elements in accordance with the physiological needs of animals and birds of production-age groups. Depending on the purpose, protein and vitamin-rich components include protein and vitamins: extraction cake, fish, meat and herbal flour, yeast and mineral feed - chalk, salt, etc. They are part of the BMD or special additives are separately introduced - premixes, representing mixtures of biologically active substances - trace elements, antibiotics, hormones, medicinal preparations, etc., with filler (crushed corn, bran, extraction cake).

The main components of compound feed are grain feed: corn, barley, oats, wheat, millet, rye, sorghum and legumes (peas, vic, lentils, fodder beans, soybeans).

Cereal grains are characterized by a high starch content (up to 70%), protein content 10-25%, fat - up to 15%. The grain of legume proteins contains 2-3 times more, so it is recommended to prepare feed from grain mixtures so that cereals are 60-65%, and legumes 15-20%. In the composition of feedstuffs, grain mixture occupies 80-85%, the remaining 15-20% - PMD, including 1-2% of premix.

The greatest effect on the use of cereal and legume grains can be obtained by feeding them as part of balanced feed. At the same time, the consumption of feed per unit of contribution is almost halved. This is especially noticeable in poultry farming.

Feedstuffs are prepared at state and inter-farm feedstuffs and partially in farm feedstuffs according to the recipes approved by the relevant GOST and specifications, which are given in the special feedstuff handbooks. BVMD and premixes are prepared in specialized workshops of feed mills or at special enterprises. The general

requirements for feed: humidity not more than 14.5 - 15%, foreign impurities not more than: metal 10 - 25 mg/kg, sand 0.5%; PMD for collective farms and state farms - humidity not more than 14%, fraction size 3 mm not more than 10%, digestible protein not less than 25%, raw fiber not more than 8%, sand not more than 0.5%, metal inclusions not more than 25 mg/kg.

When herbal flour is included in the composition of PMD, it is allowed to increase fiber by 0.25% for each percentage of added flour, but in total not more than 11%.

Conclusion

As a result of the course project, the design of the crusher was reviewed. Various types of crushers are considered, as well as structures and principle of operation.

A separate section is devoted to the description of the process of producing feedstock, from the acceptance of raw materials to the packaging and storage of finished products.

Parameters, housing, crusher drive are calculated from the given initial data.

The safety of the hammer crusher is described in detail.

The graphic part shows: the assembly drawing of the hammer crusher and detailing.