Design design of the ME-130 spinning top with a capacity of 500 kg h

Contents

Job for Course Project

Introduction

1 Status of the question

2 Description of design and operation of the designed wolf

Appointment

Construction Description

Description of operation

Process characteristic

3. Calculations

Process calculation

Kinematic calculation

Calculation of V-belt transmission

Safety precautions

Environmental protection

List of literature used

Introduction

In our country, the industry produces a large number of machines for grinding meat. Milling of meat and meat products is one of the main important technological processes widely used in the technology of sausage products, meat semi-products, canned food and other products.

By grinding is meant the process of separating the material into parts under the influence of mechanical forces. As such, grinding is a process of forming a new surface by a cutting tool to give the material a predetermined shape, dimensions and surface quality. Grinding is carried out by various methods: cutting, sawing, crushing, splitting, breaking, abrasion, impact or their combination. Of the known methods for grinding meat and meat products, cutting and sawing are most widely used.

Priority in the study of the process of cutting meat and meat products belongs to A.I. Peleev. For the first time, he proposed the classification of meat cutting machines, typification of cutting tools and empirical formulas for determining cutting forces. The cutting theory was further developed in the works of scientists Ivashov V.I., Klimenko M.N., Bakunets G.V., Yurkov S.G. and others.

The design of the working elements of machines for fine grinding of meat products by cutting depends on the required degree of grinding, the kind and structure of the milled products, the flow capacity, etc.

The crushing mechanism of the wolf is conical, cylindrical and flat. The latter was most widespread. This is due not only to the convenience and speed of maintenance, but also to the possibility of performing stepwise grinding on it, as well as to the simplicity of manufacture and reliability of operation. It is a series of fixed grids and rotating knives.

The most common is the grinding mechanism, which stands from the receiving, intermediate and outlet grids, two-sided and one-sided multiple knives. A feature of the grille type tool design is the shape and dimensions of the holes, which are circular cutting edges. The diameter of the holes determines the flow rate of the raw material and the degree of its grinding. The shape of the holes is round, square, oval, bean-shaped, with and without bevels, etc. Knives for wolves are used mainly three- and four-toothed, solid and composite, with one-sided and two-sided sharpening, with rectilinear and curvilinear cutting edges. For meat veneering during grinding, vein knives are used in front of the output grating of the wolf. They have special grooves spaced apart along the teeth, along which, when crushed, they are removed from the cutting zone of the film and tendon. Other structures of vein knives are also known.

The process of effluent of raw material through the holes of the grating is considered in the theory of cutting as a process of grinding with a punch, where the cutting tool is the fixed grating itself, and its cutting faces are its holes with a sharpening angle of 900. And the process of cutting the raw material at the outlet of the grid holes with a rotating knife, which is a cross-shaped shape with rectilinear faces, is considered as a process of cutting with a blade.

According to the cutting theory, the cutting of materials having elastic-plastic properties, such as meat, by the blade of a knife, is as follows. At the beginning of the movement of the knife relative to the material, it is gradually wedged into the material without disturbing the integrity and simultaneously compressed in the direct contact zone, subjecting the latter to deformation. This occurs until the material has fully exhibited its elastic deformation properties, reaching maximum values. Further, at the moment when the specific pressure in the contact zone reaches more than the value of the ultimate strength of the material, its destruction (cutting) occurs along the line of the greatest stresses arising between the blade of the knife and the material.

The cutting of such materials is characterized by the presence of two zones - the deformation zone and the cutting zone. At the same time, the cutting process is accompanied by simultaneously overcoming the elastic-plastic properties of the material, friction between the contacting surfaces of the cutting tool and the material, an increase in temperature in the contact zone and other phenomena.

The following factors have a significant influence on the process of grinding meat and meat products: raw materials (its structure and physical and mechanical properties), a cutting mechanism (diameter of grid holes, completeness, degree of flooding, etc.), design parameters (type of supply, design of the screw and working cylinder, etc.), kinematic parameters (speed of knives, speed of raw materials supply) and operating conditions.

The capacity of the rod is determined by the throughput of the cutting mechanism, which in turn depends on its design, completeness, sharpening and tightening.

At present, wolves have become widespread, which, along with grinding, perform other technological operations - mixing, vein, ambassador, stuffing shells in the production of sausage products. For their implementation, parts are mounted in the receiving hopper, which simultaneously mix and pump the raw material into the grinding mechanism; additional nozzles for filling sausage shells are installed on the wolf neck.

Wolves used in the meat industry are subject to the following requirements:

They shall be suitable for grinding any product with varying degrees of grinding;

Cutting, if not required by special process conditions, such as in the grinding of glue-gelatin or other raw materials, should not be accompanied by large compressive forces, which can lead to the separation of a liquid fraction from the processed product;

The purpose of the project is to develop a wolf design with a capacity of 1000 kg/h.