Foundry technology

Contents

Introduction

1. Part Design Analysis and Casting Method Selection

1.1 Technical requirements for casting "Lower support"

1.2 Characteristics of SCh alloy

1.3 Selection of the casting process depending on the volume, nature and conditions of production

1.4 Definition of casting complexity group, casting dimensional accuracy and model set accuracy class

2. Select the location and number of castings in the mold

2.1 Definition of mold casting position and model and mold parting surface position during molding and casting

2.2 Definition of surface boundaries of casting made by rods

2.3 Selection and purpose of construction of signs, rods, slopes of rod signs and gaps

3. Runner and Runner System Selection and Calculation

4. Calculation and assignment of machining allowances and process allowances

4.1 Purpose of machining allowances

4.2 Purpose of process allowances

5. Casting Tooling Selection and Design

5.1 Calculation and selection of casting supports

5.2 Selection of model plates

5.3 Design and Material Selection of Models

5.4 Design of rod box and selection of material for its manufacture

6. Selection and description of manufacturing process for casting

6.1 Mold Manufacturing Technology

6.2 Assembly and control of shapes

6.3 Calculation of cargo weight

6.4 Charge composition

6.5 Purpose of alloy pouring temperature, mold casting holding time and casting pouring temperature, selection of ladle for pouring

7. Selection and description of manufacturing processes of moulding and rod mixes and paints

7.1 Selection of moulding mixture, state of moulds, characteristics of mixture, special additives, preparation and regeneration of mixture, equipment

7.2 Selection of rod mixture, physical and mechanical properties, equipment for preparation

7.3 Selection of anti-stick paint and preparation method

Bibliography

Introduction

The foundry provides castings - blanks intended for subsequent processing, parts of various branches of mechanical engineering: machine tool, automotive, energy, agricultural.

Casting in sand, metal, ceramic, graphite molds, injection molding and other methods are used to make castings. The main part, about 80% of all castings, is made in sandy forms. Foundry is a complex set of technological processes. The main ones are preparation of moulding mixtures, manufacture of tooling, moulds and rods, preparation of molten metal, casting of molds and quality control of castings.

In the plans for further development of foundry, much attention is removed to reducing the material capacity and labor intensity of casting, saving fuel and energy resources, and using low-waste and waste-free technologies. Many enterprises have experience in managing different production wastes. New technological processes are being introduced into the production, among which one can distinguish the technology of producing rods with curing with gaseous catalysts, obtaining large castings of high accuracy according to gasified casting models in dry stacking molds, vacuum film molding.

Controlled casting plants, manipulators for installing rods in molds, removing and interoperative movement of castings, multi-purpose robotic complexes and other mechanization tools are created. Work is underway to improve the mechanization and automation of finishing operations.

Various molding materials are used in the production of castings: sands, clays, binders and charge materials: metal, ferroalloys, etc. Molding materials and charge materials affect the properties of molds and rods, the metal to be prepared and, ultimately, the quality of casting. All this predetermines the variety of methods and techniques for controlling materials and works in the foundry, which are carried out by the supervisors of the foundry.

In order to improve the quality of products at the enterprise, in one to two years, internal quality certification is carried out. To increase reliability of casting equipment, it is envisaged to create structures according to the block-modular principle on the basis of spent bonds and units.

It is planned to equip 60-70% of the main units with built-in microprocessor equipment, automatic lines and complexes, provide diagnostic and automatic troubleshooting systems, as well as software control.

The experience of a number of advanced enterprises successfully carrying out technological re-equipment of foundry production shows that it is possible to achieve a significant increase in labor productivity and fundamentally improve its conditions only through the wide use of the results of the scientific and technical process.

The most common method (up to 80%) is casting into single sand molds, which make it possible to obtain castings from any casting alloys, small and very large, in individual and mass production with a high degree of mechanization.

When choosing the method of casting, it is necessary to proceed from the purpose of casting, economic expediency and take into account the following factors:

- configuration complexity and casting weight: casting "Lower support" of medium complexity;

- Serial production: large-scale;

- surface accuracy and cleanliness: casting must meet the requirements of GOST 2664585;

- grade of alloy used for casting: gray cast iron CH 18 GOST 141285.