Development of the process of restoring the crankshaft of the ZIL-130 car engine

Contents

CONTENTS

Introduction

1. Characteristics of crankshaft operating conditions and list

possible defects

2. Technical conditions for defects and methods of determining defects

3. Possible routes of crankshaft recovery\\\\\

4. Analysis of ways to repair defects included in the route,

choosing rational ways

5.Base the route recovery and development route

maps

6. Calculation of process operation modes and

Technical time standards

7. Calculation of Recovery Production Program

crankshaft

8. Determination of equipment quantity and area

production room for technological implementation

crankshaft recovery process

9. Evaluation of crankshaft repairability

10. Justification of work organization and planning solution

11. Health and Safety Measures

12. Technical and economic indicators of developed technology

Conclusion

List of sources used

Introduction

During operation, the vehicle is subject to various factors that have a significant impact on the technical condition of the main units, assemblies and individual parts. So, first of all, other materials, rubber parts, AKB plates and plastic components change their operational properties under the influence of aging. Significant damage is caused by the effect of corrosion on all unprotected metal surfaces. Its impact is so noticeable that when developing protection methods, corrosion fatigue, corrosion cracking, and corrosion-mechanical wear are specially distinguished. According to statistics, the most common reason for the need to replace a particular part is mechanical wear. Wearing out, the mating parts begin to interact with deviations from the initial adjustments, this leads to even more intense wear of the contacting surfaces. Metal fatigue significantly, albeit to a lesser extent, affects the resource for the use of parts and assemblies of special equipment. Fatigue wear results in dyeing. For example, it is often observed that the babbit layer is painted on the inserts of the bearings of the connecting rods and the crankshaft, metal is painted on the treadmills of the separators, on the profiles of the gear teeth. But the impact of metal fatigue can be reduced. It is noted that the cause of this phenomenon most often lies in improper, careless assembly or in violation of operating rules. Another consequence of violation of operating standards is warping of parts. When warping in "injured" parts, for example in the heads of motor blocks, structural changes and large internal stresses occur. Mechanical damages, cracks, holes, balls, as well as dents and twists are observed in the most loaded places of the frames, in the body parts of various mechanisms. Cracks can appear in radiators, in block heads, as well as on block walls, for example, when cooling liquid freezes. As a result of these and other similar numerous factors, it is necessary to replace the part. Along with the installation of new spare parts, worldwide there are growing trends in organizing the restoration of the operability of worn-out parts by various methods.

The purpose of this course project is to develop the process of restoring the crankshaft of the ZIL 130 engine using the most advanced forms and methods of organizing repair production.

Crankshaft recovery routes

In course design, the development of part recovery processes is carried out according to route technology, which contributes to the rational use of equipment, saving energy resources and eliminating counter flows of parts moving through production areas of the repair enterprise.

Routing refers to a technology composed of a complex of defects, and the route is the sequence of process operations with the shortest movement of the part through workshops and sections.

When developing recovery routes for parts, follow the following principles:

- the combination of defects in each route must be valid and based on the results of the investigation of the patterns of defects in this part;

- the route shall provide technological relationship of combinations of defects with recovery methods;

The number of repair routes for the part must be minimal.

- restoration of parts according to route technology should be economically feasible and take into account the technological need and the possibility of restoring individual surfaces.

Parts with defects that do not fit into the main routes are sent along a rare route. A route list is drawn up for each route.

The combination of crankshaft defects allows their restoration along three routes.

Crankshaft recovery route No. 1:

- roll fragments and cracks - reject;

- wear of key slots - brew;

- radial run-out of neck under pulley hub and gear - brew;

Crankshaft recovery route No. 2:

- wear of hole in flange for bearing - install bushing;

- wear of neck for pulley and gear - surfacing;

- wear of connecting rod necks;

- wear and tear of the main necks;

Crankshaft recovery route No. 3:

- increase the length of the anterior root neck, balls or hairlines on the thrust surface - treat the thrust surface until the balls and hairlines are eliminated;

- shaft bending - to rule;

- wear of connecting rod necks - process to repair size;

- wear of the main necks - to be treated to the repair size;

In this course project, the technology for restoring the crankshaft along route No. 2 will be developed.

Analyze how to repair defects in the route

When choosing a more rational method of restoring a part, a number of initial data are taken into account: the dimensions, shape and accuracy of the production of the part, its material, heat treatment, working conditions, the type and nature of defects, the production capabilities of the repair plant and others. The optimal method of reduction is selected according to the following criteria: applicability, durability, economic and techno-economic, considering them in the specified sequence.

1) Wear of bearing flange hole

This wear occurs due to oxidation, abrasive, friction, dry sliding, variable loads. Eliminated by several methods: electric arc manual welding, ironing, gas manual welding, vibration surfacing, inserts of additional repair part, namely bushings. First there is bore of lathe hole in flange for bushing pressing, then bushing pressing and at the end of bore hole for bearing. This process is a simple process and the recovery equipment used, as opposed to the others. The only disadvantage is the reduction of the strength function of the part. But in this case, this will be insignificant.

2) Neck wear for pulley and gear

This malfunction is manifested due to friction, sliding, variable loads. One commonly used method of restoring the crankshafts is grinding. Advantages of this method in its technological simplicity. The equipment requires a round grinder and a typical tooling. But this method also has a number of drawbacks. Loss of interchangeability of parts, the need for parts with repair dimensions, the presence of storage areas for them.

In addition to restoring wear of the support necks for repair size, widespread use is found: surfacing under a layer of flux, vibration surfacing, chrome plating, ironing. By analyzing possible recovery methods and their techno-economic characteristics, we have come to the opinion that the most acceptable and effective in terms of economic, technological and other factors is vibration-based surfacing.

3) Wear of connecting rod necks

This malfunction is caused by friction, oxidation, abrasive. Addressed in several ways. Flammable spraying. By spraying in the medium of carbon dioxide. But the cheapest and fastest method is to treat the surface to repair dimensions by grinding.

4) Wear of the root necks .

This failure is similar in all parameters to the wear of the connecting rod necks. And it will also be eliminated by grinding to repair dimensions .

Conclusion

During the course design, the process of restoring the crankshaft of the ZIL130 engine corresponding to the chosen route No. 2 was developed.

Some of the most common defects encountered during operation:

- wear and tear necks;

- wear of hole in flange for bearing.

According to these defects, a map was developed, a room was designed, economic indicators were calculated.

During the development of this exchange rate, it was calculated

The recovery technology includes:

Selection of process equipment;

Process rationing of operations;

Equipment calculation and selection;

Calculation of the production area.

The project describes the main measures for labor protection and sets out the most important rules for the safety of workplace behavior.