Modernization of TsNSG pump 60-198

Contents

Introduction

1. Setting the task

2. Select Evaluation Criteria

3. Find technical information and select a prototype

4. Engineering analysis of initial data and refinement of the design task.. 125. Engineering Solution Search

6. Modeling

6.1Constructive calculation

6.2 Hydraulic calculation

6.3 Calculation of key connection for crushing

6.4 Calculation of threaded connection per cut

7. Development of design documentation

Conclusion

Introduction

Machine design is a creative process with its inherent laws of construction and development. The main features of this process are the multivariability of the decision, the need to coordinate the decisions made with the general and specific requirements for the structures, as well as with the requirements of the relevant GOST regulating terms, definitions, conventions, measurement system, calculation methods, etc.

Parts, assemblies, machines are manufactured according to drawings made on the basis of projects - a set of calculations, graphic materials and explanations to them, designed to substantiate and determine structural parameters (kinematic, dynamic, geometric, etc.), its productivity, economic efficiency. For especially critical constructs, the project is supplemented with a layout or an active model.

1.Resetting a Task

Analysis of main faults and causes of failures of multistage centrifugal pumps was carried out on the basis of data taken in JSC Uchalinsky GOK and expert assessments of mechanics serving pump units.

A survey of experts showed that the main reasons affecting the failure of the pumps are wear of the unloading rings, which leads to a failure of the slot seals and a decrease in pump productivity. Wear of bearings and wear of seat sockets in brackets increases vibration of the pump, which leads to their premature failure. Abrasion of the working surfaces of the shaft jacket and rotor nut makes it impossible to provide the necessary tightness of the pump. If the rotor nut can be replaced during SPR, then the shaft jacket can only be changed during overhaul, which also affects the life of the pump.

Experience in the operation of multi-stage centrifugal pumps of the CNS type, especially when they pump out contaminated mine water with abrasive particles, shows that the replacement of discharge rings and hydropaths has to be carried out once a month.

Based on the analysis of the operation, it can be concluded that rapidly worn parts of multi-stage pumps of the CNS type, affecting the total operating time of the pumps before failure, are: rotor parts, elements of the unloading device and bearing units. Namely: the hydropyat ring; unloading rings; shaft shirt; rotor nut; gland bushing; bearings; rear bracket; front bracket.

Based on the structural and functional analysis performed,

the basic principle of the design task is formulated:

- perform modernization of centrifugal pump, parts of which would have high wear resistance and simple design.

Select Evaluation Criteria

The selection of the main evaluation criteria (technical and economic), which in the future will be the main parameters of maintenance, follows from the requirements of the basic principle of the design task, these are:

1. Reduction of wear of centrifugal section pump elements, reduction of pump maintenance costs, as well as increase of overhaul period.

2. The cost price should not exceed 10 thousand rubles.

3. Possibility to carry out modernization in-house of boiler area. This will eliminate the financial costs of attracting contracting organizations and reduce the time for reconstruction.

Engineering Input Analysis and Engineering Task Clarification

As a tool for engineering analysis, structural and functional analysis of the design of the unloading device of the patent RU2165038 C2 proposed in the prototype was used. To perform its functional purpose, the centrifugal pump unloading device will consist of the following parts: a unloading disk, a ring-holder, a unloading ring, which will be assembled as one element of the centrifugal pump is a hydropyat.

As a result of the analysis, a clarification of the basic principle of the design task was formulated, which was that in order to create the design of the discharge device of the centrifugal pump, which would have high wear resistance and simplicity, it was necessary to change the design of the device itself.

The evaluation of the results of the stage showed the availability of a sufficient amount of initial information for the search for a technical solution for the design task.

Modeling

The first stage of modeling is the abstract model of a technical solution, which I have already discussed at the stage of finding a technical solution.

At the second stage - theoretical modeling, the following preliminary calculations were carried out:

Development of design documentation

Considering that the pump is intended for in-plant use, the terms of reference for its design were developed in a simplified form and approved by the chief engineer of the enterprise. After the development of the draft drawings, the general layout of the pump and the structural diagrams of its main parts, at the stage of finding a technical solution for the design task, it was decided that due to the average level of complexity created by the maintenance, as well as in order to reduce the design time, it is advisable to immediately begin the development of detailed documentation.

The following were used as basic initial information for development of working drawings of centrifugal pump units and parts:

- technical assignment (TA) for design of centrifugal pump.

- sketched drawings made during technical solution search,

- calculations performed at the stage of theoretical modeling.

Conclusion

Modernization of centrifugal pump CNS 60198 was considered in this course work. The task for the course work is to upgrade the pump. The purpose of modernization of this unit is high wear resistance of parts and simple design.

The objectives of the work are as follows:

- unloading device is designed;

- materials were selected for modernization parts;

- strength calculations were made;

This modernization made it possible to increase the operability, increase the service life of the pump, increase its reliability and durability. Accordingly, the frequency of pump repairs will decrease, which is a great advantage from the point of view of the feasibility study of modernization. Thus, this modernization has shown its feasibility in application at the design level, and in the future may find its application at production facilities.

модернизированный ЦНСГ 60-198R03.cdw

Спецификация общего вида_V5.11_R03.cdw