Concrete pump SS-161

Contents

Introduction

Purpose, brief description of the device and operation of the machine

Analysis of the prior art in the field of machines of a given type. Research part of the project

Description of concrete pump structure and hydraulic diagram

Determination of main parameters of concrete pump

Concise design of concrete pump and justification of layout solutions

Development of safety, environmental, energy saving measures during concrete pump operation

Conclusion

List of literature used

Appendix A

Appendix B

Introduction

At the beginning of the 21st century, the construction complex is undergoing serious structural changes, which are accompanied by a sharp investment decline, a repeated decrease in the volume of construction and installation work, and a reduction in the production of the most important types of construction machines, equipment and materials. That is why improving the efficiency of road construction machines is the main task in their operation, which leads to an increase in labor productivity and the pace of construction.

Any construction machines shall provide the necessary productivity in the open air, in any weather, at any time of the year, often working in constrained conditions of the construction site. Therefore, a number of special requirements are imposed on the construction machine, and the more fully it meets them, the more suitable it is for use in construction production.

The set of requirements for the machine depends on its purpose and the modern state of science and technology. These requirements are divided into structural, technological, operational, economic and social.

Design requirements take into account the main technical and structural parameters of the machine, its general layout, strength and reliability.

In the process of designing the machine, the foundations of the technology for its manufacture are laid, as well as the requirements of mobility, maneuverability and cross-country ability of the machine are taken into account,

The processability of the design provides for the simplicity and convenience of manufacturing parts, assembling units and the machine as a whole, as well as reducing its cost. Repairability (repairability) of the machine provides for the convenience of replacing units and assemblies, unification and normalization of parts, and other issues of organizing aggregate repairs.

Social requirements and ergonomics are to ensure labor safety during operation of the machine, favorable working conditions of the driver, convenience of machine control and maintenance, automation of machine control processes, monitoring and accounting of its work.

In addition, the machine must meet the modern requirements of production aesthetics - to have beautiful external shapes, good finish and stable color.

Thus, when creating new construction machines or their fundamental modernization, the above requirements should be taken into account and provided:

- high technical and economic efficiency and productivity corresponding to advanced technology and organization of works;

- simple design, easy and safe maintenance;

- high working and transport speeds;

- universality and high quality of work;

- strength and reliability, ensuring long service life with minimum time, labor and means for maintenance and repair.

Development of safety, environmental, energy saving measures during machine operation

6.1 General safety requirements.

Construction machines operating for a long time in one place are installed on a solid foundation in such a way that they are provided with good access. Mobile construction machines are installed on liners that prevent their overturning or arbitrary movement during operation.

The most important condition for safe work on construction machines is the correct operation of the machines and regular care for them. Therefore, only drivers familiar with the design and device of this machine, safety rules for working on it and having a certificate of passing safety tests are allowed to work on the construction machine. Workers must submit a medical certificate of health. Outsiders are forbidden to be near the working machine.

Before starting the machine, you must carefully inspect it, check whether there are any foreign objects on it or inside it (tools, fasteners, etc.). After making sure that the machine is healthy, you can start working on it. If a defect is detected, the machine must be stopped and the fault resolved. Do not operate on a faulty and unregulated machine.

All transmission mechanisms shall be covered with protective casings. Cleaning, repair and lubrication of moving parts of the machine, as well as their attachment and regulation during the operation of the machine are strictly prohibited.

When servicing and repairing construction machines, you need to use only serviceable tools. Work on sandpipers, as well as chop metal only in protective glasses.

When working in the dark or at night, the workplace and machine shall be illuminated.

The electrical network must be well insulated. Housing of electric motors, rheostats, metal casings of starters shall be grounded. Installation and repair of earthing shall be performed at removed voltage. It is forbidden to repair and clean electric motors and start-up control equipment under voltage.

Electric motors, electrical equipment and electrical mains can only be repaired by persons entitled to perform these works. Before repairing, the motors must be disconnected from the mains and fuses removed.

Voltage of portable electric lamps must not be more than 36 V.

Each machine having an electric drive must be reliably grounded. There are two types of grounding electrodes: natural - metal pipelines, casing pipes, metal structures connected to the ground, and artificial - in the form of metal pipes clogged into the ground to a depth of 2.5-3 m with a diameter of 50 mm.

Personnel serving construction machines should not have clothes that can be captured by moving parts of the machine - the belts should not hang, the ends of the sleeves should be tightly pressed to the hands, etc. Hair must be removed under the headdress.

The mixer installed on the platform shall be enclosed on all sides.

Inspection and cleaning of the drum and ladle during machine operation is prohibited. Under the raised bucket of the skip lift can be located only if it is fixed on the hook. During unloading of the finished solution or concrete mixture, it is forbidden to help this with a shovel, scrap, etc.

After installation of concrete pumps, they are tested during operation on water for 30 minutes. Under pressure of 10-15 atm. During operation of concrete pumps do not tighten glands. It is forbidden to inspect and repair the air hood, the outlet nozzle and disconnect the concrete duct until the pressure in the air hood is reduced to atmospheric pressure. It is forbidden to blow the concrete duct if there is someone in the working area.

Do not use concrete pumps if safety valve and pressure gauge are faulty.

During operation of concrete pumps it is necessary to constantly monitor the pressure by the pressure gauge and immediately turn off the pump if the pressure exceeds the permissible one.

The nozzle tip can be cleaned only after the concrete duct pressure stops and when the valve on the nozzle or air duct is closed; it is recommended to cross the concrete duct 180 near the nozzle during cleaning.

During the operation of concrete pumps, it is impossible to abruptly bend or break the hoses of the concrete duct. When disconnecting individual joints of hoses or pipes, safety glasses must be put on.

Rubber hoses for transportation of mortar in places of passageways and passageways shall be covered by transition bridges.

Regular inspection of construction machines, constant supervision of their work and timely repair are measures that improve the safety of maintenance personnel on machines.

6.2 Environmental Protection

The main harmful production factors when working with a concrete pump are increased production noise, vibration, which has a negative impact on the environment.

The reduction of production noise can be carried out both by improving the design of machines and its assemblies, as well as by improving the technical operation of machines, timely repair of equipment, the use of sound absorbing (soft) linings, installation of casings, noise silencers. Significant reduction of production noise occurs when process control is automated, when equipment and maintenance personnel are located in various isolated rooms.

To protect against vibration, vibration insulation is used, which can be active and passive. Active vibration insulation aims to reduce oscillations of the foundation, on which equipment is installed, which is the source of oscillations or shocks. Vibration isolating gaskets are laid between foundation and machine.

In passive vibration isolation, vibration isolation platforms are used. At the same time, workers must have special anti-vibration clothing - boots and sleeves, in which soft large-porous rubber serves as an insulating material.

6.3 Energy saving.

The growth of electricity consumption in our country over the past decade has significantly exceeded the pace of commissioning of generating capacities. This led to the formation of a deficit in the reserve of free capacity in most regions of the Republic of Belarus. The problem of capacity shortages can be solved in two ways: either by increasing the pace of construction and commissioning of generating capacities, or by calculating the consumption of energy produced and introducing the latest energy-saving technologies.

One of the most effective ways to save energy in pump units operating with variable load is the use of an adjustable electric drive (REP). The analysis of the results of the use of a frequency-controlled drive (VSD) given in the work showed that in some cases it leads to tangible energy savings, in others it is insignificant, in third - the installation of the drive does not lead to savings. A study of the methods and forms of application of the adjustable drive indicates that in practice, the most often used are technically easiest, and the least cost-effective methods of controlling pump units, such as stabilizing the pressure at the pump outlet. The use of energy saving potential is not more than 1530%, which leads to the fact that most of it, even after the installation of the adjustable drive, remains unclaimed, despite the significant costs of its purchase, installation and adjustment.

Conclusion

In carrying out this course project, I received theoretical skills in the field of construction and principle of concrete pumps operation, and also got acquainted with the method of calculation of basic parameters of concrete pump, its design. The whole project was aimed at modernizing the already existing concrete pump SB161, which is currently produced by Russian enterprises .

In the course of this course project, a technical solution for improving the design of this pump was proposed and considered. The main measures to comply with safety and energy saving requirements are considered.

This course project consolidated the acquired knowledge in the field of supply of freshly prepared concrete mixture from specialized concrete vehicles to the place of laying.