Selection of equipment for concrete mixing station

 

1. principle of general selection

(1) production scale

The production capacity of concrete mixing equipment is judged according to the size of the production scale. The annual output of less than 200 thousand M3, generally not less than 90m3 / h concrete mixing equipment productivity; the annual output of 20 m3 in case 300 thousand, concrete mixing equipment productivity is 120m3 / h; the annual output is more than 300 thousand M3, concrete mixing equipment productivity is 150 m3 / h or 200m3 / H.

(2) construction site

According to the size of the construction site, concrete mixing building or concrete mixing station can be selected. The concrete mixing plant is selected to enhance the aggregate once. The productivity of the mixer with the same capacity is higher than that of the mixing plant. The overall shape is neat and beautiful, and the plot area is small, the production environment is good, but the manufacturing and installation cycle is long, and the one-time investment cost is high. For concrete mixing station, aggregate needs two lifting, flexible layout, short manufacturing and installation period and low one-time investment cost, but the material area is large and the production environment is poor.

(3) attachment device

To select the specification and size of the concrete mixer according to the assigned work equipment. The loading capacity of the mixer should be matched with the feeding capacity of the mixer, and the mismatch will affect the working efficiency. The loading capacity of the loader should be matched with the height of the feeding station of the concrete mixing station.

(4) management function

If the intensive network management is adopted, the network management function of concrete mixing equipment should be considered to avoid difficulties in the future upgrade.

(5) equipment technical performance

It is mainly considered from the aspects of the advanced, reliability, good and versatility of the equipment. The equipment should have the characteristics of advanced working principle, high degree of automation, powerful management function and good environmental protection performance. The equipment should be equipped with excellent configuration, reliable control mode, strong applicability and good maintenance performance. In addition, the high precision of measurement, good mixing quality, high production efficiency, low energy consumption, large use of standard parts and good interchangeability are also considered.

(6) supplier reputation

It mainly includes whether the installation and commissioning are strict, the technical guidance and training are in place, the after-sale service is timely, and the spare parts supply is full.

(7) performance and price ratio

It is unwise to pursue equipment and technology performance in an all-round way. It will increase meaningless investment. But pursuing low investment and reducing the technical performance of equipment will increase the cost of use. Such a practice is also not advisable. At present, the comprehensive performance of imported equipment on the domestic market is high, but the price is also more expensive. Several well-known brands of domestic equipment, though the comprehensive performance is not comparable with the imported equipment, but the key parts are widely imported components. The main performance is not much worse than the imported equipment, but the price is much lower. It is more reasonable to choose the appropriate ratio of performance and price.

 

The selection principle of 2. key components

(1) the mixer of the commercial concrete mixing equipment

The forced mixer has good mixing quality, strong overload capacity, no segregation of discharge, high production efficiency, and can adapt to various properties of concrete mixing. At present, the forced mixer is widely used in commercial concrete mixing plant. But its structure is more complex and its use cost is high. Compulsory mixer consists of twin shaft, single horizontal shaft, vertical shaft and planetary forms, twin shaft mixer mixing due to good performance, high production efficiency, good adaptability, structure characteristics, good reliability, is suitable for the production of concrete; the single horizontal shaft mixer and single shaft mixer because of its structural features and adaptability. In the concrete mixing equipment has been used less: planetary mixer used at present is not common in imported equipment.

(2) electronic control system of commercial concrete mixing equipment

At present, there are various forms of electronic control system in domestic concrete mixing station, mainly based on the following 3 kinds of control methods.

(1) distributed microcomputer control: this type of control is widely used in the design of early mixing station. The core of the control system is a programmable controller. The first level computer is used only as a management report. The function and function of the computer is not very obvious. With the wide application of commercial concrete, the functional requirements of concrete mixing station are more and more complex, and the application of this control form is very difficult.

The microcomputer control and centralized control form: the computer control and management functions in a computer, the task is relatively heavy, the synchronization of data and statistics does not report the production process, not any statistical data, the measurement of artificial interference too much. For example, the compiling of the metering control program, the precision of the signal amplifier and the A / D board, will affect the measurement accuracy.

The centralized control of dual microcomputer: this form is to solve the man-made interference measurement aspect. The special ingredients and control instruments, production control and management functions on two computers, do not interfere with each other, the production control and report statistics, synchronization, and management of computer production can also be used as a backup machine provides a network interface and a computer.

 

3. principles for the selection of other devices

(1) aggregate system

As the material of the silo is affected by the auxiliary equipment and the site, the volume of the silo should be selected.

For a mixing station, the volume of a single bin is generally greater than 20m3. If the belt conveyor is used or the concrete storehouse can be larger, it will reduce the area of the stockyard. The volume of a single storehouse in a mixing building is generally greater than 50m3. Generally, the concrete mixing plant is made up of batching stations. There are two structural forms. The all steel structure proportioning station adopts the ground ingredients, which is easy to maintain, and easy to drain.