WEM Automation

PLWC Series Automatic Micro Weighing Scale


1. Introduction


PLWC micro weighing scale is a product which has high requirement on mechatronics. The following are its main parameters:

1. Total ingredient weight per batch: 50-300Kg;

2. Dynamicproportioningprecision: 0.05%;

3. Staticproportioningprecision: 0.03%;

4. Singlebinproportioningprecision: Deviation≤20g;

5. Single batchproportioningtime:≤180s (i.e. proportioning speed 15 batch/hour)

6. Easy operation and stable system;

7. Ingredient data report is available and can be exported and printed out.


In the following part, we would illustrate from machine structure and controlling system.


A project site in Guangxi


This system has adopted the concept of the most advanced automatic control system in this industry. There is a scientific division between upper and lower computer. The upper computer is in charge of logic operation, while the lower manufacturing. This division has fully exerted the advantages of upper and lower computers, thus the lower computer is free from complex logic operation, the system scanning cycle is greatly reduced (within 100ms) and the system operation efficiency is greatly improved. Meanwhile, the designing flexibility of the upper computer maximizes the data storage, management and analysis.


Human Machine Interaction Diagram


Order driven operation is another highlight of this system. After formula is selected and task is generated, you only need to click “Start” and the manufacturing will start until the task is completed. The system would automatically end the manufacturing control process without human operation. The system can even realize multi formula continuous manufacturing, the switching procedure between different formula would be completed automatically and the manufacturing parameter would also be changed automatically.


 In terms of controlling logic, the upper computer has realized the separation and real time combination ofbin position and materialnumber parameter. It supports bin change operation and guarantees the proportioning accuracy after bin change. Meanwhile, the optimized control computation can effectively analyze the proportioning result, adjust the parameters based on the analysis, and improve the proportion accuracy. If a serious deviation occurs in the proportioning process, the system would pause automatically and guide relevant operators to deal with it.


2. Installation


Installation of micro weighing scale within ten digits


Installation of micro weighing scale above ten digits and within twenty meters from the proportioning scale

 Installation of micro weighing scale above ten digits further than twenty meters from the proportioning scale

3.  Applicable circumstances and market performance


PLWC micro weighing scale is applicable in feed manufacturing enterprises with annual capacity above 30,000 tons or the single batch formula being revised no more than twice. If the annual capacity is too low, the investment reward rate will be affected, therefore it is not recommended. If the formula is frequently revised, micro residue and cross contamination will be caused, therefore it is also not recommended. In other words, the higher the plant intensification and scale is, the higher the profit is.


Up until May, 2014, 72 sets of this product has been ordered, among which 33 sets have been put into production.