Analysis And Discussion On Inspection And Acceptance Of National Cotton Storage By Sichuan Fiber Inspection Bureau

My bureau and

The provincial fiber inspection bureau is jointly responsible for the verification and acceptance of the national cotton store in two stages in Xinjiang city Shihezi Tian Yin logistics company. After verification work is finished, the cotton for verification and acceptance is checked according to cotton processing plant, contract number and batch number for indexes such as moisture regain, impurity, public quantity, Ma Kelong, grade and so on, and some problems are analyzed and discussed.

Problems found in verification and acceptance

1. moisture regain.

In the field inspection, the cotton moisture regain rate of the regiment was small, and the average moisture regain was below 9%. There was no problem of returning the goods due to excessive moisture regain, and the local cotton processing enterprises (most of them did not have drying equipment) were processed.

There is widespread phenomenon of moisture regain (basically around 9.5%, or even more than 10%).

Whether it is the corps or the real estate of cotton, the public inspection rebound rate is basically greater than the online regurgtion rate, the single packet inspection data, a large part of the difference is more than 3%.

There is a great difference in moisture regain between the two packages.

Because of the extreme environment (when the outdoor temperature was below 27 degrees Celsius), our bureau had used the plug type water electric detector to test the stacked cotton stacks in the enterprise. The same cotton bag had the difference of moisture regain between the two sides of the same package of cotton on the two sides of Baotou because of one head at the draught and the other side leeward. The difference was 2%.

There are problems in the use of online resurgence system.

During the inspection of a batch of cotton (the same day production), our Bureau found that the moisture regain of the cotton bags on the earlier stage was more than 10%, but the online moisture regain of the later serial numbers suddenly turned to about 6%.

The needle insertion type (MBS) moisture electric detector has a station difference.

The same number of cotton at the same time, the same insertion point, the same depth of insertion, the values of each electrical tester were inconsistent, and some differences reached 1%.

The handle of the moisture sensor is easy to damage at low temperature, especially with the connection line.

Due to the low temperature, the outer layer of the connecting line hardens, resulting in the fracture of the root of the connecting line.

2. impurity rate.

The corps cotton is machine picked cotton, the impurity is bigger, because in recent years continuous technological pformation, the basic control is about 2%.

Some factories because of management and mechanical equipment and other reasons, the production of cotton impurities, such as the 150 group of processing plants, basically around 2.5%, and some processing plants control better, such as 149 group joint processing plant, basically controlled at about 1.7%, and even some batches of impurities only 1.2%, cotton does not look like machine picked cotton, like hand picking cotton.

The local cotton processing enterprises produce cotton by hand picking, and the impurities are large. Most of them are around 2% or even 2.5%. From the aspect of cotton sample morphology, it is like machine picked cotton because of larger impurities.

3. the question of fixed weight.

The fixed weight is generally smaller than that of the original test.

The batches of cotton in the regiment are basically less than 0.6-0.8 tons per ton. Real cotton is basically less than 0.8-1.3 tons, and some batches of real estate cotton are even less than 2 tons. Some of the contract weights (10 batches) are less than 17 tons.

During the detection process, it was even found that in the case of the regurgtion rate of the public inspection is 2% larger than that of the on-line moisture regain, the gross weight of the public inspection weight is even smaller than that of the raw wool.

However, some cotton processing enterprises have very little difference between the fixed weight and the original inspection amount. The difference between the official weight and the original inspection results is within 200 kilograms. Basically, it is overweighted. Some batches are 0.4324 tons heavier than the original test results, and some enterprises have a smaller difference between the official weight and the original inspection amount, which is basically within 300 kilograms per batch.

4. micron values and grades.

In the verification process, we found that the difference between the micron value, the grade and the original test result is quite different. The difference of the micron value is mainly that the result of the verification test is smaller than that of the original inspection result.

And once these problems arise, they are concentrated on a contract number of an enterprise.

Our analysis of the problem

The weight of the enterprise is calculated by the gross weight and the online moisture regain generated by the online system of each processing plant. The data of the online detection system can only be used as reference data for the production of the enterprise, but not as a reference.

Settlement basis, according to the online system generated gross weight and online moisture regain as the basis for settlement, there are problems. Therefore, the difference between the weight of public inspection and the original inspection is not that some people are talking about the problems of needle plug type electric detector or on-line monitoring system, but the problems existing in the management of the enterprise itself.

It is particularly noteworthy that, when our Bureau inspected a contract number of cotton, the two batches of cotton were replaced by the two batch of cotton as a result of water exceeding the standard, and the weight of the other batch in the contract was less than 1 tons compared with the original test results, and the two batches of cotton were very small, with an average of less than 400 kilograms.

This shows that cotton processing enterprises are very aware of the quality inspection and weight of cotton produced by themselves, and the management concepts of different processing enterprises are different. According to their operational needs, they provide different batches of cotton and corresponding inspection data to maximize their profits.

With regard to the problem of impurity rate, we analyzed the impurity samples of real estate cotton, found that the impurities contained fiber seed chips and more cottonseed skins and shells. The reason for this situation is probably that during the continuous rainy days of the processing season, the enterprises simply pursued the processing speed, gave too much pressure to the cotton box, and saw too fast the speed of the sawtooth wire, and brought the cotton fiber together with the cottonseed hull or even the cottonseed hull, resulting in too much impurity.

At present, there is a problem in the metrological verification of the needle plug type moisture sensor (including the new type of pressure plate type moisture sensor xj130).

First, the automatic compensation method of temperature difference is adopted. When the metrological verification is carried out, it can only test the resistance of the ambient temperature at that time and compare it with the standard resistance box. If the data are consistent, it is considered qualified, and if it is not consistent, it can not be adjusted, and it can only be returned to the manufacturer for maintenance.

That is to say, the current verification behavior can only be carried out to check a certain point of its detection range. In strict sense, such verification can only determine whether the instrument is qualified at that time. If the temperature changes, whether the instrument is qualified or not, it needs to be checked. It is not as old as the old electric detector to carry out multi-point test and verification, so as to determine whether the instrument is qualified.

Two, according to the current verification regulation, the calibration range of the water electric detector can only be at room temperature (0-40 degrees Celsius), and there is no corresponding verification regulation if the instrument is qualified below 0 degrees.

Three, at present, the standard resistance boxes built in the provinces for measuring and calibrating the water electric meters are based on the mathematical model of the original resistance moisture regain (temperature compensation), which is a problem with the consistency of the mathematical models adopted by the new type of water electric measuring devices.

The difference between micron value and grade is relatively large. The main reason for this analysis is that the storage and storage enterprises try to maximize the interest, deliberately forge test data or steal samples, and attempt to disguised qualified cotton flowers as cotton which does not meet the conditions of receipt and storage (generally the C1 value is four, and the grade is less than grade 2). Secondly, the reason for the negligence of the inspection personnel in the inspection is the deviation of the inspection data.

Explore ways to solve problems

Based on the above analysis, I believe that the following aspects should be addressed:

1. needle plug type water electric detector generally reflects the cotton moisture regain, and further improvement will be better.

In particular, when cotton fiber is hygroscopic, under the extreme temperature of minus 20-30, what kind of water exists, and what kind of changes will happen when its conductivity is compared with the conductivity of cotton fiber at room temperature? All these need further basic research, and further improve the mathematical model of cotton moisture regain in extreme environment, making the instrument more convenient, more scientific and more convincing.

2. build up the metrological verification regulation and measurement standard to adapt to the new type of water electric detector, and carry out the value pfer.

Ensure that the instrument is normally used and tested accurately in field tests.

3. the instrumented inspection organizations should strengthen their communication with the enterprises being inspected. Especially during the processing period, the grade inspectors should attach importance to the processing quality of the enterprises, find out the problems, inform the enterprises in time, help the enterprises to analyze the causes and solve the problems, so as to improve the economic efficiency and the enthusiasm of the inspection.

4. the professional inspection institutions responsible for purchasing and storing tasks should strictly check the quality of the cotton stored in accordance with the inspection procedures, and pay special attention to the inspection of micronnine and grading. We must not take it lightly. We must ensure that there is a special person in the field inspection to complete the detection of the micronine value, and the inspection work should be completed in the laboratory on the same day, so as to detect problems in time.

5. the local inspection institutions should strengthen propaganda work, work hard on the supervision, ways and depth of the enterprises, constantly innovate the supervision mechanism. On the other hand, the testing organizations need to further strengthen the management of the testing personnel, standardize the operation of the personnel, and improve the accuracy of the testing data.