Status And Trend Analysis Of Inspection Methods For Down Cleaning

China is a big consumer of down products and products, and is also the largest producer and exporter of feather and down products in the world. feather down The inspection is very important for improving the quality of Chinese feather and down products, enhancing the international competitiveness of China's down products, and maintaining the position of our products in the international market.

The duvet cleanliness is an important hygienic technical index in the down inspection. It shows the contents of impurities, dust and free organic matter in the down. Cleaning down products and their products will cause allergic reactions, asthma and other diseases, which will cause serious harm to human health. Accurately checking the cleanliness of eiderdown plays an important role in controlling the quality of eiderdown and its products.

1 introduction of inspection methods for feather cleanliness at home and abroad

Combing the inspection methods and standards of feather and down plumage at home and abroad, as well as enquiry related patents and literature, we found that there are four methods for down cleaning inspection: transparency meter (glass long tube), automatic turbidimeter, spectrophotometer and light-duty cleaning device based on photosensitive resistance.

1.1 introduction to transparency meter (glass long tube) method

National standard GB/T10288 - 2003 "inspection method for feather and feather", "industry standard FZ/T80001 - 2002" test method for feather and down plumage, international feather and feather Bureau Inspection Standard "IDFB test rules eleventh part B method cleanliness determination (glass tube method)" and "European standard EN1164:1999" feather feather test method - Determination of cleanliness of aqueous extract "four standards adopt diaphanous gauge (glass long tube) method, and diaphanegraph method is shown in Figure 1.

The transparency meter (glass long tube) test process: the prepared sample is poured into the container of the Diaphanometer, slowly rising the position of the container, so that the sample is passed into the calibration cylinder by the hose, and the liquid surface is gradually increased. From the top of the cylinder, the black double cross line at the bottom of the cylinder is observed downward until it disappears, and then the container is moved down slightly, so that the double cross lines appear again, and just can see clearly.

1.2 automatic turbidimeter introduction

International feather and feather Bureau Inspection Standard "IDFB test rules eleventh part A method cleanliness tester (turbidity meter method)" by automatic turbidimeter method, automatic turbidimeter appearance is shown in Figure 2, automatic turbidity tester sample bottle see Figure 3.

Automatic turbidimeter test process: put the prepared sample into the bottle of the turbidimeter, shake the bottle 2~3s, put the measuring bottle into the NTU instrument, and independently measure the NTU value after 3 times of 5S (do not move the bottle or interrupt halfway), and record the result of determination. The result report is: turbidity =XX.xxNTU.

1.3 introduction of the method of measuring the cleaning degree of eiderdown based on photosensitive resistor

The cleaning device of eiderdown based on photosensitive resistor is mainly applied to the quick inspection of cleanliness in the cleaning process of feather and down, which belongs to the field of down processing technology. The device comprises a measuring pipe, a washing machine, a cleaning water pipe, an electromagnetic valve under the washing water pipe of the washing machine, a connection of one end of the electromagnetic valve and a measuring catheter, a light source above the measuring pipe, a photosensitive resistor at the bottom of the measuring pipe, and a connection of the other end of the electromagnetic valve to the PLC. PLC is connected with a display screen, and the cleaning degree of the down is detected in real time by the photosensitive resistor, and the current down value cleanliness is obtained by comparing the measured voltage value with the parameters in the knowledge base. A sketch map of the cleaning device of the feather based on the photosensitive resistor is shown in Fig. 4..

Spectrophotometric method was used to determine the transmittance of the test solution with a length of 5cm at a 600nm wavelength. The relationship between the transmittance and cleanliness was found out, and the cleanliness height of the test solution was obtained. When the transmittance is in the range of 70~90, the relationship between transmittance and cleanliness is: {page_break}

Q= "7.7911 x T-1125.928

Medium: Q - test liquid cleanliness height value;

T - the transmittance of the test solution.

2 Analysis of inspection methods for feather cleaning at home and abroad

Diaphaneity method and automatic turbidimeter standard test method It is widely used in inspection organizations and down production enterprises. The test result is the high degree of cleanliness. The inspection device of feather cleaning based on photosensitive resistance is not a standard test method. It is mainly applied to down production enterprises.

2.1 glass long tube method (diaphaneity method) analysis

The glass long tube method is simple in operation and highly applicable (the result is expressed by the height value, which is applicable to the feather and down standards both at home and abroad).

(1) poor uniformity of test conditions and poor reproducibility of test results.

The poor uniformity of cleanliness is mainly manifested in the cleanliness glass long tube material, the cleanliness of the glass long tube, the distance between the eye and the clean glass length tube, the light intensity and the eyesight of the inspector. The standard of these parameters is not clearly defined, and it can not be completely unified in the experimental process. The test method is human eye view, and the test results are influenced by human factors, and the reproducibility of the test results is poor.

(2) the degree of automation is low.

The low degree of automation is mainly manifested in the control of liquid level rise and fall. Extraction solution The drop is efflux from the bottom of the long glass tube.

(3) low accuracy.

The minimum scale of the Diaphanometer is 10mm and the accuracy is low.

2.2 automatic turbidimeter analysis

The advantage of the automatic turbidimeter is the instrumented test, and this method also has some disadvantages, such as:

(1) the representativeness is not strong.

The method is less representative and less sampling.

(2) the reproducibility of test results is poor.

Measuring the direction of the light is horizontal. On the one hand, it can not assess the precipitation in the measuring liquid. On the other hand, the instability of the measurement results in the instability of the suspended substance in the extraction solution and the reproducibility of the test results is poor. {page_break}

(3) applicability is not strong.

The measurement results are expressed by absorbance, and the technical requirements for the feather and down feather cleanliness standards at home and abroad are all expressed in terms of height. On the one hand, enterprises are not accustomed to it, and on the other hand, they are not unified with the technical specifications of product standards.

2.3 analysis of feather cleaning device based on photosensitive resistor

The test of the device based on photosensitive resistance is generally used only for the comparison of cleanliness and improvement of the processing enterprises before and after the down water washing. The test parameters are uniform and the influence of human factors on the test results is relatively small. This method has some disadvantages, such as:

(1) applicability is not strong.

The results of this method are expressed in terms of voltage values, not the height of cleanliness specified in the existing inspection methods, and the technical requirements for the feather and down feather cleanliness standards at home and abroad are all expressed in terms of height values.

(2) the application is not extensive.

The market did not know the complete set of testing equipment using this method, nor did it realize the down production enterprise using this detection device.

Analysis of 2.4 spectrophotometric methods

The advantage of spectrophotometric method is instrumental examination, which reduces human error. At the same time, this method also has some disadvantages, such as:

(1) the representativeness of sampling is not strong.

The method is less representative and less sampling.

(2) the reproducibility of test results is poor.

Measuring the direction of the light is horizontal. On the one hand, it can not assess the precipitation in the measuring liquid. On the other hand, the instability of the measurement results in the instability of the suspended substance in the extraction solution and the reproducibility of the test results is poor.

(3) applicability is not strong.

When the transmittance of test solution is within the range of 70~90, the relationship between transmittance and cleanliness is clear.

3 concluding remarks

The existing inspection methods of feather cleaning degree are of low accuracy, poor reproducibility, low automation, and some applicability is not strong. Therefore, the inspection method of feather cleaning will be developed in the direction of standardization, high accuracy, good reproducibility, and suitable for domestic and foreign standard technical requirements.