In GB3863-83, specific regulations are made for the product quality of industrial oxygen. According to the moisture content in the product, it is divided into two categories, and the oxygen purity of the product is further divided into two levels, as shown in the table below.
Requirements for industrial oxygen extraction surgery
|
Indicator Name |
Indicators |
|||
|
I class |
Ⅱ class |
|||
|
1 level |
2 level |
|||
|
Oxygen content (volume fraction)/%(≥) |
99.5 |
99.5 |
99.2 |
|
|
Moisture content |
Free water per bottle/mL(≤) |
|
100 |
|
|
Dew point/℃(≤) |
-43 |
|
||
There are two methods for measuring the moisture content in bottles: 1) Dew point method, which uses a dew point meter to measure the situation of low moisture content, and the measurement error should not exceed 1 ℃ of soil; 2) Inverted method. Invert the oxygen filled cylinder vertically for 10 minutes, slightly open the cylinder valve, and allow water to flow into a clean and dry container. When oxygen is sprayed out, immediately close the bottle valve and use a measuring cylinder to measure the amount of water flowing out. First class products should be free of free water.
Random sampling inspection shall be conducted on gas cylinders. The sampling number is shown in the table below. When one bottle is found to be unqualified, double the sampling inspection should be conducted. When there is still one bottle that is not qualified, the batch of products is considered unqualified.
Number of samples for bottled industrial oxygen sampling
|
Product batch/bottle |
1～8 |
9～15 |
16～25 |
26～50 |
>50 |
|
Sampling quantity/bottle |
2 |
3 |
4 |
5 |
6 |
