SCBA hydrostatic testing and maintenance is very important, let’s see some cases:
- Cylinder Inner Wall Cleaning Issues
Due to the lack of timely maintenance of the air filling pump, oil and water are injected into the cylinder during the filling process. Over time, these substances adhere to the inner wall of the cylinder. Since the air breathing apparatus is used by firefighters, the inner wall of the cylinder must be kept clean; otherwise, it can cause harm to the user.
Solution: The air filling pump needs regular maintenance. The inside of the cylinder should be cleaned and dried using a neutral detergent.
2. Pitting corrosion inside the gas cylinder
This is caused by substandard gas composition. Over time, this will affect the thickness of the cylinder’s inner liner, creating a safety hazard during use.
The solution is to perform regular maintenance on the filling pump. The corrosion condition inside the cylinder needs to be assessed by an inspector. Cylinders with minor corrosion can continue to be used, while those with severe corrosion should be scrapped.
3. Applying excessive amounts of silicone grease during cylinder valve installation and removal
Lead to reaction and deterioration over time, contaminating the air inside the cylinder and posing a health risk to personnel.
The solution is to clean and wipe the cylinder opening and threads.
4. The accumulation of grease and oxides inside the cylinder forms solid dirt.
The main cause is the lack of timely maintenance of the filling pump, resulting in excessively high levels of oil and moisture in the air being filled. This can easily clog delicate components in the air respirator’s decompression device.
The solution is to regularly maintain the compressor and clean and dry the inside of the gas cylinder with a neutral detergent.
5. The threads at the connection between the cylinder and the valve are damaged and broken, resulting in fewer effective threads than specified.
This poses a safety hazard during use.
This cylinder is deemed unusable and cannot be reused.
6. This air respirator consistently reported short usage time during use. A normal air respirator has a usage time of 30 minutes, but this one only lasted 10 minutes. Even after inflation to 30 MPa and confirming no leaks at any connections, the short usage time persisted.
Subsequent cylinder airtightness and water pressure tests revealed the condition shown in the image above: multiple pinholes on the inner wall of the cylinder, indicating overall leakage. This cylinder is deemed unusable and should be discarded.
7. The threads of this cylinder valve were found to be cracked during installation and removal. It broke during installation and removal when the cylinder was depressurized. Such a defect would pose a significant danger if used under pressure.
This valve is defective and must be replaced.
8.Corrosion of the air cylinder valve’s guide tube is caused by high levels of water vapor, chloride ions, and sulfur ions in the air during filling, leading to oxidation and corrosion. This is related to whether the filling pump is maintained in a timely manner and the filling environment. This problem can cause difficulty in filling the air cylinder, and the air supply to the fighter will decrease, affecting their breathing rhythm and even causing breathing difficulties.
The solutions are to regularly maintain the filling pump, set up an independent filling chamber and install a filling cooling and drying device to maintain a good and stable filling environment, and replace the valve’s guide tube.
