Precautions for burying underground storage tanks

The yellow sand used for S / F double-layer underground storage tanks must be selected from high-quality yellow sand that will not damage the FRP.
1) The standards of high-quality yellow sand are as follows:
① Does not contain stones;
② No harmful organic matter (acid soil), sea sand is strictly prohibited;
③ The yellow sand must be used after filtering through a 7 mesh or 8 mesh filter.
 
2) In order to protect the outer surface of the underground storage tank, the following items must be strictly observed during the embedding project:
① During the embedding process, machinery, tooling, tools, etc. must not directly impact the outer surface;
② For every 300mm height buried, it needs to be watered on the yellow sand, so that there is no gap between the buried sand;
③ No debris, such as stones, should be mixed in. Once it is present, it must be removed immediately.
 
When burying double-layer underground storage tanks, always pay attention to whether the pressure gauge changes abnormally, and it must be maintained at -0.035Mpa. When the double-layer storage tank is buried, the manhole and the detection tube should be covered with iron plates to prevent sand from entering the storage tank. The pressure gauge must also be careful not to be subject to any impact and damage. The pressure gauge set on the leak detection tube is set to -0.035Mpa at the time of shipment. Regardless of any operation, you must always confirm the changes in the pressure gauge. The pressure gauge must be strictly protected so as not to cause any damage. (Once the pressure gauge is damaged, it will cause water or debris to enter, and the storage tank will lose the leak detection function, so it must be noted)
After the storage tank is completely buried, confirm the pressure gauge on the upper part of the leak detection tube. If there is no abnormality, it means that the storage tank has no problems during the entire process from lifting to installation.
 
Once the pressure changes (below 5.4Kpa), you must contact the manufacturer immediately. Any damage during the embedding process will cause a pressure drop, so you need to stop the construction immediately and contact the manufacturer for repairs in time, and the next operation can only be carried out after the repairs are qualified.