How often do atmospheric pressure storage tanks need to be inspected? How to detect it?

I think this issue has come up before; I checked, and for the inspection of pressure vessels at normal pressure, one of the steps is to evacuate the bottom area in order to detect any leaks there； 2. Hydrostatic test to check for leaks in the cylinder body ； 3. Used equipment must undergo thickness checks and anti-corrosion inspections, etc. There is a maintenance and repair procedure for atmospheric pressure vertical cylindrical welded steel storage tanks, SHS 01012-2004, which can be referenced at http://bbs.hcbbs.com/thread-322235-1-1.html

Atmospheric pressure storage tanks should be classified as fixed-pressure vessels; therefore, the inspection regulations should follow the Safety Technical Supervision Regulations for Fixed-Pressure Vessels TSG R0004-2008

Paragraph 2.1 of the \"Code for Maintenance and Overhaul of Atmospheric Pressure Vertical Cylindrical Welded Steel Storage Tanks\" (SHS01012‑2004) stipulates that the overhaul cycle is 3 to 6 years. Section 3.2.10 stipulates that a thickness inspection of the tank top and walls should be carried out once a year. For each panel in the lower two rings of wall panels on the tank wall, at least 2 points shall be measured vertically; for the panels in the other rings, 1 point can be measured per ring along the spiral staircase. The thickness measurement points should be fixed, marked, and thickness measurement records should be kept with corresponding numbers. For storage tanks with insulation layers, the insulation at the thickness measurement points should be designed as movable sections to facilitate removal and installation. Article 3.2.11 allows the thickness measurement time to be appropriately shortened or extended depending on the corrosion condition of the storage tank. 3.2.15 Use an ultrasonic thickness gauge or other testing equipment to check the degree of corrosion-induced thinning at the bottom of the tank. The specific method for measuring the base plate shall be carried out in accordance with the following two standards. JB/T 10764-2007 Non-destructive testing – Methods for acoustic emission testing and evaluation of metal storage tanks at atmospheric pressure; JB/T 10765-2007 Non-destructive testing – Methods for magnetic flux leakage testing of metal storage tanks at atmospheric pressure

What does it mean to post this question everywhere under hw197358? It seems like they do understand, right?

The inspection cycle for large atmospheric pressure storage tanks is not fixed. According to API653, the inspection of such tanks includes the wall plates, top plate, bottom plate, and accessories; the inspection cycle should be determined based on the results of the inspections. However, a maximum inspection cycle is specified, and the specific inspection methods can be followed as outlined in JB/T10764 and JB/T10765.

Atmospheric pressure vessels are not considered special equipment, and there are no specific regulations regarding their inspection intervals. Generally, it can be inspected once a year or every two years depending on the operating conditions and corrosion rate. Mainly, an ultrasonic thickness gauge is used to measure the degree of wall thinning and to check for surface corrosion.

Atmospheric pressure vessels are not subject to mandatory inspection; the using entity determines the inspection timing and items based on actual circumstances.