Recently, a customer wanted to customize 10L air storage tanks from us, but he would like to have 3 inches ports on the tank. After calculating, we feedbacked that we could not have 3" port on a 10L air tank, he could not understand why. As pressure vessle is special equipment, its proudction and design is under regulations, also too large ports will affect the withstand pressure.
Here we would like to introduce the engineering standards and common specifications for connector dimensions of air storage tanks (pressure vessels)
Air Tank Inner Diameter vs. Maximum Allowable Opening Diameter
1) Ports on Air tank body
·Tank Diameter≤ 1500 mm; port diameter≤Tank Diameter /2 and≤ 520 mm
·Tank Diameter 1500 mm, port diameter≤Tank Diameter/3 and≤1000 mm
2)Ports on Convex heads/end cups
Port diameter≤ head diameter/2 (no 520/1000 limitation, but requires reinforcement)
3) Ports on Conical Head
Port diameter≤ head diameter/3 (Inner diameter at the center of the connectors) and ≤ 1000 mm
Simple Calculation (Commonly Used Small Tanks)
·Di 500 mm: Maximum port diameter 250 mm
·Di 600 mm: Maximum port diameter 300 mm
·Di 800 mm mm: Maximum port diameter 400 mm (≤520)
·Di 1000 mm: Maximum hole 500 mm (≤520)
Note: Di = Inner diameter, not the outer diameter.
Number and Spacing of Ports
1) Minimum Hole Spacing (Arc Length)
· 2 holes: ≥ Sum of the diameters of the two holes
· ≥ 3 holes: Any two holes ≥ 1.5 × Larger hole diameter
2) Number of Manholes/Handholes (Mandatory)
· Di ≥ 1000 mm: At least 1 manhole (≥ DN400)
· 500 ≤ Di < 1000 mm: 1 manhole or 2 handholes
· 300 ≤ Di < 500 mm: At least 2 handholes (≥ DN100)
· Di < 300 mm: Generally no manholes, inspection holes are used with pipe plugs (≥ DN50)
Since our existing 10L air tank diameter is 159mm, the thickness is 3mm, so inner diameter is 156mm, the port Max diameter is 78mm; while 3 inches = G3 inch / DN80, pipe outer diameter 88.9mm, which is large than 78mm. To have a 3 inches port, we suggest our 15L air tank with 219mm diameter,but reinforcement is necessary.
