1. Known parameters 2 8-ton boilers produce steam, one used and one standby, so when calculating the sub-cylinder, we only consider the flow rate of 8t/h, the pressure of 10barg, we need to design a sub-cylinder, two inlet DN150, 7 outlet steam pipes, of which 3 DN150, DN125+DN100+DN80+DN50, 1 each.
Second, the total cylinder diameter design is Based on the Pipe Size calculation formula (Pipe Size Based on Velocity), for steam, water supply, industrial water and other single-phase fluid pipelines, according to the selected medium allowable flow rate, calculate the pipe diameter according to the following formula: Dn - Pipe Diameter,mmG - Mass Flow Rate,t/h------8t/hv - Specific volume of the medium Volume),m3/kg-----0.1813m3/kg (1MPa) w -- Medium Flow rate Generally, the Velocity of steam in the sub-cylinder shall be calculated according to the maximum flow rate of the medium in operation and the allowable maximum pressure loss of the pipe diameter (the latter shall be used as the calculation of whether the initial pipe diameter of the former is feasible). Due to the deviation between the pipe diameter and the thickness of the pipe wall, 10% margin shall be considered in calculation. And round to the standard pipe diameter.Inside diameter Dn=594.5* (8*0.1813/2) 1^2=358mm When determining the diameter of the cylinder, the influence of the size of the boiler main steam pipe on the strength of the cylinder should also be considered. According to GB150-1998 "Steel pressure vessel", when the diameter Dn of the cylinder is less than 1500mm, the maximum diameter of the opening hole d≤Dn/2, and d≤520mm.There are two inlet DN150 steam pipes in the sub-cylinder, and 7 outlet steam pipes, of which 3 DN150, DN125+DN100+DN80+DN50 each have 1, so L1=60+150=215; L2=150+150+120=420; L3=150+150+120=420; L4=150+80+120=350L5=80+150+120=350; L6=150+50+120=320; L7=50+50+120=220; L8=50+125+120=295; L9=125+150+120=395; L10=150+100+120=370; L11=100+60=160L=L1+L2+L3+... +L11+ both ends of the head + reserve =3615+615=4130mm Summary: The size of the sub-cylinder is designed as follows: the inner diameter is DN400, the length is 4.3 meters, and the bottom drain pipe is DN25.