DF-ISO Cast Steel High Velocity Pressure Vacuum Valve:
China DF-ISO Cast Steel High Velocity Pressure Vacuum Valve:
High Velocity Pressure Vacuum Valve is called PV valve or P/V valve for short, generally used in the relief system of the oil tanker and chemical tanker, according to the current regulations IMO and IBC.
When the pressure in the tank reaches the set pressure of relief valve, the gas in the tank will be released with the speed of over 30m/s. The vacuum will beformed while the cargo oil tank is unloading, when the vacuum pressure reaches the set pressure of vacuum valve (normally it is -3.5Kpa), the vacuum valve will open automatically,then the air will go into the tank through the flame screen.
If the pressure is too high whil the ship is sailing, the high velocity PV valve will automatically release the pressure and keep the pressure balance.
Technical Specification:
1. Design Standard: ISO 15364-2007, MSC/circ. 677, GB/T19699-2012, MSC.1/circ. 1324, MSC/circ. 1009
2. Flange Standard: GB2506, JIS B2220, ANSI, DIN
3. Design Pressure:
Opening Pressure of Pressure valve: 14Kpa for Oil cargo tank, 20Kpa fo chemical cargo tank.
Opening pressure of Vacuum Valve: -3.5Kpa.
Certificate:
CCS, BV, ABS Type Approval Certificate and Product Certificate, NK product certificate
Main Parts and Material:
| Serial No. | Parts | Quantity | Material | Remarks |
| 1 | P-valve base | 1 | ZG200-400 | Cast 20# |
| 2 | Water nozzle | 1 | 0Cr18Ni9 | SUS304 |
| 3 | P-valve seat | 1 | 0Cr18Ni9 | SUS304 |
| 4 | P-valve disc | 1 | 0Cr18Ni9 | SUS304 |
| 5 | Matching block | 1 | 0Cr18Ni9 | SUS304 |
| 6 | P-valve body (A) (B) | 1 | ZG200-400 | Cast 20# |
| 7 | Conducting machine | 1 | 0Cr18Ni9 | SUS304 |
| 8 | Handle | 1 | 0Cr18Ni9 | SUS304 |
| 9 | V-valve body | 1 | ZG200-400 | Cast 20# |
| 10 | Matching block | 1 | 0Cr18Ni9 | SUS304 |
| 11 | V-valve disc | 1 | 0Cr18Ni9 | SUS304 |
| 12 | V-valve seat | 1 | 0Cr18Ni9 | SUS304 |
| 13 | Flame screen | 2 | 00Cr17Ni14Mo2 | SUS304 |
| 14 | Flame screen gland | 1 | ZG200-400 | Cast 20# |
| 15 | Nameplate | 1 | 0Cr18Ni9 | SUS304 |
| 16 | Climbing pole | 1 | 0Cr18Ni9 | SUS304 |
| 17 | Gas-freeing cover or V-valve cover | 1 | ZG200-400 | Cast 20# |
Technical Parameters:
| Type | Desinged Opening Pressure（Kpa) | Rated Working Pressure (Kpa) | Hydraulic Test Press (Mpa) | Velocity (m/s) | Rated Flow Rate(m3/h) | |||
| Pressure Valve | Vacuum Valve | Pressure Valve | Vacuum Valve | Pressure Valve | Vacuum Valve | |||
| DF50 | 14~20 | -3.5 | 21 | -7 | 0.345 | ≥30 | 300 | 300 |
| DF65 | 400 | 400 | ||||||
| DF80 | 600 | 500 | ||||||
| DF100 | 800 | 600 | ||||||
| DF125 | 1000 | 800 | ||||||
| DF150 | 2500 | 2200 | ||||||
| DF200 | 3000 | 3000 | ||||||
| DF250 | 3500 | 3000 | ||||||
