Refillable propane gas tank

A refillable propane gas tank, comprising:

• a propane tank body, the propane tank body comprising an accommodating cavity and a mounting opening, the accommodating cavity being configured for accommodating propane;
• a valve main body, the valve main body being connected to an inner wall of the mounting opening;
• the valve main body being provided with a liquid injecting channel and a pressure relief channel, the liquid injecting channel and the pressure relief channel being both in communication with the accommodating cavity;
• the pressure relief channel being provided with a first air outlet;
• a first sealing valve, wherein the first sealing valve is configured for sealing a liquid injecting channel, and the first sealing valve is movable between a first open position and a first closed position;
• when the first sealing valve is positioned at the first open position, the first sealing valve is configured for opening the liquid injecting channel;
• when the first sealing valve is positioned at the first closed position, the first sealing valve is configured for sealing the liquid injecting channel;
• a second sealing valve, wherein the second sealing valve is configured for sealing the first air outlet;
• the second sealing valve is movable between a second open position and a second closed position;
• when the second sealing valve is positioned at the second open position, the first air outlet is opened;
• when the second sealing valve is positioned at the second closed position, the second sealing valve seals the first air outlet;
• a liquid injecting head, the liquid injecting head being detachably connected to the valve main body;
• wherein the liquid injecting head is provided with a liquid injecting pipe, a top pressing structure and an overflow port;
• when the liquid injecting head is connected to the valve main body, the liquid injecting pipe is configured for pushing the first sealing valve to the first open position to make the first sealing valve open the liquid injecting channel, so that the liquid injecting pipe is in communication with the liquid injecting channel;
• the top pressing structure is configured for pushing the second sealing valve to the second open position, so as to make the second sealing valve open the first air outlet, so that the first air outlet is in communication with the overflow port.