The difference between direct head and live connector of pipe:
The live joint, as the name suggests. It is a kind of joint and can be easily disassembled. Generally, the installation of pipe entry is more. It is commonly used on threaded connections. So it's usually used in tubes of small tubes. The larger pipe diameter is usually connected with the flange and is easy to remove.
The live connector is only thread and socket, even the socket is threaded. If you have a live joint, you don't have to screw the pipe. If you don't have a threaded connection, you have to move the pipe to open the connection.
The live connection is a removable pipe fitting that is connected by a live connector, which can be removed and replaced, such as the valve side, the side of the radiator, etc. Direct is the pipe fitting in the pipeline. If the pipe is more than the length of the pipe, such as 4m, 6m, etc., it will be used directly. The valve shall be disassembled for maintenance.
The direct pure is to extend the tube further forward, which is the pipe fitting that the length of the straight pipe exceeds the length of the single pipe in the field.