This style of plug is not designed to be taken apart. However with some effort, they can be dismantled to see what is inside.
This style of plug is fitted to a majority of new appliances, since they are cheaper and quicker to fit than the manually wired type.
This particular plug was attached to a vacuum cleaner, and a fault developed where if the flex was moved, the device would not work. Move the flex again, and normal operation is resumed.
As these plugs are moulded onto the flex, the only possible repair was to cut this plug off and fit another one.
After removing the strain relief, the line wire (brown) pulled out of the plug with no effort at all. It apparently had not been crimped properly when the plug was assembled, the only connection being the fact that the wire was placed into the crimp cup.
Inside, the crimps on the neutral and unused earth terminals have been completed correctly. The line terminal has a crimp mark, but it is shallower that the others, indicating it was not properly crimped. The line terminal is made from a different type of metal.
The terminal broke off, although this was probably due to the excessive forces required to dismantle the plug, rather than a defect with the terminal.
When disposing of these plugs after cutting them off, the plug must be physically destroyed to prevent it being inserted into a socket.
The bare wires would be a serious shock hazard if it was plugged into a socket.