Fuse keeps blowing

[AKMild]

I have a bedside lamp that has a 40w golf ball bulb in it. The plug is fitted with a 3A fuse. Recently, the fuse in the plug has blown, as has the replacement. I can't think what's causing it, as I wouldn't have thought that a 40w bulb is trying to demand more than 3A of current. Could anyone that knows anything about electrics perhaps point me in the right direction? The lamp is not earthed.

[The Builder]

I've seen this before with a clear bulb, where you can see the filament. It can burn out and then possibly (only a guess), make contact somewhere else along the filament. The new resistance is so much less that a higher current is drawn.......... blowing the fuse.

[chas2008]

unless there is a short in the cable it can only be the bulb..

[heathfield]

Tell me about it. I've had this happen with 40w golf ball bulbs from Ikea. If you're unlucky, the glass of the bulb can on occasion be blown out of the bulb's base, as has happened more than once with me. Can't explain it.

[johnk]

Remove the bulb and switch on the lamp, if the fuse goes there's a fault in the lamp if not the bulbs dodgy.