Patent ID: 8418515

Claim:
A valve to control fluid passage using rotation of a handle relative to a body, comprising: a locking mechanism configured to maintain a locked state of the handle relative to the body; said locking mechanism comprising: a load pin inserted into a vertical hole, which is formed in the handle and vertically extends a predetermined length from a lower surface of the handle, with a diameter-reduced neck part formed in a sidewall of the load pin at a position adjacent to the upper end of the load pin, the load pin being inserted at a lower end thereof into a locking hole formed in an upper surface of the body; a master key slot formed in the handle and extending to the locking mechanism, and a master key provided for use with the master key slot, wherein, when the master key is inserted into the master key slot formed in a sidewall of the handle, an end of the master key is fitted over the neck part of the load pin, so that, as the master key is inserted into the master key slot, the load pin is moved upwards and the lower end of the load pin is removed from the locking hole, thus releasing the locked state of the handle and allowing the fluid passage to be controlled by the rotation of the handle.