Abstract: A plunger type lock has an elongate shank or housing with an enlarged head at one end and at least one lock element movable to project from the housing to engage a grooved or recessed member and lock the same to the housing and to retract into the housing to release the grooved or recessed member, a plunger movable in the housing by a special key to control the position of the lock element and an immovable security rod extending through the plunger and axially substantially to the end of the housing through which the key enters. Due to the presence of the security rod, a special key is required to operate the lock.

Abstract: A rotary plug valve has a body providing a seat for a rotatable valve member which has an operator surrounded by a portion of the body and which may be rendered inaccessable by a cover closing the surrounding portion of the body and lockable to the valve member.

Abstract: A locking valve has a housing defining a fluid flow passageway, a stem bore and a lock bore intersecting the stem bore. A plug or stem may seat in the stem bore for movement between passageway opening and closing positions. A locking device is disposed in the lock bore and is arranged automatically to arrest and prevent movement of the stem upon its movement to a desired locked position such as when it closes the passageway.

Abstract: A rotary plug valve capable of being locked in selected positions includes a body and a valve member rotatable in the body between valve open and closed positions. Transverse bores are formed in the body and valve member for reception of a locking pin having a first enlarged head on a reduced shank and a second enlarged head capable of receiving the reduced end of the shank and of being locked thereto. The bore in the body is of a size to receive the heads, the central portion of the bore in the valve body being of a size less than the diameter of the heads but sufficient to receive the shank of the locking pin so that once locked, the pin may not be removed and the valve body and valve member may not be rotated relatively to one another. The pin may be unlocked by a key axially inserted into the shank through one of the heads.