Abstract: A contra-flow strip for inhibiting leakage of a fluid between a rotating member and a stationary member includes, for example, a base supportable by the stationary member coaxially around the rotating member, and means, extending from the base coaxially towards the rotating member between a low pressure region and a high pressure region, for generating a contra flow of a portion of a tangential flow of fluid in the low pressure region to the high pressure region between the stationary member and the rotating member.

Abstract: A lockable manhole cover includes, for example, a manhole cover installable in an opening in a manhole frame, a locking member attached via a pin and slot arrangement beneath the manhole cover, and a lever pivotally attached to the manhole cover. A lower end portion of the lever is operably engageable with the locking member to move the locking member relative to the manhole cover. The lever is disposable in a lowered position so that an end portion of the locking member is operably engageable with a portion of the manhole frame for use in inhibiting removal of the lockable manhole cover from the manhole frame. The lever is disposable in a raised position so that the end portion of the locking member is operably disengageable with the portion of the manhole frame to allow removal or installation of the lockable manhole cover from or in the manhole frame.

Abstract: A contra-flow strip for inhibiting leakage of a fluid between a rotating member and a stationary member includes, for example, a base supportable by the stationary member coaxially around the rotating member, and means, extending from the base coaxially towards the rotating member between a low pressure region and a high pressure region, for generating a contra flow of a portion of a tangential flow of fluid in the low pressure region to the high pressure region between the stationary member and the rotating member.

Abstract: A locking assembly attachable to a manhole cover includes an arm disposable in a lowered position with the arm disposed in a first orientation engageable with a manhole frame supporting the manhole cover to inhibit removal of the manhole cover from a manhole frame, and disposable in a raised position and in a second orientation operable to allow removal of the manhole cover from the manhole frame. In an embodiment, the locking assembly may include the arm attached to a movable member having a spiral, helix, or curved groove and in which the movable arm is receivable in a bushing and a pin receivable in the groove.

Abstract: A lockable manhole cover incudes, for example, a manhole cover installable in an opening in a manhole frame, a locking member attached via a pin and slot arrangement beneath the manhole cover, and a lever pivotally attached to the manhole cover. A lower end portion of the lever is operably engageable with the locking member to move the locking member relative to the manhole cover. The lever is disposable in a lowered position so that an end portion of the locking member is operably engageable with a portion of the manhole frame for use in inhibiting removal of the lockable manhole cover from the manhole frame. The lever is disposable in a raised position so that the end portion of the locking member is operably disengageable with the portion of the manhole frame to allow removal or installation of the lockable manhole cover from or in the manhole frame.

Abstract: A locking assembly attachable to a manhole cover includes an arm disposable in a lowered position with the arm disposed in a first orientation engageable with a manhole frame supporting the manhole cover to inhibit removal of the manhole cover from a manhole frame, and disposable in a raised position and in a second orientation operable to allow removal of the manhole cover from the manhole frame. In an embodiment, the locking assembly may include the arm attached to a movable member having a spiral, helix, or curved groove and in which the movable arm is receivable in a bushing and a pin receivable in the groove.

Abstract: A manhole cover includes a support having an upper surface and a peripherally-extending portion. An outer insulating member is disposed over the entire upper surface of the support, and the support comprises a first material and the outer insulating member comprises a second material different from the first material. The peripherally-extending portion of the support is positionable over the lip of the manhole ring. The outer insulating member is positionable between the upper surface of the support and the upper surface of the rim of the manhole ring when the manhole cover is received in the manhole ring. In one aspect, the support comprises cross-members defining a grate having passageways through the support. In another aspect, the support comprises metal, and the outer insulating member comprises a composite of resin, reinforcement fibers, and stone aggregate. In another aspect, screen inserts are disposed in a plurality of passageways in the outer insulating member.

Abstract: A manhole cover includes a support having an upper surface and a peripherally-extending portion. An outer insulating member is disposed over the entire upper surface of the support, and the support comprises a first material and the outer insulating member comprises a second material different from the first material. The peripherally-extending portion of the support is positionable over the lip of the manhole ring. The outer insulating member is positionable between the upper surface of the support and the upper surface of the rim of the manhole ring when the manhole cover is received in the manhole ring. In one aspect, the support comprises cross-members defining a grate having passageways through the support. In another aspect, the support comprises metal, and the outer insulating member comprises a composite of resin, reinforcement fibers, and stone aggregate. In another aspect, screen inserts are disposed in a plurality of passageways in the outer insulating member.

Abstract: The invention pertains to a method and apparatus for minimizing the leakage of working fluid through the fluid leakage path of a turbine seal. The invention may be described in general terms as producing from rotary motion of the working fluid a region of lowered pressure in the working fluid in a portion of the leakage path adjacent a high pressure side of a sealing ring of the seal. This function may be performed by producing and shedding vortices in the working fluid at one or more points about the circumference of the sealing ring. This function may be accomplished by providing a sealing ring having a tooth portion provided in one or more tooth segments, portions of one or more trailing edges of the tooth segments extending outward in a common direction.

Abstract: A rubbing strip is used in conjunction with the sealing strips of a seal to prevent contact between the sealing strips and a rotating member with which the sealing strips form a seal. The rubbing strip comprises a strip of material which is oriented coaxially with the sealing strips and which has a clearance with respect to the rotating member which is less than the least of the clearances provided by the sealing strips with which it is associated. The material and the cross-sectional shape of the rubbing strip may be selected in accordance with desired wear properties. The rubbing strip may be formed integrally with a sealing ring, or may be formed to be inserted into complementary receiving means on a sealing ring.

Abstract: A rubbing strip is used in conjunction with the sealing strips of a seal to prevent contact between the sealing strips and a rotating member with which the sealing strips form a seal. The rubbing strip comprises a strip of material which is oriented coaxially with the sealing strips and which has a clearance with respect to the rotating member which is less than the least of the clearances provided by the sealing strips with which it is associated. The material and the cross-sectional shape of the rubbing strip may be selected in accordance with desired wear properties. The rubbing strip may be formed integrally with a sealing ring, or may be formed to be inserted into a complementary receiving recess on a sealing ring.