In one embodiment, a surface having a sealing groove formed therein. The sealing groove is configured to accept an elastomeric seal. The sealing groove includes a first portion having a full dovetail profile and at least on a second portion having a half dovetail profile.

The present invention relates to a system and method of inspecting and relieving pressure and fluid from a pipeline in a safe and environmentally friendly manner. An adjustable insert is placed within a flange of the pipeline, where the adjustable insert has a valve stem capable of moving into contact with a valve device to regulate fluid or gas from the pipeline and one or more outlets for relieving pressure or withdrawing fluid from the pipeline. The system and method provided are capable of operating in a closed process without loosening or removing a flange of the pipeline, thereby improving pipeline operator safety.

A fuel head assembly (120) for a pulverized coal nozzle includes removeable back cover (123) that may be removed substantially horizontally to allow access to liners (141,143,145) inside of the fuel head assembly (120) for servicing. This may be used in places where there access from above the fuel head assembly (120) is restricted. The liners (141,143,145) are constructed of a wear-resistant material and include curved vanes (131,133) for more evenly distributing pulverized solid fuel particles, and for reducing erosion of the fuel head assembly (120).

A fuel head assembly (120) for a pulverized coal nozzle includes removeable back cover (123) that may be removed substantially horizontally to allow access to liners (141,143,145) inside of the fuel head assembly (120) for servicing. This may be used in places where there access from above the fuel head assembly (120) is restricted. The liners (141,143,145) are constructed of a wear-resistant material and include curved vanes (131,133) for more evenly distributing pulverized solid fuel particles, and for reducing erosion of the fuel head assembly (120).

A pipe system has an elbow 70 with a snake-passing opening 72 (FIG. 3) that is normally closed by a plug 88, with the walls of the snake opening and plug constructed to avoid harmful wear during use of the snake. The elbow forms a nipple 82 that surrounds the snake opening. The nipple has threads (102, FIG. 4) on its outside so snake-caused wear does not initially occur in the threads. The snake opening has an axis 108, and the plug middle forms a cup 112 that extends axially inward to block a majority of the volume within the inner end of the nipple.

A pipe system has an elbow 70 with a snake-passing opening 72 (FIG. 3) that is normally closed by a plug 88, with the walls of the snake opening and plug constructed to avoid harmful wear during use of the snake. The elbow forms a nipple 82 that surrounds the snake opening. The nipple has threads (102, FIG. 4) on its outside so snake-caused wear does not initially occur in the threads. The snake opening has an axis 108, and the plug middle forms a cup 112 that extends axially inward to block a majority of the volume within the inner end of the nipple.

There is provided herein a pipeline closure which is machined as a single piece. In this embodiment, the pipeline closure comprises a door frame which is integral to a flange containing some number of holes for lug bolts along its periphery, the purpose of the holes being to provide a means of attaching the closure to the end of a pipe as is conventionally done. A door is positionable to be opened to allow access to the interior of the pipe or pressure vessel to which the quick opening closure is attached. Unlike prior art closures, the quick opening closure does not have a weld joint that is a potential weak point in the mechanism. Additionally, this embodiment does not require as much space to mount or attach as prior art closures.

An assembly to coupling a pipeline closure with a pipeline closure hub, the pipeline closure hub including a closure hub opening portion and a coupling portion. The coupling including a pipeline closure extension extending from the pipeline closure. The pipeline extension including a junction portion to abut the closure hub opening portion of the pipeline closure hub and a fastener extending around the closure hub.

A lid (3) adapted for fluid tight sealing engagement with an opening (2) in a closed system where a pressure on an outside of the closed system is higher than a pressure on an inside of the closed system, wherein the lid is arranged to perform a pivoting movement around a pivot axis for opening the lid.