The invention relates to an inertization apparatus for inerting a working volume in a chemical production plant by flushing with inert gas, where the chemical production plant comprises a plant-wide inert gas distribution system having pipes for distributing the inert gas and at least one inert gas offtake position which can be connected to a connecting conduit. According to the invention, it is provided that the connecting conduit between inertization apparatus and working volume is connected, at its end nearest the working volume, in a not reversibly detachable manner to an intermediate piece, where the intermediate piece can be connected in a reversibly detachable manner to a counterpiece provided on the working volume.

The invention relates to an inertization apparatus for inerting a working volume in a chemical production plant by flushing with inert gas, where the chemical production plant comprises a plant-wide inert gas distribution system having pipes for distributing the inert gas and at least one inert gas offtake position which can be connected to a connecting conduit. According to the invention, it is provided that the connecting conduit between inertization apparatus and working volume is connected, at its end nearest the working volume, in a not reversibly detachable manner to an intermediate piece, where the intermediate piece can be connected in a reversibly detachable manner to a counterpiece provided on the working volume.

A sealed sleeve installed at an insertion coupling portion in a state in which a first pipe and a second pipe are insertion coupled to each other in order to seal couple the first pipe having a first outer diameter and a first inner diameter and the second pipe having a second outer diameter and a second inner diameter larger than the first outer diameter includes: a pillar shaped-main body having a main body central shaft; a through-hole formed using the main body central shaft as a central shaft on the main body and having an inlet as a second pipe side opening in an installation state and an outlet as a first pipe side opening in an installation state, wherein in the through-hole, a pressing portion that applies a sealing pressure to the insertion coupling portion is formed in a portion of an inner wall, and an inner diameter of the pressing portion is smaller than the second outer diameter.

A sealed sleeve installed at an insertion coupling portion in a state in which a first pipe and a second pipe are insertion coupled to each other in order to seal couple the first pipe having a first outer diameter and a first inner diameter and the second pipe having a second outer diameter and a second inner diameter larger than the first outer diameter includes: a pillar shaped-main body having a main body central shaft; a through-hole formed using the main body central shaft as a central shaft on the main body and having an inlet as a second pipe side opening in an installation state and an outlet as a first pipe side opening in an installation state, wherein in the through-hole, a pressing portion that applies a sealing pressure to the insertion coupling portion is formed in a portion of an inner wall, and an inner diameter of the pressing portion is smaller than the second outer diameter.

A fracturing fluid delivery system with a fluid conduit having a communication line is provided. In one embodiment, a fracturing system includes a wellhead assembly and a fracturing fluid conduit coupled to the wellhead assembly to enable receipt of fracturing fluid by the wellhead assembly from the fracturing fluid conduit. The fracturing fluid conduit includes a body defining a bore for conveying the fracturing fluid to the wellhead assembly and also includes a communication line. The communication line transmits signals along the body of the fracturing fluid conduit such that the fracturing fluid conduit facilitates transmission of both the fracturing fluid and the signals. Additional systems, devices, and methods are also disclosed.

A firefighter safety system and tools purposed for extracting oneself from out of a burning and smoke infested compartment of a building structure where the floor has caved in. Disclosed is a hand tool and foot tool that a firefighter can use alongside with a pressurized fire hose whereby the hand tool and foot tool can engage the fire hose in frictional contact whereby the firefighter can pull with their hand on the tool and push with their foot on the foot tool until they extricated themselves from dangerous conditions.

A fibre-reinforced polymer component is provided which comprises a main portion comprising fibre-reinforced polymer and at least one surface and at least one raised feature extending from said surface. The at least one raised feature consists of non-reinforced polymer and is shaped to incur visually perceptible damage when the component is subject to an impact with an energy above a predetermined impact energy threshold and to resist an impact with an energy below the predetermined impact energy threshold. The at least one raised feature thus provides a clear visual aid as to when a component has experienced an impact with an energy above the impact energy threshold. Because the raised feature consists of polymer without fibre reinforcement, it is more fragile than the fibre-reinforced polymer main portion 204 and thus reduces the energy at which impacts may be detected.

A fibre-reinforced polymer component is provided which comprises a main portion comprising fibre-reinforced polymer and at least one surface and at least one raised feature extending from said surface. The at least one raised feature consists of non-reinforced polymer and is shaped to incur visually perceptible damage when the component is subject to an impact with an energy above a predetermined impact energy threshold and to resist an impact with an energy below the predetermined impact energy threshold. The at least one raised feature thus provides a clear visual aid as to when a component has experienced an impact with an energy above the impact energy threshold. Because the raised feature consists of polymer without fibre reinforcement, it is more fragile than the fibre-reinforced polymer main portion 204 and thus reduces the energy at which impacts may be detected.

Pliable-wall air ducts with internal expanding structures are disclosed. An example air duct system includes an air duct including a pliable sidewall. The example air duct system further includes a shaft including a first end and a second end. The shaft extends in a longitudinal direction along a length of the air duct with the first end coupled to a first point of the air duct and the second end coupled to a second point of the air duct. The first point is downstream of the second point. The pliable sidewall is to be held in tension in the longitudinal direction between the first and second points in response to compression in the shaft between the first and second ends.

Pliable-wall air ducts with internal expanding structures are disclosed. An example air duct system includes an air duct including a pliable sidewall. The example air duct system further includes a shaft including a first end and a second end. The shaft extends in a longitudinal direction along a length of the air duct with the first end coupled to a first point of the air duct and the second end coupled to a second point of the air duct. The first point is downstream of the second point. The pliable sidewall is to be held in tension in the longitudinal direction between the first and second points in response to compression in the shaft between the first and second ends.