Nitrogen hoses

Regularly eheek equipment for signs of leaks, e.g., at hose eonneetions replaee damaged or worn items. Usually the system is pre-tested with, e.g., nitrogen. 

The hose was used for a service such as steam or nitrogen, and the service valve was closed before the process valve. As a result, process materials entered the hose. 

Many suppliers of liquefied gases state that they use different hose connections for liquid oxygen and liquid nitrogen so mistakes cannot arise. However, mistakes have occurred, possibly because of the well-known tendency of operators to acquire adaptors. 

Hoses and ducts used for conveying explosive powders should be made from conducting material and be grounded throughout. Alternatively (or additionally) the atmosphere can be inerted with nitrogen, the ducts can be made strong enough to withstand the explosion, or an explosion vent can be provided. 

Heterocycle (Sections 15.5, 24.9) A cyclic molecule w hose ring contains more than one kind of atom. l or example, pyridine is a heterocycle that contains five carbon atoms and one nitrogen atom in its ring. 

Making Incorrect Assembly Impossible Plants should be designed so that incorrect assembly is difficult or impossible. For example, compressor valves should be designed so that inlet and exit valves cannot be interchanged hose connections of different types or sizes should be used for compressed air and nitrogen. 

Fixed systems may be fixed nozzles or hand hose line systems. They usually range in capacity from 68 to 1,360 kgs (150 to 3,000 lbs.). Most use a high pressure nitrogen cylinder bank to fluidize and expel the dry chemical from a master storage tank. Where immediate water supplies are unavailable, fixed dry chemical systems may be a suitable alternative. 

Dry chemical extinguishers subject to extremely low temperatures, -20°F (-29°C) or below, should use nitrogen rather than CO2 as the expellant gas (CO2 will liquefy at these temperatures). Special low-temperature hose, nozzle, and seals are also required. For more information on dry chemical extinguishers, refer to UL 299. 

The viscosity of the reaction mixture is now too high for the final polymerization to be carried out in the same apparatus . For laboratory purposes simple metal forms are sufficient.They consist of two metal plates covered with a Teflon film. A temperature-and chemicals-resistant hose (e.g., VITON A) serves as sealing and distance control.The whole set-up is pressed together with clamps until a distance of about 5 mm is reached. When filled with the hot prepolymerization mixture they are heated in a vacuum oven under nitrogen ( ) according to the following program ... 

The later US portable unit carried arid fired by one man is described by Fisher (Ref 6, p 51). It weighs 70 lbs and consists of two interconnected fuel tanks (2 gals capacity each) with a pressure tank (containing either nitrogen or air) placed between them. The pressure of the gas in the middle tank is such that it can eject the fuel with a pressure of 2000 psi. The so-called "gun system", which resembles a Browning pistol in appearance, consists of a trigger, an ignition head, and a hose to convey fuel from... 

Solid Stream A hose stream that stays together as a solid mass, as opposed to a fog or spray. Solution Mixture in which the components lose their identities and are uniformly dispersed. All solutions are composed of a solvent (water or odier fluid) and the substance dissolved called the solute . Air is a solution of oxygen and nitrogen. A true solution is homogeneous as salt in water. Solvent A substance which dissolves other substances, most commonly water but often an organic compound. 

Engineers determined that a nitrogen valve was opened to the hose connected to the tank trailer manifold. The nitrogen gas never entered because there was a closed valve atop the tank. It seems the truck driver misunderstood the recent nitrogen supply piping modification the open and closed positions on this oval handle ball valve. 

All plants have various utility fluids such as well water, compressed air, low-pressure steam, and nitrogen, and anyone who has opened a valve on a utility service expects the utility fluid to flow from the utility header and out the hose. However, if a utility hose is connected to a higher pressure system and there aren t any check valves, undesirable chemicals can back into the utility system and exit in unexpected places. 

During a polymer plant shutdown, the operator was supposed to remove the plug from and connect a nitrogen purging hose to a fitting immediately downstream from an isolating block valve connected to a depressurized system. Instead, the employee mistakenly connected to a pressurized fitting immediately upstream from the block valve, into a 350-psi... 

Any hose used to transfer a liquid, including refrigerants, that has an agency-reportable quantity listed for a spill. It does not include normal utility hoses such as steam, water, nitrogen, and air. It does not include hoses that are supplied by a contract carrier. It does not include hydraulic hoses or other such hoses that are permanently mounted as a part of equipment that has its own inspection schedule. Fire hoses are not included, but do have testing procedures for that particular service. NOTE that good judgment should be exercised with the use of all hoses, and any obvious defects should be addressed. 

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