A closed system for cleaning, pressure testing and drying high pressure containers, such as for fire extinguishers. The system comprises coacting open and closed sub-systems; the closed sub-system comprising two tanks for holding trichloroethane and flow lines in a valve controlled system for flowing trichloroethane from one tank into the container to be cleaned, pressure tested and dried and thence to the other tank; the open sub-system comprising an outer, invertible jacket and water tank with connecting lines and valves for filling the jacket about each high pressure fire extinguisher container and measuring the expansion under the pressure at which it is tested. The two tanks and the valve system for the trichloroethane can be reversed to allow repeated and continuous use. Also disclosed is the preferred apparatus; including the unique lid design of the jacket, as well as other features. The lid swings aside to facilitate insertion of a fire extinguisher container therewithin and has quick connect means facilitating connection and is sealingly closed to the remainder of the jacket pneumatically.

A method of and system for cleaning and maintaining water distribution pipes which have reduced flow due to an increase of water scale deposits, sediment and the like along the inside surface of the pipe includes a mobile cleaning unit which can be conveniently and easily connected to a pipe section to be cleaned. An aqueous cleaning solution is introduced and circulated in a first direction through the pipe section for sufficient time to dissolve and loosen scale and sediment. The flow direction of the treating solution is then reversed to break off or remove sediment or other tuberculated growth that has developed directionally with the direction of water flow in the pipe section. The turbulent flow in the opposite direction increases the effectiveness of the cleaning process in particularly troublesome and hard-to-clean pipe sections. The spent treating solution and other deposits are flushed from the pipe and the mobile cleaning unit to an appropriate waste stream. Advantageously, the direction of the flow of the treating solution can be reversed without disconnecting the cleaning unit from the pipe section.

In order to form an adherent coating of zinc stearate on the bore surfaces of a plurality of tubes grouped in parallel relation, an alkali cleaner solution is circulated therethrough from a reservoir tank and then returned to the tank by a flow of purge air which is thereafter vented to the atmosphere to remove any alkali residue from the system. A phosphate solution, an alkali neutralizer solution, and a stearate solution are, in turn, similarly circulated and returned to their respective reservoir tanks. Each circulation is followed by a corresponding circulation of hot rinse water which is also returned to its reservoir tank by the same air purge technique.

Apparatus for cleaning a cooling system having inlet and outlet ports for circulating a cleaning fluid. A cleaning solution is supplied to one port of the cooling system with the other port thereof communicating with a discharge conduit. Positive pressure and a negative pressure are created alternately in the discharge conduit to cause the cleaning solution to flow in opposite directions. One check valve in the discharge conduit permits flow only in response to the creation of positive pressure and another check valve permits flow only in response to the creation of negative pressure. A member restrains opening of said one check valve until there is a predetermined increase in positive pressure and an other member restrains opening of the other check valve until there is a predetermined increase in negative pressure with said another member requiring a greater force to open said other check valve than the force required to open said one check valve whereby there is major flow toward discharge and minor flow in the reverse direction.

Disclosed is a chemical cleaning process for removing fouling from process lines of oil refining or petrochemical plants. The process lines are in an on-line state and a chemical cleaning agent is circulated through the process lines to remove the fouling. It can effectively recover the thermal efficiency in oil refining processes or petrochemical processes within a short period of time, so that significant energy consumption is reduced. Furthermore, the chemical cleaning process requires a shorter cleaning period and therefore allows for a longer operating time. It can also dislodge fouling without opening heat exchangers or other equipment thereby preventing the release of VOCs. As a result, environmental pollution is not generated. The present invention is also ecconomically favorable as it extends the time between periodic maintenance.