Abstract: A multistage automated thermally actuated valve utilizing a thermally expansive substance to substantially close the valve at a first temperature and a spring to open the valve at a second, lower temperature. A multistage automated valve comprising a first thermal assembly to balance fluid flow at a first temperature and a second thermal assembly to balance fluid flow at a second temperature in order to balance fluid flow in a system operated at a first temperature as well as at a second temperature. A method of utilizing an automated thermally actuated valve to balance and manage hot water supply in a piping system.

Abstract: A roller for engaging an outer surface of a pipe element during roll forming has a perimeter region defined by three faces. A channel is positioned in one of the faces. The channel extends circumferentially around the perimeter region and provides a void space that reduces the contact area between the face and the side surface of a circumferential groove formed in the pipe element during roll forming. The reduced contact area reduces frictional heating of the pipe and roller as well as the tendency of the roller to slip relative to the floor surface of the groove due to axial force engendered when an asymmetrical groove is formed.

Abstract: A multistage automated thermally actuated valve utilizing a thermally expansive substance to substantially close the valve at a first temperature and a spring to open the valve at a second, lower temperature. A multistage automated valve comprising a first thermal assembly to balance fluid flow at a first temperature and a second thermal assembly to balance fluid flow at a second temperature in order to balance fluid flow in a system operated at a first temperature as well as at a second temperature. A method of utilizing an automated thermally actuated valve to balance and manage hot water supply in a piping system.

Abstract: A roller for engaging an outer surface of a pipe element during roll forming has a perimeter region defined by three faces. A channel is positioned in one of the faces. The channel extends circumferentially around the perimeter region and provides a void space that reduces the contact area between the face and the side surface of a circumferential groove formed in the pipe element during roll forming. The reduced contact area reduces frictional heating of the pipe and roller as well as the tendency of the roller to slip relative to the floor surface of the groove due to axial force engendered when an asymmetrical groove is formed.

Abstract: A hydronic system controls the air temperature in a plurality of zones. The system has a plurality of heat exchangers, each one being associated with a respective zone. The mass flow rate of a working fluid through each heat exchanger is controlled to maintain the working fluid temperature drop across the heat exchanger a constant, chosen for efficient operation of the boiler or chiller which transfers heat to or from the working fluid. The flow of air in each zone through each heat exchanger is controlled by the air temperature in the zone. A respective valve associated with each heat exchanger is used to control the mass flow rate of the working fluid through the heat exchanger, and also imposes an upper limit of the mass flow rate established by balancing the hydronic system. The upper limit is controlled by a parameter proportional to mass flow rate.