Abstract: A pre-defined conduit knockout is formed as a unitary part of an electronics enclosure so that before its removal the knockout is joined to the housing at a continuous unbroken surface, thereby preventing debris and liquid from entering the housing from around the knockout. The knockout is bounded by a reduced thickness break-away section of an enclosure wall that shears apart to separate the knockout from the enclosure. The knockout is formed with a unitary, pocketed tool receptor adapted to receive a tool, such as a screwdriver or pliers, for twisting the knockout free of the housing without the need to apply an impact force, which could upset sensitive electronics in the enclosure. Methods of forming the knockout in, and removing it from, an electronics housing are also disclosed.

Abstract: The improved valve assembly controls flow of fluid in "stream sampling" applications. The assembly valve block has at least two inlet passages, an outlet passage and a separate flow control valve for connecting each inlet passage to the outlet passage. Each valve has a single primary valving surface and each of the two inlet passages is selectively placed in flow communication with the outlet passage by positioning one of the primary valving surfaces. Actuation of each valve places the corresponding inlet passage in flow communication with an outlet passage common to all inlet passages. Both ends of the outlet passage are connected together by a "smooth bend" curvilinear tube attached to a fluid analyzer. The assembly can be operated by a control device for "programmed" stream sampling.

Abstract: A variable pressure reducing device for reducing high pressure in steam and hot water samples forces the liquid through an annular passageway between a pair of rods within a complementary pair of tubes. The flow rate through the rod-in-tube device, or the pressure drop across the device, is adjustable by means of a rotatable guide screw for adjusting the position of the rods within the tubes. The rods are tapered to provide a smooth flow of liquid through the device. The seal around the guide screw is self energized by means of a seal jacket between a valve gland and a stem portion of the guide screw constructed so that the biasing force of a spring on the seal jacket is supplemented by pressure from liquid flowing through the device. The guide screw is centered within the valve gland to keep the guide screw properly aligned, particularly when the device is used with a motor for rotating the guide screw to adjust the position of the rods.

Abstract: A turbidimeter includes a housing having a cavity with an inlet through which the fluid enters the bottom of the cavity, and an outlet through which the fluid exits the top of the cavity. A removable baffle assembly is located within the cavity between the inlet and outlet. The baffle assembly is formed by three vertical plates spaced from each other and extending across substantially the entire cross sectional area of the cavity. The first plate defines a first passage near the top of the cavity through which all the fluid entering the cavity must flow. The second and third walls define a second passage near the top of the cavity through which gas bubbles entrained in the fluid travels to the outlet. A third passage is defined between the first wall and the outlet and a mechanism is provided for measuring the turbidity of the fluid flowing through the third passage. A calibration device formed by a block of glass ceramic material is insertable in the third passage to simulate a known turbidity fluid.

Abstract: A perforated plastic baffle for a shell-and-tube heat exchanger includes pressure actuated tube seals. Heat exchanger tubes run lengthwise through a cylindrical shell, and baffles traverse the tubes. The pressure actuated seals line each baffle perforation through which the tubes extend. Each seal includes a flexible annular lip that surrounds the tube and extends upstream from the baffle. Fluid flowing through the shell and being redirected by the baffles provides a pressure differential that forces the seals' lips tightly against and around the tubes. In the absence of the fluid pressure differential, the sealing force is greatly reduced which enables the tubes to be easily inserted through the baffle perforations during assembly of the heat exchanger.

Abstract: A variable pressure reducing device for reducing high pressure in steam and hot water samples forces the liquid through an annular passageway between a pair of rods within a complementary pair of tubes. The flow rate through the rod-in-tube device, or the pressure drop across the device, is adjustable by means of a rotatable guide screw for adjusting the position of the rods within the tubes. The rods are tapered to provide a smooth flow of liquid through the device. The seal around the guide screw is self energized by means of a seal jacket between a valve gland and a stem portion of the guide screw constructed so that the biasing force of a spring on the seal jacket is supplemented by pressure from liquid flowing through the device The guide screw is centered within the valve gland to keep the guide screw properly aligned, particularly when the device is used with a motor for rotating the guide screw to adjust the position of the rods.