Abstract: For use in drawing samples of e.g water from a well. The sampling pipe is formed as an extrusion in polyethylene. The profile includes three equi-spaced channels. The profile, being triangulated, is rigid and resistant to buckling, which allows the sampling pipe to be coiled for transport to the site. Sample-tubes, pumps, etc, can be inserted into the channels. The channels can be plugged for isolation of sampling ports at different depths.

Abstract: For collecting data from a water well, down-hole sensors are housed in modules. The modules are arranged to be screwed together in-line to form a vertical string. Mechanically, the modules are secured to each other only by the screw connection. Data is transmitted to the surface on a 2-wire cable, there being no other electrical connection between the modules and the surface. The modules are connected in multi-drop configuration to the 2-wire cable. Data is transmitted using time-division multiplexing.

Abstract: For use in drawing samples of e.g water from a well. The sampling pipe is formed as an extrusion in polyethylene. The profile includes three equi-spaced channels. The profile, being triangulated, is rigid and resistant to buckling, which allows the sampling pipe to be coiled for transport to the site. Sample-tubes, pumps, etc, can be inserted into the channels. The channels can be plugged for isolation of sampling ports at different depths.

Abstract: The bladder, of flimsy ptfe tubing, is attached to the stem of an end-fitting. The stem is formed with a helical screw-thread form. The tubing is heat-shrunk down over the stem. Then, a helical coil spring is screwed onto the form, whereby the thickness of the ptfe tubing lies trapped and squeezed between the stem and the spring. This manner of attaching the bladder to the stem is mechanically adequate even when the bladder tubing is of small diameter.

Abstract: The use of extruded plastic continuous-multi-channel (CMC) tubing for conveying water samples from different depths up out of boreholes is enhanced by the compressed-grommet sealing system as described. The rubber grommet is placed inside one of the many conduits of the tubing, and squeezed lengthwise, whereby the grommet expands laterally and seals and plugs the conduit. When forming a port in the conduit, an aperture is cut in the wall of the conduit, and plug-assemblies having the grommets are placed above and below the port. Ledges on the plug-assemblies engage the ends of the aperture, and operate in conjunction with spacer bars in the aperture to prevent the plug-assemblies being moved along the conduit by pressure in the conduit. Some of the conduits in the CMC tubing are left unplugged, for admitting probes, sensors, etc.

Abstract: For collecting data from a water well, down-hole sensors are housed in modules. The modules are arranged to be screwed together in-line to form a vertical string. Mechanically, the modules are secured to each other only by the screw connection. Data is transmitted to the surface on a 2-wire cable, there being no other electrical connection between the modules and the surface. The modules are connected In multi-drop configuration to the 2-wire cable. Data is transmitted using time-division multiplexing.

Abstract: For collecting data from a water well, down-hole sensors are housed in modules. The modules are arranged to be screwed together in-line to form a vertical string. Mechanically, the modules are secured to each other only by the screw connection. Data is transmitted to the surface on a 2-wire cable, there being no other electrical connection between the modules and the surface. The modules are connected in multi-drop configuration to the 2-wire cable. Data is transmitted using time-division multiplexing.

Abstract: The use of extruded plastic continuous-multi-channel (CMC) tubing for conveying water samples from different depths up out of boreholes is enhanced by the compressed-grommet sealing system as described. The rubber grommet is placed inside one of the many conduits of the tubing, and squeezed lengthwise, whereby the grommet expands laterally and seals and plugs the conduit. When forming a port in the conduit, an aperture is cut in the wall of the conduit, and plug-assemblies having the grommets are placed above and below the port. Ledges on the plug-assemblies engage the ends of the aperture, and operate in ocnjunction with spacer bars in the aperture to prevent the plug-assemblies being moved along the conduit by pressure in the conduit. Some of the conduits in the CMC tubing are left unplugged, for admitting probes, sensors, etc.

Abstract: For collecting data from a water well, down-hole sensors are housed in modules. The modules are arranged to be screwed together in-line to form a vertical string. Mechanically, the modules are secured to each other only by the screw connection. Data is transmitted to the surface on a 2-wire cable, there being no other electrical connection between the modules and the surface. The modules are connected in multi-drop configuration to the 2-wire cable. Data is transmitted using time-division multiplexing.