Sled device

A sled device for measuring the depth of screw channels, barrier flight undercuts, and mixer flight undercuts is shown in Fig. 10.1. To use this device, the sled is positioned on the top of the screw with the micrometer tip contacting the top of the flight. The micrometer is zeroed at this position. Next the sled is slid axially on the screw, and the micrometer is adjusted until the top of the micrometer probe contacts... 

Louvers are probably the most common type of temperature control device on aerial coolers. They may be either automatically adjusted by sensing the process temperature or manually adju.sled. Blade pitch is probably second most common, and variable speed drive is third. 

Smith [25] has described a device for sampling immediately above the sediment water interface of the ocean. The device consists of a nozzle supported by a benthic sled, a hose, and a centrifugal deck pump, and is operated from a floating platform. Water immediately above the sediment surface is drawn through the nozzle and pumped through the hose to the floating platform, where samples are taken. The benthic sled is manipulated by means of a hand winch and a hydrowire. 

The drag sled snrface sampler (Fignre 3.5) is a simple device constructed of a 7.6-cm X 7.6-cm x 1.9-cm thick block of wood or other material, which is used to hold down a 10-cm x 10-cm piece of denim cloth sampling medium as it is dragged across the floor. The bottom of the block is covered with solveut-riused aluminum foil and the denim patch is placed over the foil. Staples or push-pins are typically used to secure the sampling medium to the block. A 3.6kg weight is centered on top of the block to provide a downward pressure of 4500 Pa. The... 

Of the three techniques, the PUF roller most closely approximates the human hand press in the quantities of pesticide residues collected per unit area of surface sampled, although it collects several times as much as the dry palm of the hand. The pliable foam sampling material, especially when wetted, more closely resembles human skin than the cotton fabrics used by the drag sled and California roller. However, since the transfer rates for the latter two devices are much higher than that of the PUF roller, they are less prone to yield non-detectable results in the field. 

Many new robotic designs are being created. Vehicles looking like the lunar excursion module are common in bomb disposal units. Robotic backhoes and other devices are now in use. However, the concept of robotics can be as simple as placing an explosive ordnance item on a 3-in. foam rubber cushion atop a child s plastic basin-shaped sled and pulling it via a 200-ft nylon rope to a sandbagged detonation area. 

When short lengths or small areas are to be surveyed, the GPR device can also be operated by hand such as on a trolley or pulled on a sled across the ground. Figure 16.56a shows a GPR device with the GPS facility on a trolley. 

Oil and gas pipeline and exploration Power for instrumentation for examination devices, underwater sleds for external pipeline and drilling rig base examination, down-hole instrumentation power, heated diving suits. 

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