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A new method of producing thin-walled seamless metal belts is discussed. The method incorporates the principles of float-rolling (CBS rolling), whereby metal strip is pinched between a small diameter floating roll and two large diameter back-up rolls which rotate with different peripheral speeds. Whereas in conventional rolling reduction may be controlled by regulating the roil gap opening, in float-rolling reduction is insensitive to changes in roll gap opening and is controlled instead by varying the speed differential between the two back-up rolls. In this report, the relationships between reduction and roll speeds, roll gap opening, and strip tension are described, and some observations of rolling loads and torques are reported. Several problems associated with the production of belts by the float-rolling method are also discussed. [ABSTRACT FROM AUTHOR]

The yarn torque developed by the applied tension in the torsion-balance apparatus described in Part 1 of this series is calculated by using an expression derived in an earlier paper. Differences in shape of net-torque-twist curves are studied for nylon monofilaments and model plied yams; these differences in shape are related to friction effects and to the mechanical properties of the constituent filaments. The torsional rigidity of the yarns is evaluated from the initial slope of the torque-twist curves for a series of nylon monofilaments; the torsional rigidity and torsional modulus are also calculated from the load-extension curve of a closely wound helical spring by employing the classical theory of elasticity. [ABSTRACT FROM AUTHOR]

A torsion-balance apparatus, incorporating a photopotentiometer device and developed to study the torsional-hysteresis and torque-relaxation behaviour of both monofilament and multifilament yarns under conditions of constant tension, is described. Differences in the shape of the torsional-hysteresis curves are studied for nylon monofilament and multifilament yarns- these differences in shape are related to friction effects and to the mechanical properties of the constituent filaments. [ABSTRACT FROM AUTHOR]

The article examines the relative functions of speed and torque in air-turbine dental contra-angle handpieces. The measurement of the rotational speed during actual cutting was required for each condition of power and load. Provided is the data that was recorded from the brass cutting test as well as the actual rotational speeds.

This report presents recommendations for structural design, materials, and con-struction of concrete tanks, reservoirs, and other structures commonly used in water and waste treatment works where dense, impermeable concrete with high resistance to chemical attack is required. Special emphasis is placed on a structural design which minimizes the possibility of cracking and accommodates vibrating equipment and other special loads. Proportioning of concrete, placement, curing and protection against chemicals are also described. Design and spacing of expansion and con-traction Joints receive special attention. [ABSTRACT FROM AUTHOR]