Sylinderdiameter

Sylinderdiameter is the measure of the width of a cylinder, defined as the straight-line distance across the circular cross-section through the center. It is equivalent to twice the cylinder’s radius and is commonly denoted as d. In standard terminology this quantity is called the cylinder diameter.

The cylinder diameter determines several basic geometric quantities. For a solid cylinder of height h, the cross-sectional area is A = π(d/2)² = πd²/4, and the volume is V = A h = (πd²h)/4. The circumference of the circular face is C = πd. For hollow cylinders, such as pipes, the relevant measure is the outer diameter (Do) and inner diameter (Di); the cross-sectional area is A = π/4 (Do² − Di²), and the volume is A h.

Measurement and tolerances are essential in manufacturing and engineering. External diameters are typically measured with calipers or micrometers, while internal diameters use bore gauges or internal calipers. Measurements are often specified with tolerances and measured at a reference temperature (commonly 20°C) because material dimensions can vary with temperature.

Applications of the sylinderdiameter include determining flow capacity in pipes, sizing pistons and sleeves in engines, and defining clearances in mechanical assemblies. It is a fundamental dimension in design calculations, affecting cross-sectional area, stiffness, and fit. Synonyms include cylinder diameter and, in some contexts, outer diameter when referring to a hollow cylinder’s external size.