What is Pitch Circle Diameter?
The Pitch Circle Diameter (PCD) is the diameter of the circle which passes through the centre of all the studs, wheel bolts or wheel rim holes. The easiest way calculate the PCD is as follows: 1) Measure the distance ‘S’ between two adjacent studs from the centre of each hole.
What is pitch point and pitch circle?
Pitch circle: The circle, the radius of which is equal to the distance from the center of the gear to the pitch point. This is where the gear’s speed is measured. Pitch diameter: Diameter of the pitch circle. Pitch point: The point of tangency of the pitch circles of a pair of mating gears.
What is PCD vs BCD?
Chainrings are sold by number of bolts and PCD or BCD, which is the same thing and stands for Pitch Circle Diameter or Bolt Circle Diameter. Easier than diameter to measure is the centre-to-centre distance between two adjacent bolts.
What is a pitch circle used for?
The pitch circle is the circumference used as the standard of a pitch to express the size of gear teeth. Its length is the circular pitch multiplied by the number of teeth. The pitch circle is an imaginary circle and unlike the tip circle and root circle, it cannot be seen.
What is the meaning of PCD in rims?
On any trailer wheel assembly or rim, the PCD is the diameter of the circle which passes through the centre of all the wheel bolts or wheel rim holes. The center of every bolt hole lies along the edge of the pitch circle and are evenly spaced.
What does PCD stand for?
Pitch Circle Diameter
PCD stands for Pitch Circle Diameter and essentially is the measurement of how many wheel nuts or wheel bolts your vehicle has on each wheel and how far apart those nuts or bolts are placed in mm.
What does PCD mean on chain rings?
pitch-circle diameter
Crank and chainring pcd PCD (pitch-circle diameter) and BCD (bolt circle diameter) are the same thing; they measure the diameter of an imaginary circle passing through the chainring fixing bolts and determine the smallest chainring that can be fitted to a crank.
How do you measure BCD?
Look at the photos and compare to your crank or chainrings. Find the number of bolts in the circle (Left Column) and the approximate measurement (metric or English) between adjacent holes. Find those numbers in the table, then in the Right Column you’ll see the Bolt Circle Diameter (BCD).
What is pitch circle in simple words?
Definition of pitch circle : a pitch line in a circular gear that forms a circle concentric with the axis of the gear.
How do you calculate pitch of a circle?
Wheel PCD Measurement Calculation Formula
- 4 Stud PCD = Stud distance divided by 0.7071 to get PCD.
- 5 Stud PCD = Stud distance divided by 0.5878 to get PCD.
- 6 Stud PCD = Stud distance divided by 0.5 to get PCD.