Number of Bushes or Pins of Bushed Pin Coupling given Torque Calculator

Number of Pins Formula:

\[ N = \frac{2 \times M_t}{P \times D_{pins}} \]

Torque Transmitted by Coupling:

Force on each Rubber Bush or Pin:

Pitch Circle Diameter of Pins:

Number of Pins in Coupling:

1. What is Number of Pins in Bushed Pin Coupling?

Definition: This calculator determines the number of pins required in a bushed pin coupling based on the transmitted torque, force per pin, and pitch circle diameter.

Purpose: It helps mechanical engineers and designers properly size flexible couplings for power transmission systems.

2. How Does the Calculator Work?

The calculator uses the formula:

\[ N = \frac{2 \times M_t}{P \times D_{pins}} \]

Where:

\( N \) — Number of pins
\( M_t \) — Torque transmitted by coupling (Nm)
\( P \) — Force on each rubber bush or pin (N)
\( D_{pins} \) — Pitch circle diameter of pins (m)

Explanation: The torque is distributed among the pins based on their distance from the center (pitch diameter) and the allowable force per pin.

3. Importance of Proper Pin Calculation

Details: Correct pin count ensures even load distribution, prevents premature wear, and maintains coupling integrity under operational torque.

4. Using the Calculator

Tips: Enter the torque in Nm, force per pin in N, and pitch diameter in m. All values must be > 0. Results are shown with ±5% tolerance.

5. Frequently Asked Questions (FAQ)

Q1: Why is the pitch circle diameter important?
A: It determines the torque arm length - pins farther from the center carry more of the torque load.

Q2: What's a typical force value for rubber bushes?
A: Typically 1000-1500N per bush, but consult manufacturer specifications for exact values.

Q3: Should I round up the calculated number of pins?
A: Yes, always round up to the nearest whole number since you can't have a fraction of a pin.

Q4: How does this relate to coupling size?
A: More pins generally mean larger coupling diameter to maintain proper spacing between pins.

Q5: What safety factor should I use?
A: The ±5% tolerance is included, but consider additional safety factor based on application (1.5-2x for dynamic loads).