Spark Out Time for Cylindrical and Internal Grinder using Machining Time Calculator

Spark Out Time Formula:

\[ t_s = t_m - \left(\frac{d_{cut}}{V_f}\right) \]

Machining Time:

Depth of Cut:

Feed Speed:

m/s

Tolerance:

Spark Out Time (s):

1. What is Spark Out Time?

Definition: Spark Out Time is the time required in passing the workpiece under the wheel, without resetting the depth of cut.

Purpose: It helps in achieving better surface finish and dimensional accuracy in cylindrical and internal grinding operations.

2. How Does the Calculator Work?

The calculator uses the formula:

\[ t_s = t_m - \left(\frac{d_{cut}}{V_f}\right) \]

Where:

\( t_s \) — Spark Out Time (seconds)
\( t_m \) — Machining Time (seconds)
\( d_{cut} \) — Depth of Cut (meters)
\( V_f \) — Feed Speed (meters/second)

Explanation: The formula calculates the additional time needed after the main grinding operation to achieve the desired finish.

3. Importance of Spark Out Time

Details: Proper spark out time ensures better surface finish, reduces grinding burns, and improves part geometry accuracy.

4. Using the Calculator

Tips: Enter the machining time in seconds, depth of cut in meters, feed speed in m/s, and tolerance percentage (default ±5%). All values must be > 0 except tolerance which can be 0.

5. Frequently Asked Questions (FAQ)

Q1: Why is spark out time important in grinding?
A: It allows the wheel to remove any remaining high spots and achieve the desired surface finish without changing the depth of cut.

Q2: What's a typical tolerance for spark out time?
A: ±5% is common, but this depends on the application requirements and surface finish specifications.

Q3: How does feed speed affect spark out time?
A: Higher feed speeds generally require longer spark out times to achieve the same surface finish quality.

Q4: Can spark out time be zero?
A: In theory yes, but in practice some spark out time is almost always needed for quality results.

Q5: Does this calculator work for all grinding operations?
A: It's primarily designed for cylindrical and internal grinding, but can be adapted for surface grinding with appropriate parameters.