# What is runout measurement?

## What is runout measurement?

According to ASME/ANSI B5.54-2005 Methods for Performance Evaluation of Computer Numerically Controlled Machining Centers, “runout” is the total indicator reading (TIR) of an instrument measuring against a moving surface. This is usually a rotary motion and is measured for a full rotation.

## What is a run out test?

Runout is a condition where the centerline of the coupling or shaft has deviated from its true axis of rotation. To measure coupling or shaft runout, it is common to use a dial indicator with a standard magnetic base. Simply mount the magnetic base on a stationary surface.

What is run out tolerance?

Run-out tolerance is a geometric tolerance that specifies the run-out fluctuation of a target’s feature when the target (part) is rotated on an axis (specified straight line). A datum is always necessary to indicate run-out tolerance; as such, it is a geometric tolerance for features related to datums.

### What is the runout symbol?

The runout symbol is a diagonal arrow pointing northeast (↗). It is a reference to how we measure the runout of a feature. We use a dial or height gauge to measure runout so the symbol actually represents the pointer in a dial gauge. The runout symbol is placed in the first compartment of the feature control frame.

### What is difference between runout & total runout?

What, then, is the easiest way to think of runout vs. total runout? Circular runout controls only a particular circular cross section of a part, while total runout controls the entire surface of the part.

How much runout is acceptable on a driveshaft?

0.020 inch
Dynotech recommends tube run-outs at 0.020 inch or less over the entire length of the tube. During both the weld and balance phase of the driveshaft development, run-out should be checked and minimized (Drawing A).

#### What is run out in mechanical engineering?

Run-out indicates to what extent surfaces of rotation when being rotated around its axis will keep a constant distance with the axis; without deviation. Run-out tolerances give the permissible deviation in the surface/axis distance of surfaces rotated about certain axis.

#### What is difference between circularity and runout?

Circularity is how round a shaft is. Runout is a measurement of how close the spinning axis is to it’s centre line.

How many places should you measure driveshaft runout?

With the vehicle on a lift, check shaft runout at three locations—the center of the shaft length and within 2 in. of each weld (front and rear).

## What causes driveshaft runout?

Some of the variables that contribute to runout are bearing internal clearance, bearing mounting clearance, the shaft being out of round, manufacturing eccentricity, and shaft loading conditions.

## How many places should you measure driveshaft runout and what tool do you use?

Measure driveshaft runout in three locations on each shaft. ◦ 3” from each end of and center of the tube. ◦ Interaxle shafts can be measured in the center only. ◦ For accurate measurements, the paint should be removed first.

How much runout should a driveshaft have?

Shaft runout is held to less than 0.015″ All driveshafts are balanced to less than 0.12 oz-in. All driveshafts are built to within 1/16″ (0.0625″) All driveshafts are high speed balanced between 5,000 and 8,000 RPM.