# Engineering Calculators

### Horsepower

#### The Amount of Power Needed to Drive a Load

The calculator takes the input shaft speed and the torque required for a given load and derives the amount of horsepower or kilowatts expended. It can also back-calculate either the torque or the speed resulting from a particular power requirement.

### Critical Speed

#### The Input Speed Which Excites the Resonant Frequency of a System

The calculator uses the diameter, unsupported length and end fixity to determine the approximate rotational speed at which resonance will occur. It can also back-calculate to determine the diameter or length based on a specific screw rpm.

### Acme Nut PV Value

#### An Acme/Trapezoid Nut Material Limitation Based on Speed and Pressure

Unit pressure on the nut (P) and surface velocity at the nut/screw interface (V) limit the use of a particular material in an application because of the resulting heat build up and accelerated wear. All Nook Industries nut materials have a limiting PV value.

This calculator compares the actual operating load and speed against the PV rating of the chosen material. Calculations for both Nook BronzAC and PlastAC materials in inch and metric units are available.

### Column Strength

#### The Compression Load at Which a Column Will Fail Due to Bending or Buckling

The calculator uses the diameter, unsupported length and end fixity to determine the approximate minimum diameter required to support a given load. It can also back-calculate to determine the diameter or length based on a specific load.

### Ball Nut Life

#### The Expected Life of a Specific Ball Nut with a Given Load

The calculator derives the expected life in inches of travel (Inch Calculator), or the expected number of revolutions (Metric Calculator) of a ball nut operating at a load which is different than the rated dynamic load.

### Modular Actuator

#### Determine the Proper Size Based on Application Loads and Life Desired

The calculator takes the inputs and assists in sizing the appropriate linear actuator for your application. Select the type of positioning system on the left, carriage configuration, and the load data.

### Ball Screw (PMBS) Torque

#### The Amount of Torque Needed to Drive a Load with and with out Preload

The calculator takes the input parameters of a given PMBS ball screw assembly and determines the amount of torque required to move a given load. In addition, it calculates the drag torque variance due to preload.

### Linear Guidance Moment Load Calculator

A uniquely bearing calculator uses application load information to determine the forces and loads you can then use to calculate life expectancy of a given runner block.