Nominal flank-pressure screen

Spline tooth load

Inputs

Declared applied torqueTUser-entered transmitted torque; transient and reversing loads are excluded.

Declared pitch diameterDpUser-entered spline pitch diameter; standard geometry is not selected.

Declared tooth countzteethPositive integer nominal tooth count in the stated spline connection.

Declared engagement lengthLeUser-entered engaged flank length per tooth.

Declared effective flank heightheUser-entered effective loaded flank height per tooth.

Declared effective load-share fractionηshare—Visible fraction from greater than 0 through 1; contact distribution is not inferred.

Tangential torque force

12,000

Declared effective loaded teeth

teeth

Force per declared effective tooth

2,000

Nominal effective-tooth flank pressure

19.048

Ft = 2T/Dp; zeffective = z·ηshare; Ftooth = Ft/zeffective; pnominal = Ftooth/(Le·he)

A first-pass number, not a code check, certification, or approval. Read the method and its limits below. What this is and is not.

Calculation snapshot

Formula version 1.0.0

Declared applied torque	300
Declared pitch diameter	50
Declared tooth count	10
Declared engagement length	35
Declared effective flank height	3
Declared effective load-share fraction	0.6

Tangential torque force	12,000 N
Declared effective loaded teeth	6 teeth
Force per declared effective tooth	2,000 N
Nominal effective-tooth flank pressure	19.048 MPa

Ft = 2T/Dp · zeffective = z·ηshare · Ftooth = Ft/zeffective · pnominal = Ftooth/(Le·he)

Shigley's Mechanical Engineering Design — splines and keys, bearing and shear area:

This printout is a record of displayed inputs and deterministic formula output. It is not an approval, certification, or engineering conclusion.

Method

Calculate tangential torque force, force per effective tooth, and nominal flank pressure from spline geometry and visible load-share fraction.

Ft = 2T/Dp; zeffective = z·ηshare; Ftooth = Ft/zeffective; pnominal = Ftooth/(Le·he)

When

Don’t

This is declared spline geometry and load-share arithmetic only. It excludes standards, tooth form, fit, root stress, fatigue, wear, misalignment, contact distribution, capacity, safety, and approval.

Shigley's Mechanical Engineering Design — splines and keys, bearing and shear area