With the following program based on the groundwork calculations of Roloff/Matek, 13. edition 1994, splined shaft connections can be dimensioned.

From this program splined shaft connections with even flanks and inner centrality accord. to DIN ISO 14 (light row) DIN ISO 14 (average row) as well as DIN 5464 (heavy row) can be dimensioned.

Input data:

Splined Shaft Connections	
 	
Usage factor	KA =	 1	
Standard torque	Tnenn :	 145000	N*mm	
Hub length (= carrying spline length)	L :	 0	mm	
Advanced safety ag. surface pressure	Sp =	 4	
 	
Splined shaft row	DIN ISO 14 (light row)	
Number of splines	n :	 6	
Inner diameter	d :	 26	mm	
Outer diameter	D :	 30	mm	
Spline width	b :	 6	mm	
Take the bevel into account	No	

Shaft - material (strength values) according to	Own assignment	
 	
Material designation	 C45	
Material number	 1.0503	
 	
Material group	 Heat treatable steel	
Heat treatment / State	 heat-treated	
 	
Standard dimension	dNm =	 16	mm	
Standard dimension	dNp =	 16	mm	
Ultimate strength for dNm	RmN =	 700	N/mm²	
Yield point for dNp	RpN =	 490	N/mm²	
Modulus of elasticity	E =	 210000	N/mm²	
Poisson's ratio	n =	 0.3	
Density	r =	 7850	kg/m³	
Elongation at break	Amin =	 14	%	
 	
Yield point ratio Rp/Rm	Rp/Rm <= 0.75	
 	
Temperature	T =	 40	°C	
 	
Material, surface hardened	no	
Loads mainly crosswise to the preferred direction of machining (rolling)	no	
 	
Hub - material (strength values) according to	Own assignment	
 	
Material designation	 C45	
Material number	 1.0503	
 	
Material group	 Heat treatable steel	
Heat treatment / State	 heat-treated	
 	
Standard dimension	dNm =	 16	mm	
Standard dimension	dNp =	 16	mm	
Ultimate strength for dNm	RmN =	 700	N/mm²	
Yield point for dNp	RpN =	 490	N/mm²	
Modulus of elasticity	E =	 210000	N/mm²	
Poisson's ratio	n =	 0.3	
Density	r =	 7850	kg/m³	
Elongation at break	Amin =	 14	%	
 	
Yield point ratio Rp/Rm	Rp/Rm <= 0.75	
 	
Temperature	T =	 40	°C	
 	
Material, surface hardened	no	
Loads mainly crosswise to the preferred direction of machining (rolling)	no	

Results:	

Profile designation:   DIN ISO 14	       6 x 26 x 30	

Minimum value hub length	Lmin	=	     10.25	 mm	
Carrying spline height	h'	=	      2.00	 mm	
Mean profile diameter	dm	=	     28.00	 mm	
Existing surface pressure	pm	=	    112.32	 N/mm²	
Allowable surface pressure	pzul	=	    112.32	 N/mm²	
Existing safety	Sp	=	      4.00	

Ultimate strength for shaft	Rm	=	    675.51	 N/mm²	(for deff =	     30.00	 mm	)	
Ultimate strength for hub	Rm	=	    675.51	 N/mm²	(for deff =	     30.00	 mm	)	
Yielding point for shaft	Re	=	    449.28	 N/mm²	(for deff =	     30.00	 mm	)	
Yielding point for hub	Re	=	    449.28	 N/mm²	(for deff =	     30.00	 mm	)	

Notice:	
- Attention: ultimate strength of shaft material bigger than hub
  material needed !	
- Use body center when exact circulation is needed. Flank center
  is recommendable for dynamical loading.