CYLINDRICAL WORM GEAR PAIR
CALCULATION REPORT
Order	Dware
Project	Demo
Sub project	Niemann-Winter Band III
Item	S. 102 Voorbeeld 3
ID worm	z1=1
ID gear	z2=40
Calculated by	André Dewispelaere
Company	Dware
On date	12/07/2023

1	5. Operating conditions	Symbol	Unit	Worm	Wheel
2	Desired service life	Lh	h	25000	25000
3	Service factor	ID	%	100.00	100.00
4	Roughness worm flanks	Ra1	µm	0.800	--
5	Kinematic viscosity at 40 °C oil	ν40	mm²/s	320	320
6	Kinematic viscosity at 50 °C oil	ν50	mm²/s	169	169
7	Oil type	--	--	mineral	mineral
8	Wheel transverse force alternating	--	--	no	no
9	Short operation time	--	--	no	no
10	Short operation time duration	tE	min s	0 min 0 s	0 min 0 s
11	Short shocks duration < 15 s	--	--	no	no

1	1. Application factor	Symbol	Unit	Worm	Wheel
2	Application factor	KA	--	1.00	1.00
3	2. Cooling conditions	Symbol	Unit	Worm	Wheel
4	Highest allowed oil temperature	θL	°C	90	90
5	Ambient temperature	θi	°C	20	20
6	Heat exchange area	Aca	m²	2.9000	2.9000
7	Heat exchange coefficient	kca	kW/m²°	0.028	0.028
8	Enclosure	--	--	yes	yes
9	Cooling ribs	--	--	yes	yes
10	Forced ventilation	--	--	yes	yes
11	Riding wind on enclosure	--	--	no	no
12	Riding wind velocity	vai	m/s	0.00	0.00
13	3. Desired wear limit	Symbol	Unit	Worm	Wheel
14	Wear limit in tooth thickness	DsnL	mm	0.000	0.000
15	Wear limit in mass	DmL	kg	0.100	0.100
16	4. Desired min safety factors	Symbol	Unit	Worm	Wheel
17	Safety thermal overload	ST	--	--	1.00
18	Safety contact stress wheel	SH	--	--	1.00
19	Safety wear on wheel dent	SW	--	--	1.00
20	Safety tooth root strength wheel	SF	--	--	1.40
21	Safety deflection worm shaft	Sd	--	1.00	--
22	5. Mating materials	Symbol	Unit	Worm	Wheel
23	Materials mating factor	WP	--	1.10	1.10
24	Material mating test velocity	vg0	m/s	0.13	0.13
25	6. Calculation of cooling	Symbol	Unit	Worm	Wheel
26	Permissible temperature raise	θuP	°C	59.2	59.2
27	Heat exchange surface area	Aca	m²	2.9000	2.9000
28	Heat exchange coeffcient	kca	kW/m²°	0.0276	0.0276
29	Heat exchange flow	Qab	kW	4.738	4.738
30	Total power loss	PV	kW	4.609	4.609
31	Safety factor thermal overload	ST	--	1.03	1.03
32	7. Calculation contact stress	Symbol	Unit	Worm	Wheel
33	Elasticity factor	ZE	/N/mm	152.50	152.50
34	Worm diameter ratio	d1/a	--	0.33	--
35	Contact factor	Zρ	--	2.979	2.979
36	Calculated contact stress	σH	N/mm²	--	241.8
37	Effective service life	Lhc	h	--	25000
38	Life factor	Zh	--	--	1.000
39	Load cycles factor	Zn	--	--	0.805
40	Endurance contact stress	σHlim	N/mm²	--	733
41	Permissible contact stress	σHP	N/mm²	--	590
42	Safety factor contact stress	SH	--	--	2.44
43	8. Calculation wear stress	Symbol	Unit	Worm	Wheel
44	Projected tooth face area worm	Ap2	mm²	--	1280
45	Tooth wear surface area wheel	Az2	mm²	--	1372
46	Wear loss limit in mass	Dmlim	kg	--	0.100
47	Number of load cycles	NL	Mcy	--	56.250
48	Wear endurance stress	σWlim	N/mm²	--	82.5
49	Wear roughness factor	WR	--	--	0.99
50	Wear friction velocity	vg1	m/s	--	6.59
51	Wear velocity factor	Wv	--	--	3.14
52	Permissible wear stress	σWP	N/mm²	--	281.2
53	Safety factor wear on wheel	SW	--	--	1.16
54	9. Calculation tooth root strength	Symbol	Unit	Worm	Wheel
55	Face width at tooth root	b2	mm	--	70.00
56	Transverse tangential force	Ft2	kN	--	21.237
57	Calculated tooth root stress	σF	N/mm²	--	29.1
58	Alternating load factor	YA	--	--	1.00
59	Endurance tooth root stress	σFlim	N/mm²	--	225.0
60	Permissible tooth root stress	σFP	N/mm²	--	225.0
61	Safety factor tooth root strength	SF	--	--	7.73
62	10. Calcul worm shaft deflection	Symbol	Unit	Worm	Wheel
63	Area moment worm shaft	I1	mm^4	2352140	--
64	Calculated deflection worm shaft	fm	mm	0.035	--
65	Permissible deflection worm shaft	fmP	mm	0.042	--
66	Safety fact worm shaft deflection	Sd	--	1.21	--