7 Interference fit according to DIN 7190

The interference fit is a frictional shaft-hub-connection. The joint pressure in the friction surfaces $pF$ , that is necessary for the power transmission, is generated by the deformation of shaft and hub. According to the manufacturing method, you have to differentiate between a shrink and force fit. Shrink-fitting is a procedure in which heat is used to produce a very strong joint between two pieces of metal, one of which is inserted into the other. Heating causes one piece of metal to contract or expand on to the other, producing interference and pressure which holds the two pieces together. In a force fit of cylindrical parts, the inner member has a greater diameter than the hole of the outer member. The calculation takes place according to DIN 7190 for cylindrical interference fits. In addition to it, the influence of the centrifugal force, the stepped hub geometry, torque, radial force and bending moment are considered as well.

7.2 Application

The standard DIN 7190 defines the calculating basis for interference fits with cylindrical surfaces whose parts are made of metallic materials. This standard applies mainly for the common mechanical engineering but can be used also in other fields (e.g., precision engineering). The calculation method DIN 7190 applies for interference fits with a constant axial length of inner and outer part (see figure 1). The calculation can be used approximately for interference fits according to figure 2. Stress increases in the area of the hub edge are not considered.

7.3 Selection of fit/tolerances

For a comfortable selection and calculation of possible tolerances, a dialog window for the selection of fits is included. This dialog window contains the tolerance system according to DIN ISO 286 including all IT classes. In DIN ISO 286, the tolerances for the diameter are defined up to 500 mm. The desired tolerance field can be selected for hub and shaft from a listbox. An individual input of the upper and lower deviation is also possible. The lowest and highest interference as well as the fit type for the nominal diameter will be displayed. For the calculation of possible fits, the IT scope can be selected. The following IT scopes are available:

To find the right fit, different options are available (see section 7.16.3 ‘Selection of fit / Calculation of possible fits’). Based on the specified loads, the minimum and maximum interference are determined. These values will be displayed automatically in the field ‘Calculation of possible fits’ and provide the basis for the dimensioning and selection of appropriate tolerances. In addition, there is the possibility to define a tolerance field for the hub and shaft. Select the option ‘Show only preferred fits’ and click the button ‘Search fits’ and all possible fits will be displayed. Then choose one of the fits.

7.4 The dimensioning

In addition to the possibility to get suggestions for the appropriate fits, further dimensioning functions for the joint diameter, the length, the torque and the axial force are available. In section 7.16.3 you can find an example for the dimensioning of the torque.

7.5 The influence of the centrifugal force

The influence of the centrifugal force on the interference fit by the input of a speed is considered according to F. G. Kollmann´s, Braunschweig ‘Rotierende Pressverbände bei rein elastischer Beanspruchung’ (Konstruktion 33, 1981 H.6, pp.233-239).

7.6 Additional external loads

In addition to the consideration of axial and tangential forces, a radial and a bending moment can be specified. The calculation takes place according to Prof. Gropp ‘Das Übertragungsverhalten dynamisch belasteter Pressverbindungen ...’ and Prof. Hartmann ‘Berechnung und Auslegung elastischer Pressverbindungen’. Resulting from the given loads for the bending moment and radial force, the additional external loads may be determined from the following equations:

For a too small minimum joint compression, the hub lifts-off and a so-called gaping joint occurs. A gaping joint minimizes the joining surface available for the power transmission and is imperative to avoid.

If this condition is not fulfilled, then an appropriate warning/message appears.

7.7 The operating factor (application factor)

The operating factor (application factor) is determined for the calculation of the operating torque $Tb$ similarly to the gear calculation according to DIN 3990 with the following table.


Application factors $KA$ according to DIN 3990-1: 1987-12

Working characteristics	Working characteristics of the driven machine

of the driving machine	Uniform	Light shocks	Moderate shocks	Heavy shocks

Uniform	1,0	1,25	1,5	1,75

Light shocks	1,1	1,35	1,6	1,85

Moderate shocks	1,25	1,5	1,75	2,0

Heavy shocks	1,5	1,75	2,0	2,25 or higher


Examples for driving machines with various working characteristics
according to DIN 3990-1: 1987-12

Working characteristics	Driving machine

Uniform	Electric motor (e.g., d.c. motor), steam or gas turbine with uniform operation¹ (small rarely occurring starting torques)

Light shocks	Steam turbine, gas turbine, hydraulic motor or electric motor (large, frequently occurring starting torques)

Moderate shocks	Multiple-cylinder internal combustion engines

Heavy shocks	Single-cylinder internal combustion engines

¹ Based on vibration tests or on experiences gained from similar installations.


Examples of working characteristics of driven machines
according to DIN 3990-1: 1987-12

Working characteristics	Driven machines

Uniform	Steady load current generator; uniformly loaded conveyor belt or platform conveyor; worm conveyor; light lifts; packing machinery; feed drives for machine tools; ventilators; lightweight centrifuges; centrifugal pumps; agitators and mixers for light liquids or uniform density materials; shears; presses; stamping machines¹; vertical gears; running gear².

Light shocks	Non-uniformly (e.g., with piece or batched components) loaded conveyor belts or platform conveyors; machine tool main drives; heavy lifts; crane slewing gear; industrial and mine ventilator; heavy centrifuges; centrifugal pumps; agitators and mixers for viscous liquids or substances of non-uniform density, multi-cylinder piston pumps, distribution pumps; extruders (general); calendars; rotary kilns; rolling mill stands³ (continuous zinc and aluminum strip mills, wire and bar mills).

Moderate shocks	Rubber extruders; continuously operating mixers for rubber and plastisc; ball mills (light); woodworking machine (gang saw, lathes); billet rolling mills³,⁴; lifting gear; single-cylinder piston pumps.

Heavy shocks	Excavator (bucket wheel drives), bucket chain drives; sieve drives; power shovels; ball mills (heavy); rubber kneaders; crushers (stone, ore); foundry machines; heavy distribution pumps; rotary drills; brick presses; debarking mills; peeling machines; cold strip³,⁵; briquette presses; breaker mills.

¹ Nominal torque: maximum cutting, pressing or stamping torque.
² Nominal torque: maximum starting torque.
³ Nominal torque: maximum rolling torque.
⁴ Torque from current limitation.
⁵ $KA$ up to 2,0 because of frequent strip cracking.

7.8 The coefficients of friction

The following table provides some approximate values for the coefficients of adhesion/coefficients of friction for shrink fits according to DIN 7190. The values are on the safe side and can be used for sliding in circumferential and longitudinal direction.


Coefficients of adhesion for shrink fits in
longitudinal and circumferential direction during sliding

Mating of material, lubrication, joining	Coefficients of adhesion $νR,νrl,νu$

Steel/Steel pair

Pressurized oil assembly normally joined with mineral oil	0,12
Pressurized oil assembly with degreased surfaces joined with glycerine	0,18
Shrink fit normally after heating the outer part up to 300^∘C in an electric kiln	0,14
Shrink fit with degreased surfaces after heating up to 300^∘C in an electric kiln	0.20

Steel/Cast iron pair

Pressurized oil assembly normally joined with mineral oil	0,10
Pressurized oil assembly with degreased surfaces	0,16

Steel/MgAl pair, dry	0,10 to 0,25

Steel/CuZn pair, dry	0,17 to 0,25

The following table specifies the coefficients of adhesion/coefficients of friction for force fits according to DIN 7190. These values are valid for monotonic loading and are determined for inner parts made of X 210 Cr W12. They are valid for steel. After joining, the interference fits require sufficient time (24 hours is best) before first loading to assure a strong joint.

Coefficients of adhesion for force fits during monotonic loading

¹ Coefficients of adhesion are unknown




Materials			Coefficients of adhesion

old	new		dry		lubricated

		Number	$ν ll$	$ν rl$	$ν ll$	$ν rl$

St 60-2	E 335	1.0060	0,11	0,08	0,08	0,07

GS-60	GE 300	1.0558	0,11	0,08	0,08	0,07

RSt37-2	S 235JRG2	1.0038	0,10	0,09	0,07	0,06

GG-25	EN-GJL-250	0,6025	0,12	0,11	0,06	0,05

GGG-60	EN-GJS-600-3	0,7060	0,10	0,09	0,06	0,05

G-AlSi12 (Cu)	EN AB-44000 ff.		0,07	0,06	0,05	0,04

G-CuPb10Sn	CB495K	2.1176.01	0,07	0,06	-¹	-¹
G-CuSn10Pb10

TiAl6V4	TiAl6V4	3.7165.10	-¹	-¹	0,05	-¹

The coefficients of adhesive friction/coefficients of friction are dependent upon the following factors:

Due to the friction within the joint, the coefficients of adhesive friction are subject to statistical fluctuations. Therefore, the defined coefficients of adhesive friction are approximate values and are on the safe side. The values can be replaced by an experimental determination of values according to DIN 7190.

7.9 The stepped hub geometry

For the stepped hub or/and shaft (see figure below), there is a larger joint compression on the thick-walled segment than on the thin-walled segment for the same fit. Hence, widely different stress and deformation ratios occur on each segment. In that case, the total length $L F$ has to be used. The hub can be considered as composed of separate discs of different diameters. From it, the mean joint pressure for the interference fit is determined. Because the stresses and deformation cannot change abruptly from one segment to another segment, this method of segmentation presents an approximation. The effort to define the matching conditions or to determine the joint compression by using FEM calculation is just useful for critical cases.

The calculation is determined according to the algorithm in Prof. Hartmann´s ‘Berechnung und Auslegung elastischer Pressverbindungen’. Click on the button ‘stepped’ next to the input field ‘Outer diameter hub’ to consider the stepped hub geometry. Any number of segments can be defined. The section 7.16.7 ‘The stepped hub geometry’ discusses this issue. The figure shows how the segmentation has be specified. A segment can contain a constant outer hub diameter and inner shaft diameter. If a shaft bore extends over two outer hub diameters of different size, then two segments has to be defined with a different outer hub diameter and equal inner shaft diameter. In case there is a stepped shaft bore within a constant hub outer diameter, then use this method, too (a definition of two segments with equal outer hub diameter and different inner shaft diameter).

7.10 The subsidence/the surface smoothing

Due to the smoothness of asperity peaks during the joining, only the interference $Uw$ is available. Unless there are experimental values, the equations according to DIN 7190 for force and shrink fits are:

where $s$ is the subsidence that results from the determined surface roughness $Rz$ of inner and outer part. $Uo$ is the mean, lowest and highest interference. If the values of the surface roughness for the arithmetic mean value of the profile coordinates $Ra$ (formerly the arithmetical mean deviation of the roughness profile $Ra$ ) are specified according to DIN EN ISO 4287, then the determined mean values according to DIN 7190 can be used for the surface roughness $Rz$ (see table below). Select the entry ‘User defined’ from the listbox ‘Surface’. Now the input field next to the listbox is enabled and you can enter a value for the surface roughness $Rz$ .


Comparison of arithmetical mean deviation of the roughness
profile $R a$ with average surface roughness $R z$

$Ra$ in $μm$		Ra0,8	Ra1,6	Ra3,2

$Rz$ in $μm$	from	3,15	6,3	12,5

	to	10	20	31,5

Averaged surface roughness $Rz$ in $μm$		Rz6,3	Rz12,5	Rz20

7.11 The modification of diameter

The calculation of the modification of diameter at the inner and outer diameter of shaft and hub takes place according to Niemann´s ‘Maschinenelemente’ volume 1 pp.789, 3rd edition 2001. There, the modification of the diameter is considered by the joint pressure and centrifugal force. The influence of temperature on the modification of diameter is considered on the outer diameter of the shaft and on the inner diameter of the hub by the modified interference and joint pressure.

7.12 The menu item ‘Options’

The button ‘Options’ allows you to define the minimum safeties, the mating clearance, the temperatures at joining (room temperature and shaft temperature) as well as the coefficient of friction at joining for pressing in and pressing out for a force fit. Additionally, there is the possibility to enter the number of decimal places for the output of the numerical values in the report (see section 7.16.8 ‘The button Options’).

7.13 Fretting corrosion

According to Niemann ‘Maschinenelemente’ volume 1 p.800, 3rd edition 2001, the torque is transmitted also during repeated load by elastic transformation (i.e., without slip), if the torque $T$ is smaller than the maximum torque $TE$ . For a solid shaft, disk-shaped hub with $LF ∕DF > 0,25$ and shaft and hub with equal E modulus, it is expressed as:

$T⋅Sr$ is the slipping torque against fretting corrosion. This results in remedial measures agaisnt fretting corrosion. The joint pressure, coefficient of adhesion in terms of circumference, the joint diameter or the safety against sliding can be increased in order to avoid micro sliding/fretting corrosion. A rotating bending may cause fretting corrosion. If the mentioned conditions for a possible determination of the maximum torque are given, the maximum torque is calculated for the minimum, mean and maximum interference.

7.14 Assembly and disassembly

Shrink fits: In shrink fits, the outer member is heated or the inner part is cooled, or both, as required. The calculation of the temperatures to cool the inner part or to heat the outer part is dependent upon the chosen minimum fit. Additionally, a mating clearance for joining has to be kept to avoid adhesion. For an individual production, it is recommended to use the following mating clearance

For the individual production the risk of premature adhesion of the joining parts is covered before the assembly process is completed. By using joining devices, the above recommended mating clearance can be fallen below. Click on the button ‘Options’ to define the mating clearance (see section 7.16.8 ‘The button Options’). Two possibilities are available. On the one hand, the mating clearance can be specified dependent upon the joint diameter, on the other hand a mating clearance can be entered directly in $μm$ . In general, the room temperature as well the joint temperature of the inner part are set. The required joint temperature is calculated as follows:

The button ‘Options’ allows to change the room temperature and the joint temperature of the shaft (see section 7.16.8 ‘The button Options’). The highest joint temperature may not exceed the required work piece features of the heat-treated parts. In the following table, the data according DIN 7190 valid data are specified for the maximum joint temperatures dependent on the material of the outer part and the heat treatment.


Joint temperature

Material of the outer part (hub)	Joint temperature ^∘C maximum

Structural steel lower strength
Cast steel	350
Modular cast iron

Hardened and tempered steel or cast steel	300

Surface layer hardened steel	250

Case-hardened steel or high-tempered structural steel	200

The following table provides the coefficients of linear thermal expansion for inner and outer part.


Poisson´s ratio, elastic modulus, coefficient of linear thermal expansion

Materials	Material	Poisson´s	Elastic modulus	Coefficient of linear
	No.	ratio	$N ∕mm2$	thermal expansion $α$
		$ν$	$≈$	$-6 1∘0C--$
		$≈$		Heating $≈$ Supercool

MgAl8Zn	3.5812	0,3
AlMgSi	3.2315	0,34	65 000 to 75 000	23	-18
AlCuMg	3.1325	0,33 to 0,34

GG-10¹	0.6010		70 000
GG-15¹	0.6015	0,24	80 000	10	-8

GG-20¹	0.6020		105 000
GG-25¹	0.6025	0,24 to 0,26	130 000

GGG-50	0.7050	0,28 to 0,29	140 000	10	-10

Malleable cast iron		0.25	$>$ 90 000 to 100 000	10	-8

C-steel low alloyed		0,3 to 0,31
Ni-steel		0,31	200 000 to 235 000	11	-8,5

Bronze		0,35		16	-14

Red brass		0,35 to 0,36	80 000 to 85 0000	17	-15

CuZn39Pb3	2.0401	0,37
CuZn37	2.0321	0,36		18	-16

¹ Not allowed for system engineering in metallurgy/rolling mills

Liquid nitrogen $(ϑI = - 195,8∘C)$ is used to cool shrink fits. Liquid nitrogen shrink fitting is one of the safest assembly methods. In some cases $CO2$ dry ice $(ϑI = - 78,4∘C)$ is also used as a coolant. Based on the maximally permissable temperature of the hub, it must be decided whether the cooling process is necessary or not.

The ‘Option’ button allows to define the coefficients of adhesion $ν ll$ for pressing in and pressing out (see also section 7.16.8 ‘The button Options’). The table (see table 7.8) specifies the coefficient of adhesion $ν ll$ . The maximum joint pressure $p max$ is determined for the highest interference. In case the joining surfaces are not lubricated with grease, larger coefficients of friction and larger longitudinal and tangential forces occur. There is a risk of scuffing for joining surfaces that are not lubricated, in particular for a elastic-plastic dimensioning. Before joining, the joining surfaces should be lubricated with oil.

Furthermore, the following information has to be considered for the engineering design according to DIN 7190:

The values for the edge length $le$ are specified in the following table. The measurement is indicated in mm.


The edge length $le$

$D F$			$D F$
over	to	$le$	over	to	$le$

50	80	4	400	630	8

80	160	5	630	800	9

160	250	6	800	1000	10

250	400	7	1000	-	10

During the manufacturing process of interference fits by force fitting, the joining area is provided with a thin oil film over the entire surface. A jamming of the assembled parts must be avoided. The slip-stick effect can be avoided by the press-in speed and discharge speed of approx. 50 mm/s and sufficient pressing force (2,5x extraction force). Force fits requires sufficient time (24 hours) before first loading, then the complete adhesive force is reached (only 70% immediately after pressing).

7.15 Example of interference fits

The following section gives some guidance on selecting fits according to E. & K. Felber. There are features that can be expected in general during the assembly. The assembly rules specify the character of the fit and all features correspond to the mean value of fits. The list contains fits that are used frequently. Almost all fits can be formed in quality (e.g., from H8/u8 to H8/u7 to H6/u6). In general, the standard fits (e.g., H8/u7) can be used. According to the function, you have to select fine qualities (e.g., H6/u6) for larger requirements (requirements for accuracy and uniformity). The following examples are taken from the mechanical engineering and cannot to be considered as complete in any detail.

Features, assembly rule: The parts are assembled and tightened and have a strong interference. The parts are pressed together or assembled into position while hot and cooled. In general, a safety device against torsion or shifting in lengthwise direction is not necessary.

Examples: Spur gears that are mounted tightly on a shaft, couplings, collar rings, press rings, wheel rims, bearing bushings in housings, bushings in gear hubs, tight pivots, bushings made of synthetic resin pressed material, parts which cannot be loosened by large forces.

7.16 Example: Interference fit calculation according to DIN 7190

Our calculation example shall support you with a fast start into the interference fit calculation module with its numerous possibilities. Let´s take a look at the follwing example.

7.16.1 Start the calculation module

Please login with your user name and your password. Select the module through the tree structure of the Project Manager by double-clicking on the module or clicking on the button ‘New calculation’.

7.16.2 The input values

A cylindrical interference fit has to be dimensioned against sliding. Enter the following values into the appropriate input fields:

7.16.3 The calculation

Please enter the values into the input fields. When you enter your data, the results are determined and displayed immediately in the result panel. During the input of the values it can happen that the results will be marked in red. Nevertheless please continue to input the data as usual.

Please note: Please note the section ‘Selection of fit’ for the specification of the tolerances. With the definition of the surface quality of the hub, you have to notice that the given value (Rz=6) has to be entered by the ‘User defined’ input. Select ‘User defined’ in the appropriate listbox and enter the desired value into the input field next to the listbox.

Please note: Change the unit of measurement

If you right-click into an input field, then you can change the unit of measurement very easily.

1. Just a right-click on the input field where you want to change the unit.

A context menu is opened. You will get a survey of all units which are available. The two arrows mark the current setting.

2. Select a unit.

With the modification of the measurement, the description of the input field changes. The current value will be converted into the appropriate unit of measurement.

Selection of fit / Calculation of possible fits

The button ‘Selection’ allows you to open the dialog window for selection of fits. Here you can choose the possible tolerances or the appropriate fits can be suggested.

You will find the tolerance system according to DIN ISO 286 with all IT classes. On the top of the dialog window, you can select easily the tolerance field for the shaft and hub via listboxes.

For the selected tolerance the upper deviation and the lower deviation for shaft and hub will be displayed. Furthermore the specification of the fit type as well as the highest and lowest interference occurs.

All deviations for the shaft and hub can be entered directly. You have to select the option ‘Activate input of user defined tolerances’.

For the dimensioning of a fit you have got different possiblities. In the following we describe these possibilities for you. In our example we will explain, how you can find the right fit with the calculation of possible fits.

The selection of fits based on the calculation example

The dimensioning of the maximum torque

Due to the fit calculation, a safety close to the given minimum safety has been determined. By the help of the comfortable dimensioning functions, other values can be checked and optimized regarding the use of the minimum safety. So the maximum torque can be defined using the given minimum safety against sliding $(SR=1.2)$ . The button ‘Options’ allows you to specify the minimum safety (see section 7.16.8 ‘The button Options’). Click on the dimensioning button (‘calculator symbol’) next to the input field for the torque.

Here the maximum torque is ‘83.60 Nm’. If you enter now a higher value than ‘83.60 Nm’, the safety against sliding is fallen below.

The result panel is marked in red. You also get an appropriate information in the message window.

Now click on the calculator symbol again, then the maximum torque is determined (83.50 Nm) and the minimum safety of ‘1.2’ is fulfilled. The specifications of the results is given for the mean, highest, and lowest interference. If the minimum safety is not fulfilled, then the safety is marked in red.

The ‘Redo’ and ‘Undo’ button

The button ‘Undo’ allows you to reset your input to an older state. The button ‘Redo’ reverses the undo.

The material selection

Select the material and the roughness from the material selection. Use the entry ‘User defined’ to specify your individual material.

In case you need further information on the corresponding material, easily click on the button ‘Material’. This applies for the shaft as well as for the hub.

The message window

The calculation module contains a message window. You will find a message window in all calculation modules where you will get some hints, messages, or warnings. You will find all information and hints, which are displayed in the message window, in the calculation report later.

The quick info line

Move the mouse pointer to an input field or a button, then you will get some additional information. This information will be displayed in the quick info line.

7.16.4 The results

The specification of the results is displayed for the mean, minimum, and maximum interference of the fit. In case a minimum safety is not fulfilled, the result will then be marked in red. After the value was taken over, the results will be determined and displayed.

7.16.5 The documentation: The calculation report

In case you have finished your calculation, please click on the button ‘Report’.

The calculation report contains a table of contents. You can navigate through the report via the table of contents that provides links to the input values, results and figures. The report is available in HTML and PDF format. Calculation reports, saved in HTML format, can be opened in a web browser or in Word for Windows.

7.16.6 How to save the calculation

After accomplishing your calculation, save the calculation either on the eAssistant server or on your workstation locally. Click on the button ‘Save’.

If you have activated the option ‘Enable file save local’ in the Project Manager and the option ‘Local’ in the calculation module, a standard Windows dialog for saving the file on your workstation appears.

Please note: You must not forget that the calculation module has to be closed to activate the option ‘Enable file save local.’

In case you have not activated this option, a new window is opened and you can save the calculation on the eAssistant server (find further information in the chapter ‘The general functions’).

Please enter a name into the input field ‘Filename’ and click on the button ‘Save’. Then click on the button ‘Refresh’ in the Project Manager. Your saved calculation file is displayed in the window ‘File’.

7.16.7 The stepped hub geometry

Here you can define the geometry for the hub with a varying outer diameter and a varying shaft hole. Click on the button ‘stepped’ next to the input field ‘Outer diameter hub’.

Define here the several hub segments. Enter the number of hub segments, the lengths of segments, the outer diameter of the hub as well as the inner diameter of the shaft.

The diagram is opened. That diagram shows the compressive stress along the length of the press fit.

The current values can be selected and displayed using the mouse pointer. On the basis of the minimum, mean and maximum interference, all values for the minimum (pk), mean (p) and maximum (pG) compressive stress will be represented.

7.16.8 The button ‘Options’

The button ‘Options’ allows you to define the minimum safeties, the mating clearance, the temperature at joining (room temperature and shaft temperature) as well as the coefficients of friction at joining for pressing in and pressing out for a force fit. Additionally, there is the possibility to enter the number of decimal places for the output of the numerical values in the report. Click on the button ‘Options’.

Our manual is improved continually. Of course we are always interested in your opinion, so we would like to know what you think. We appreciate your feedback and we are looking for ideas, suggestions or criticism. If you have anything to say or if you have any questions, please let us know via telephone +49 (0) 531 129 399-0 or email eAssistant@gwj.de.

Chapter 7
Interference fit according to DIN 7190

7.1 General information

7.2 Application

7.3 Selection of fit/tolerances

7.4 The dimensioning

7.5 The influence of the centrifugal force

7.6 Additional external loads

7.7 The operating factor (application factor)

7.8 The coefficients of friction

7.9 The stepped hub geometry

7.10 The subsidence/the surface smoothing

7.11 The modification of diameter

7.12 The menu item ‘Options’

7.13 Fretting corrosion

7.14 Assembly and disassembly

7.15 Example of interference fits

7.16 Example: Interference fit calculation according to DIN 7190

7.16.1 Start the calculation module

7.16.2 The input values

7.16.3 The calculation

Please note: Change the unit of measurement

Selection of fit / Calculation of possible fits

The selection of fits based on the calculation example

The dimensioning of the maximum torque

The ‘Redo’ and ‘Undo’ button

The material selection

The message window

The quick info line

7.16.4 The results

7.16.5 The documentation: The calculation report

7.16.6 How to save the calculation

7.16.7 The stepped hub geometry

7.16.8 The button ‘Options’

Chapter 7Interference fit according to DIN 7190

7.1 General information

7.2 Application

7.3 Selection of fit/tolerances

7.4 The dimensioning

7.5 The influence of the centrifugal force

7.6 Additional external loads

7.7 The operating factor (application factor)

7.8 The coefficients of friction

7.9 The stepped hub geometry

7.10 The subsidence/the surface smoothing

7.11 The modification of diameter

7.12 The menu item ‘Options’

7.13 Fretting corrosion

7.14 Assembly and disassembly

7.15 Example of interference fits

7.16 Example: Interference fit calculation according to DIN 7190

7.16.1 Start the calculation module

7.16.2 The input values

7.16.3 The calculation

Please note: Change the unit of measurement

Selection of fit / Calculation of possible fits

The selection of fits based on the calculation example

The dimensioning of the maximum torque

The ‘Redo’ and ‘Undo’ button

The material selection

The message window

The quick info line

7.16.4 The results

7.16.5 The documentation: The calculation report

7.16.6 How to save the calculation

7.16.7 The stepped hub geometry

7.16.8 The button ‘Options’

Chapter 7
Interference fit according to DIN 7190