Details about Standard Hole Types
- Last UpdatedDec 01, 2025
- 3 minute read
The available standard holes are described in detail below.
Circular hole (D)
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Designation: |
D <d> |
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Example: Turning angle is irrelevant. |
D250 |
Symmetrical Manhole ("Oval Hole") (HO)
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Designation: |
HO <a> * <b> (a>b) |
|
Example: |
HO600*400 |
Asymmetrical Manhole (HOR)
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Designation: |
HOR <a> *< r1 >*< r2> |
|
Example: |
HOR600*200*100 |
Elliptical Hole (HE)
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Designation: |
HE <a> *<b> |
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Example: |
HE250*125 |
Superelliptical Hole (HSE)
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Designation: |
HSE <a> *<b> * <e> |
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Here e is the exponent of the "super ellipse" equation |
|
|
(x/a) ** e + (y/b) ** e = 1 |
|
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e = 2.5 |
results in a "super ellipse" |
|
e = 2 |
results in "normal" ellipse, closer to the mathematical ellipse than the HE hole |
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Example: |
HSE1200*600*2.5 |
Elliptical-Rectangular Hole (HER)
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Designation: |
HER <c> *<d> * <a> * <b> |
|
Example:¨ |
HER2100*950*1500*950 |
(This is an elliptical hole where rectangular "strips" have been inserted around the symmetry axes).
Rectangular Hole (HR)
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Designation: |
HR <a> *<b> * <r> |
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Example: |
HR1480*680*40 |
Rectangular Hole with "Mickey Mouse Ears" (HRM)
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Designation: |
HRM <a> *<b> * <r> [*<d>] |
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Example: |
HRM2000*700*50*10 |
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(If <d> is left out the corner arc passes through the sharp corner of the rectangle, that means, d=0). |
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Triangular Hole (HT)
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Designation: |
HT <a> *<b> * <r1> [*<r2>[*<r3>]] |
|
Example: |
HT600*600*75 |
If r2 and r3 are left out, r2 = r3 = r1
If only r3 is left out, r3 = r2
The reference point of this hole is in the intersection point between the lines along edges "a" and "b".