Options for Control of Gaps and Clearances

The general rule is (as already mentioned in the specification of the input language above) that the gaps may be defined in one of the following ways:

• By an explicit value

• By a radius with a given offset

• By leaving it undefined. This is interpreted as 0.

Moreover, certain clearances may be overridden by input.

Special options are:

1. For certain combinations of cutouts and profile types the clearances C1/C3 and C5/C7 are not independent of each other. (However, for profiles without flange on the moulded side C1=C3 and for flat bars C5=C7).

   The following rules are applied (in the given order):

   • If C1=-1 then calculate C1 from C3.

   • If C3=-1 then calculate C3 from C1.

   • In cutouts which are open (without lug) on the mould line side C3 will be used for T bars, C1 for all other profile types.

   • Regarding C5 and C7 the following rules hold (applied in the specified order):

     • If C7=-1 then calculate C7 from C5.

     • If C5=-1 then calculate C5 from C7.

     • In cutouts which are open (without lug) on the non-mould line side C7 will be used as given for flat bars, recalculated from C5 for all other profile types, even if explicitly given.

2. For bulb bars, the cutout control offers two ways of interpreting C5, see the attribute /BULB_CLEARANCE in the input specification.

3. For asymmetrical T-bars (type 35) C3 is normally measured from the leftmost edge of the flange.

   Option /SKIP_OVERSHOOT makes C3 be measured from the web of the profile instead, cf. the figure below.

   

   Figure 2:9. Options for C3 for asymmetric T profiles (type 35).

4. In a similar way /SKIP_OVERSHOOT for a profile of type 36 will make C4 be measured from the upper edge of the flange. Otherwise C4 is measured from the top of the web.

   

   Figure 2:10. Options for C4 for profile type 36.

5. For cutouts with a lug on one side and quite open on the other, giving option /FL_WIDTH means that these clearances are set to B -S +<xxx>. (Here, B is the width of the flange and S the thickness of the web and <xxx> the given value).

   This will normally result in a cutout with total width between the lug and the opposite side equal to B+<xxx>. It is especially useful when T-bars should be inserted as described in the figure below and should be used only for cutouts with lug one side. This option is valid for C1 and C7.

   

   Figure 2:11. Clearance depending on flange width.

6. Similarly, the option /OPPOSITE means that the distance <xxx> should be measured from the opposite side of the web normally applicable for C1 and C7.

   However, the same technique can be used to calculate C6 according to the figure below, and C2 as in Figure 2:13 below.

   

   Figure 2:12. Clearance measured from upper flange surface.

7. If C2 is defined for profile types where the flange is not extending into the mould line side of the profile this inhibits the direct connection between R3 and R4 in main types 10, 11, 19, 20, 21 and 39.

   The clearance between the starting point of R2 and the lower flange surface is supposed to be C2 (with a possibility to calculate if from the upper surface by adding option /OPPOSITE) as shown in the figure below.

   

   Figure 2:13. Options for control of C2