Is there a way to set bolting for different rating in one spec. Currently PDMS looks for the Bdia and number of bolts and picks the first available bolt from the spec..
Most of the time, we have different rating flanges in one spec and this results in wrong bolt lengths for some sizes as per bolt selection based independent of rating.
Any possibility to set this o how ppl r working with this.
PS: Our work around is to calculated in in between extra length an use it get the closest lengths for both rating
Use the 'New' (Its about 10 years old now)Bolting. The boltspec is not dependant upon flange ratings.
The system works out the bolts from the Boltref of the components and the Boltspec.
Component Boltrefs also allow different ratings at different p-points
Thanks for the document and info.....note that we are already using NEW method and I believe I was not able to explain the problem well....everything is working fine but the problem is getting exact bolt lengths when using different ratings flanges in one spec.
Example...lets say you have the following flanges in one spec
Now all these flanges use the same bolt diameter of 1/2" BUT different bolt lengths....
With the new bolting method, the system will pick up the first bolt with Bdia 1/2" in the spec and use its SBOL for extra length calculation and all
Though the flange thickness will be different for different ratings but as the system will only use the first available 1/2" bolt in the spec so the extra length will be used for that...now if we use the extra length for #150RF, it may give incorrect lengths for 300 and 600 and vice versa...
so to overcome this...we put an intermediate extra length and try to satisfy all conditions (three or more ratings)..most of the values can be satisfied but still some DN sizes cannot have exact values coz satisfying one rating can disturb the others...
so coming back to my question. is there a way that PDMS can select bolts from spec based on Rating and Bdia instead of just bolt dia???
The extra length is used to allow for the nut, washers, plus the runout.
The flange thickness comes from the boltset. It is not part of the sbol extra length.
The extra length for an sbol should be the same regardless of the flange rating. Bolts are not rated. A 1/2 inch dia bolt uses the same nut whether it is joining two flanges or two pieces of wood.fo
The flange thickness comes from the boltset. It is not part of the sbol extra length.
Agree with what you say...now to clarify the issue further..take this example....consider the values as arbrituary please....I know the bolt lengths are no as per standard but this sort of seneio is seen with std lengths too wic i dont remember on top pf my head..so just using dummy values.
with your method how will you define the bolts in the spec so that all these four condition are satisfied when the following flanges are in one spec and the bolts also in the same or a separate bolt spec..
Do you agree that all these flanges below will use the same bolt and nuts so now the problem and the system will pick the first bolt with Dia 1/2" in the spec for calculating the total length...so question is what extra length to use which will satisfy this sorta condition...
Also assume that the Blen of BTAB uses 5mm interval for standard lengths...i.e 50mm 55mm 60mm 65mm 70mm 75mm 80mm 85mm and so on
if you agree that this is not possible, than coming back to my question, is there a way to set bolting as per flange/bolt size and rating to pick associative bolt from the spec?
Using New Bolting The length is calculated from the BOLTSET not the SBOL.
It calculates the length first.
It then finds the corresponding sbol entry in the spec for diameter and btype.
From the sbol it gets the Dtab
From the dtab it finds the nearest length.
So you only need one entry for each diameter/type combination in the spec
i guess the only solution to get EXACT bolt lengths for different rating flanged items in one spec is via BSEL....
the problem with this is that designers have to manually select the BSEL attribute for different rating flanges in design and than spec uses that to select the correct bolting
