DVS 1612

List of Classification Parameters

Evaluation Distance: Reference distance to find the evaluation location from the weld element at which the stress values are extracted.
Weld Width: Width of the weld material from the web wall. This parameter is ignored if specifying the evaluation distance is done manually.
Note: Refer to - Find Evaluation Positions.
Cutoff Value: Used along with the material yield to determine the cutoff yield value to be used.
Yield (cutoff) = Material yield / Cutoff value
Groove Gap (b): Gap between the two plates at the location of the weld. b in the above image.
Groove Depth (h): Height of the groove from the top, calculated as t-c from the above image.
Groove Angle (alpha - deg): Angle of the groove/plate walls at the location of weld. α in the above image. Refer the image below for the groove parameters.
Notch Class - Transverse Location_X: Notch class definition considered for the fatigue limit calculation for the normal stress component in the transverse direction (perpendicular to the axis of the weld) at ‘X’.
Note: Where ‘X’ can be any evaluation location.
Notch Class - Longitudinal Location_X:: Notch class definition considered for the fatigue limit calculation for the normal stress component in the longitudinal direction (parallel to the axis of the weld) at ‘X’.
Notch Class - Shear Location_X: Notch class definition considered for the shear stress component at ‘X’.
Intermittent Factor Location_X: This factor is used indicate the partiality of welds. This ratio describes the length of the weld that has actually been welded.
Thickness Influence Location_X (TI): Thickness influence represents the resultant maximum weld thickness. It varies based on the weld type, and is used in the calculation of effective weld thickness (A) in the equation below. This parameter is location specific.
Thickness Flag Location_X: Indicates which shell thickness you need for the calculation of effective weld thickness (A). Valid options are T and Tmin. Also location specific. T = thickness of welded shell. Tmin = min thickness of all connected shells.
Effective Weld Thickness (A) = Thickness based on the Thickness Flag (TF) X Thickness Influence (TI)
Material Grade - Location_X: Grade of shell material used. Options – S355, S235. Also, interpolation for in between values is supported. Location specific.
Material Yield - Location_X: Material yield. Location specific.

Frequently Asked Questions

What is the Cutoff Parameter?

It is a safety factor to be used along the yield strength. This value is used to determine the upper limit for the fatigue strength.

Fatigue strength (cutoff) = Material yield / Cutoff value

What is the Intermittent Factor?

This factor is used to indicate the partiality of welds. This ratio describes the length of the weld that has actually been welded. Whenever the weld connection at any particular location is not continuous/complete, then you are suggested to modify/reduce this parameter to take into account the reduced weld material.

Details about stress correction?

The stress value correction is carried as shown in the formula below:

σ_{T} (c o r r e c t e d) = \frac{σ_{T} \cdot (\frac{t}{A r})}{Z}

Where:

$σ_{T}$ - Stress value before correction (extraction from element at evaluation location).
$t$ - Thickness of the shell at the evaluation location.
$A r$ - Effective weld thickness
$Z$ - Intermittent factor

How does the exponent x interpolation work?

In case of DVS 1612, the value of exponent ‘x’ depends on the material grade and has different values based on the grades of S235 and S355. But, whenever the base/web material does not fall into either of these grades, then the tool uses an interpolation technique to find the intermediate ‘x’ exponent value.

The process of interpolation is as follows:

The tool retrieves the material grade/yield assigned for the particular location from the classification area.
The tool also identifies the fatigue class/notch case for the particular location from the classification area.
Based on this fatigue class, the tool retrieves both the values of exponent 'x' from the “regulation_ data” folder belonging to the grades S235 and S355.
An initial check is carried out to determine if the material yield is higher than the highest grade (S355) or if it is lower than the lowest grade. If so, then the tool considers the exponent 'x' to belong to the highest/lowest grade respectively for calculation.
If the material yield value is in between the two grades, then the tool calculates the intermediate value of exponent ‘x’ using a linear interpolation technique. The calculated value of exponent ‘x’ is then used for utilization calculation.