How to remove Date Hierarchy

Perfect!  Thank you Ashish_Mathur for your response.

Just to summarize for anyone who may come across this same issue...
My goal was to calculate sales per week.  I was able to calculate sales per week using the following formula:

WeeklySales = SUMX('orderDetails',[quantitySold] * [priceEach] ) // row-by-row sales

This line of code generates row-by-row sales however it does not sum the sales for each week.  In order to sum sales for each week, I need to define a week.  This is where the WEEKNUM() function is used. 

The challenges that I had were that 1) My data was imported as a hierarchy and 2) I was using WEEKNUM() within a measure therefore the date hierarchy was passed as an argument.  Using Ashish_Mathur suggestion to create a calculated column the entire date (not hierarchy) is passed as an argument.

At a minimum create a calculated column like this:

OrderWeekNo = WEEKNUM([orderDate])    // add this as calculated column, NOT MEASURE
                                                                      // Select the column and "Don't Summarize" in the
                                                                      // summarize option otherwise it returns 1 number.
                                                                      // DO NOT convert this new column to a date.  Use Integer

However if you use this simple formula then weeks are aggregated for each year.  For example week 1 sum would be the sum of each week 1 from 2003 + 2004 + 2005.... This can be helpful if you want to understand the sum of performance for week 1 for each year.  It's not what I wanted because I wanted to see a nice visual line chart with performance for each week.

Using the measure and column code I was able to modify in the visual itself by adding the  year from the hierarchy ([orderDate].[year]), OrderWeekNo, and then product of the quantityOrdered and priceEach columns to the visual.  This allowed me to separate the calculated $$ by the week number and keep each year separate without converting dates to strings.
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