Hi rohit..
hope this piece of code helps you out .
''to reset the default comparison operator
UltraGrid1.DisplayLayout.Bands(0).Columns("Your Column").FilterOperatorDefaultValue = FilterOperatorDefaultValue.Default
''to reset the default comparison type
''this is for reseting logical operator.
UltraGrid1.DisplayLayout.Rows.ColumnFilters.ResetLogicalOperator()