This is really simple. First of all you need to pick a type and validate with case condition and then join case results together.

LTRIM(
    CASE WHEN {shiptype} IS NOT NULL THEN '|SHIP='||{shiptype} ELSE '' END ||
    CASE WHEN {packagetype} IS NOT NULL THEN '|PACKAGEID='||{packagetype} ELSE '' END ||
    CASE WHEN {othertype} IS NOT NULL THEN '|OTHER='||{othertype} ELSE '' END
, '|')

Lastly, LTRIM(Data, '|') removes the leading | . Cheers.