SELECT WelderIdAscii =
	CASE 
	WHEN len(WelderId) = 2 THEN ( ASCII(WelderId) * 10000 ) + ( ASCII(SUBSTRING(WelderId,2,1) ) )
	WHEN len(WelderId) = 3 THEN ( ASCII(WelderId) * 10000 ) + ( ASCII(SUBSTRING(WelderId,2,1) ) * 100 ) + ( ASCII(SUBSTRING(WelderId,3,1) ) )
	END,
WelderId
FROM #letters
ORDER BY WelderIdAscii DESC