Only in the context of sizzlers like JLG (NYSE:JLG) or Manitowoc (NYSE:MTW) could you say that industrials like Eaton (NYSE:ETN), Emerson, and Parker-Hannifin (NYSE:PH) have underperformed. So what do you call this sector's performance? A "melt-up" seems kinda silly, and a "grease bubble" is a little too negative. Whatever the case, times are still good for Parker-Hannifin.

Sales this quarter were up another 18%-plus for Parker-Hannifin, with organic growth topping out in double digits. That's not bad when the corporate target is somewhere around 5% organic growth. What's more, this is profitable growth. Gross and operating margins expanded again, letting the company post more than 33% growth in operating income. Cash, too, continues to roll into the company's coffers and fund further acquisitions, which should in turn boost sales and cash receipts down the line.

All of the major business units did fine ... well, sort of. The industrial business had no problems here or abroad, and the aerospace business too is enjoying its late-cycle revival. With the climate-control business, though, it seems as though plant relocations and restructurings haven't quite paid off yet, so a strong revenue performance wasn't matched in the operating earnings.

I'm still enjoying some of the skepticism surrounding industrial stocks. In the case of Parker-Hannifin, for instance, a lot of analysts seemed to get really twitchy when they found out that the company's March sales were a little soft -- as though one month's performance really tells the tale. Of course, eventually we will see the end of the line, and industrial activity will slow. But trying to pin the tail on the recession donkey is more often than not going to just make you look like a jackass.

Loyal Foolish readers know I have a soft spot for industrials. I really like Danaher (NYSE:DHR), and I kinda like other conglomerates such as Tyco (NYSE:TYC) and Illinois Tool Works (NYSE:ITW). The hitch, as always, is price. I don't think Parker-Hannifin is overpriced, but rather, I just don't see it as so much of a bargain relative to those first two I mentioned. Still, as long as economic activity stays strong and management continues to execute on its improvement efforts, I wouldn't be in a rush to part from this stock.

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Fool contributor Stephen Simpson has no financial interest in any stocks mentioned (that means he's neither long nor short the shares).