As they left his factory floor, a neat and orderly, 30,000-square-foot, wood- and metal-scented hall in Sonoma, Price Pump Co. president and CEO Bob Piazza said to the congressman he was showing around: "I bet you didn't know we existed."

Rep. Mike Thompson, D-St. Helena, acknowledged he hadn't.

"There are manufacturing operations throughout the Fifth Congressional District that none of us know about. You'd be astounded," Thompson said during a "Congressional Dialogue" sponsored by the National Association of Manufacturers at the 82-year-old pump company on Eighth Street East.

In Sonoma County, 19,300 people were employed in manufacturing in December, or 10.5 percent of the total county work force. Of those, 10,900 workers were in the wine and food industries; the remaining 8,400 were in the durable goods sector, which includes computers and electronics.

Theirs is a sector under siege for years.

Piazza himself started to buy parts from China and have some manufacturing done there in 1999. Today, 75 percent of his metal castings come from there. "I didn't want to, but I had to stay in business," he told Thompson.

The U.S. manufacturing sector lost six million jobs between 2000 and 2009, although it has shown signs of fledgling recovery since, adding about 570,000 back as some companies shift operations overseas back to the United States.

Thompson has a very low rating from the National Association of Manufacturers: 27 percent for his career, based on his votes on what the association considers key issues.

But for Piazza, a registered Republican, the event was fruitful even though no great problems were resolved or, visibly at least, policy points won.

"Now I know whenever I have an issue he'll know who's bringing it," said Piazza, whose company sells pumps to the Navy and industries including the semiconductor and medical sectors. "He'll have a face to go with the problem."

"You do this stuff for the exposure, the access," said Piazza, who believes that American manufacturers are over-regulated, that the corporate tax system is unbalanced, and that the federal government should do more to level the playing field for U.S. companies that do business abroad.

Thompson spent nearly two hours at the factory, touring it, meeting employees and taking questions from them and businessmen from around the region.

"What can we do to get them to stay at home," said Robert Dathe, president of A-B Die Casting Co. in Hercules, saying that the Santa Rosa division of Agilent Technologies, to whom his company makes 30 percent of its sales, is increasingly sourcing from Malaysia, where it began to move plant operations in 1999. (That division, in a reorganization, has been spun off and renamed Keysight Technologies).

"We were told that in three years we wouldn't be supplying them unless we opened a division there," Dathe said.

Strengthening trade pacts, ensuring that environmental standards are required in overseas markets, overhauling the tax code, ensuring a well-educated workforce: all those things need to happen to "facilitate the things manufacturers need," Thompson said, before adding a cautionary note.

"Even if we do all that, there is no guarantee," he said.

Another factor, he suggested while standing on the factory floor, is a Congress riven with partisanship and pressured by special interests.

Describing an effort of the powerful Ways and Means Committee, on which he serves, to overhaul the tax system, Thompson said, "It started off with a bang."

Then, he said, after "ad nauseum" meetings, public hearings and constituent meetings, election season rolled around and "the train went off the proverbial track."

Similarly, he said that major changes to immigration laws, which Piazza also urged, appear promising one weekend and doomed the next.

But there remain retail politics. And Thompson, who was first elected in 1998 and has come to master them, said the people in the Price Pump conference room should call him.

"When issues come up it's a lot better to have a member of Congress speak up on your behalf," he said, "rather than to speak up on your own behalf without representation."

(You can reach Staff Writer Jeremy Hay at 521-5212 or jeremy.hay@pressdemocrat.com.)