Doing Business / CONCRETE BLOCK : Industry’s Foundation Built on Sand, Gravel and Cement

It takes more than sand and gravel to make it as a concrete block manufacturer. It takes cement, too. And since the late 1940s, manufacturers have relied on massive machines that crank out blocks the way Winchell’s does doughnuts.

Stanton-based Orco Block operates a dozen block-making machines that grind through 80 truckloads of raw material a day. The result is enough block each year to build a wall 6 feet tall and stretching from here to Portland, Ore.

The raw materials--washed sand, pea gravel, cement and water (and sometimes volcanic cinder to make a lighter-weight block)--are mixed together and poured into a block-making machine from giant hoppers. The machine shakes the mix, until it flows down and packs into molds.

The blocks that emerge are still wet and the consistency of stiff pudding. They are put into a 150-degree kiln for 16 hours to harden.

Finally, the blocks are stacked on pallets where they cure in the open air for one to four weeks before shipping.