Speed Rivets Improve Assembly of Turbochargers
Located in the small town of Strakonice, Czech Republic, is CZ a.s., one of the leading suppliers to the automotive industry in Eastern Europe. Its products include bearing and differential gearboxes, aluminum lids for water pumps and cylinder heads, and turbochargers for commercial diesel engines (1 to 16 litres, 25 to 400 kilowatts).
For 30 years, the company has been expanding its turbocharger production and product line. Currently, CZ makes five series of turbochargers, which are used in diesel engines for trucks, utility vehicles, buses and tractors. The five series are C12, C13, C14, K27 and K36, and they encompass 14 models.
CZ manufactures its turbochargers in a Nizhny Novgorod, Russia, plant co-owned with the Russian automaker GAZ. The plant follows just-in-time manufacturing practices and is ISO 9001 certified. Nearly 80 percent of production is exported to international markets.
Deere & Co., one of the world’s largest manufacturers of agricultural equipment, is CZ’s main customer for turbochargers. CZ is also a major supplier of turbofans to China’s truck manufacturers.
For many years, CZ assemblers attached an ID plate to the turbocharger’s compressor housing with hammer drive screws. Although the screws allowed for fast assembly, their heads were often damaged by the hammer. Equally important, the installed drive screws looked bad.
To correct both problems, CZ met with Bossard CZ s.r.o., located in nearby Modice, Czech Republic. Bossard recommended the company try UNIRIV speed rivets.
The tubular UNIRIV is designed for quick, blind-side installation in pocket or through holes. The rivet fastens a wide range of materials—including metals, plastics, composites, fiberglass and electronic components—and provides high shear strength.
Made of aluminum, steel or stainless steel, the rivet has a dome or countersunk head. Dome-head rivets come in nominal diameters of 1.9, 2.4, 3, 3.2, 4 and 4.8 millimeters, and have a gripping range from 1 to 11 millimeters. Countersunk-head rivets are available in diameters of 3, 3.2, 4 and 4.8 millimeters, and have a gripping range from 1 to 12 millimeters.
Rivets are installed with a one-way mandrel at a rate of up to 70 per minute. After the tool positions the rivet in the hole, the tool head is pulled back through the rivet so it expands and fills the hole. CZ assemblers like that the rivet is always secure in the tool prior to installation, even when the mandrel is subjected to vibrations. This eliminates the possibility of the rivet dropping into the hole or onto the floor.
For more information on speed rivets, call 319-277-5520 or visit