The MA-905 model from Shanghai Uni-star is made of zinc alloy. It has high gripping power and can be used on rock, concrete or brick.

Makers are devoting a larger portion of their expenditure to automated equipment. Facilities are also being upgraded.

Amid stiff competition and pricing pressure, anchor bolt suppliers in China are bolstering manufacturing capability to ensure product specifications meet international standards.

The majority of companies are investing substantially in high-tech, automated equipment. This includes high-precision lathes and centerless grinding, thread-rolling, tapping and drilling machines sourced from Germany, the US, Japan and large domestic suppliers.

Besides precise dimensions, these computer-controlled devices help yield models with acceptable tensile strength, tension and shear load levels, properties critical to performance and safety.

The use of 3-D designing software helps makers achieve accurate structure and measurement.

Although new machines are being acquired, suppliers are also improving existing technologies. Tai He Yu Precision Metals Co. Ltd has allotted about $2.5 million to the upgrading of current facilities, particularly those for lathing, punching, milling, drilling and cutting. This enables the supplier to offer a range of product options. Anchor bolts from Tai He Yu come in diameters of 0.5 to 40mm and lengths between 0.5 and 120mm.

Enhanced production at Shanghai Uni-star Industrial & Trading Co. Ltd is resulting in vibration-resistant designs with high gripping power, making them suitable for heavy-duty applications.

The company also emphasizes quality. Its 20-member QC team tests materials and components before volume production is initiated.

Dezhou Hualude Hardware Products Co. Ltd performs testing and inspection in accordance with the ISO 9001:2000 standard.

	This circular plate anchor bolt from Tai He Yu comes in stainless or carbon steel.

There are approximately 800 suppliers of anchor bolts in China, with factories located mainly in Shanghai and the provinces of Jiangsu and Zhejiang.

Most companies manufacture midrange and high-end designs, which target generally the construction industry. Highways and power transmission towers are among the major applications.

Products come in aluminum and carbon and stainless steel. Some makers also offer brass models, although the output of such has decreased dramatically in the past two years due to the compound's high cost.

Materials are both sourced domestically and imported. Tai He Yu, for instance, purchases metal from Japan and South Korea.

Zhejiang Yonghua Fasteners Co. Ltd, on the other hand, obtains copper, bronze, and carbon and stainless steel from local suppliers.

Prices depend mostly on the material used. For OEM models, the complexity of clients' design and technical requirements is another price determinant.

Sixty-five percent of exports carry in-house brands, with the rest under OEM and ODM contracts. Europe, Asia, the Middle East, the US and Australia are the overseas destinations.