if can buy thread gages from China, and then used in USA company directly? The standard is equivalent？

the American Society of Mechanical Engineers (ASME) develops standards for compressors, cranes and hoists, drawings and terminology, elevators and escalators, fasteners, flow measurement, industrial trucks, manlifts, nuclear, environmental control, piping, pressure vessels, pumps, storage tanks, turbines and much more.

GB is an abbreviation of Guojia Biaozhun, meaning "national standard". GB standards are the Chinese national standards issued by the Standardization Administration of China (SAC), the Chinese National Committee of the ISO and the IEC.

Why do I need to comply with GB Standards ?

In China, All products or services must be complied with GB standards, no matter domestic or imported products, Any products being sold in China are required to be tested in order to ensure their compliance with GB standards;
If you want to export products or services to huge Chinese market, need to understand and be aware of the complexities and necessary requirements under the vast range of GB standards, need to ensure they are meet the requirements of GB china national standards; 　
The outcome of failing to comply with GB standards can include the rejection of products during importation as well as products being seized from stores, resulting in a significant impact on retailers and manufacturers in terms of

so when you order thread gauges , you should tell us the standard of thread gages.  for example:ASME B1.5 /ANSI 1.2...... ISO 228-2