THREADED CONNECTION FOR OIL COUNTRY TUBULAR GOODS AND METHOD FOR PRODUCING THREADED CONNECTION FOR OIL COUNTRY TUBULAR GOODS

摘要

This invention provides a threaded connection for oil country tubular goodsthat exhibits excellent corrosion resistance and galling resistance, and amethod forproducing the threaded connection for oil country tubular goods. Inparticular, themethod for producing the threaded connection for oil country tubular goods isamethod for producing a threaded connection for oil country tubular goods thatincludes a pin (3) and a box (4). The method includes a Zn-Ni alloy platinglayerformation step of forming a Zn-Ni alloy plating layer (100), and a chromatecoatingformation step of forming a chromate coating (200) after the Zn-Ni alloyplatinglayer formation step. The chromate coating formation step includes a chromatetreatment step and a drying step. The chromate coating formation step satisfyoneor more conditions selected from the following conditions 1 to 3.Condition 1: stirring speed of the chromating solution in the chromatetreatment step: a linear speed of 0.5 m/s or more;Condition 2: chromate treatment time in the chromate treatment step: less than50 seconds; andCondition 3: drying temperature in the drying step: 60°C or less.