threaded connection for tubular petroleum products and method for producing threaded connection for tubular petroleum products

摘要

the present invention provides a threaded connection for tubular oil products that exhibits excellent corrosion resistance and resistance to adhesive wear and a method for producing the threaded connection for tubular oil products. in particular, the method for producing the threaded connection for tubular petroleum products is a method for producing the threaded connection for tubular petroleum products that includes a pin (3) and a box (4). the method includes a step of forming the zn-ni alloy coating layer to form a zn-ni alloy coating layer (100) and a chromate coating forming step to form a chromate coating (200) after the zn-ni alloy coating layer formation step. the chromate coating formation step includes a chromate treatment step and a drying step. the chromate coating formation step satisfies one or more conditions selected from the following conditions 1 to 3. condition 1: stirring speed of the chromate solution in the chromate treatment step: a linear speed of 0.5 m / s or more ; condition 2: chromate treatment time in the chromate treatment step: less than 50 seconds; and condition 3: drying temperature in the drying step: 60ºc or less.