abstract |
A lubricating coating which can prevent the occurrence of galling even when makeup is carried out with a high torque and which has excellent rust preventing properties is formed on the contact surfaces of a pin and/or a box of a tubular threaded joint. The lubricating coating contains copolymer particles made from particles of an acrylic-silicone copolymer with an average particle diameter of 10 - 50 μm dispersed in a highly viscous matrix made from a mixture of a rosin-based substance selected from rosin and its derivatives, wax, a metal soap, and a basic metal salt of an aromatic organic acid (such as highly basic Ca sulfonate). |