Help with curved lines and shading

[Psaumure]

Is there anyone that can help with curved line shading? I'm trying to duplicate this sphere on the right with the lines that are going around the sphere. I am having problems getting the shading to follow the line around the bends. Currently I have three different color lines that I have blended. Using the blended lines does not give me a uniform thickness throughout the bends. Is there a technique to bend a line and hold the gradient shading? Any suggestions or help would be greatly appreciated.