Surface Treatment: Nickel Plating Tubes

http://www.proplate.com/nickel1.htm

are you plating to acheive a low R_a, or do you desire some other properties of the N_i ?

for surface finish there might be other options.

Have you looked at electroless nickel plating? http://www.corrosion-doctors.org/MetalCoatings/Electroless.htm This process is better at plating inside details than electroplating.

Why plate, instead of using a solid nickel tube? What is the application?

If it is a high nickel austenitic stainless steel tube I would higly recommend that you take a look at the Kolsterising tretament process.

www.kolsterising.info

Kolsterising can deliver a surface hardness of 68 HRc without dimensional change to the component and without negitively the corrosion resistance of certain austenitic stainless steels.

if it is just a surface finish issue you may be able to slurry finish it 2-5 R_a

If the length is long compared to the diameter, and you are electroplating, you may need to place a current source inside the tube. The electric field inside a closed surface is zero if there are no sources inside, and a long tube in electroplate solution acts like a closed surface.