“High quality” Electropolishing _ EP

“High quality” Electropolishing _ EP

EP is a method to polish metal surface that dissolves the surface of product by passing direct current in electrolytic solution. Therefore it is able to remove pollutions such as scales, sticking chips, abrasive grains which is not able to remove by only Super Micro Cleaning (SMC). Moreover the smooth surface is provided and reduces “real” surface area. And finally, EP treatment forms a uniform oxidized layer (passivation film) which prevents outgassing from inside of metals. Of course, cleaning after EP is SMC. We send products for you in the cleanest condition!



  1. 1.Smoothing and forming of oxidized layer
  2. 2.Improvement of vacuum property

Reduction of surface area by smoothing effect (Decrease of outgassing probability).

Low outgassing by forming of the oxidized layer.

Changes of the surface by EP process



Stainless steel Stainless steel 304 (L), 316 (L), 303, 310, SCS13, SCS14
Other materials molybdenum (Mo), tungsten (W), Inconel 600, HASTELLOY C-22

Application example

Stainless steel chamber

Tungsten (W) part

EP tubes

The quality of EP tube treated by SAN-AI PLANT is top-class in the world.

OD /in. OD /mm Length /mm
1/8” 3.18 2000
1/4” 6.35 4000
3/8” 9.53
1/2” 12.7
5/8” 15.88
3/4” 19.05
1” 25.4
6A 10.5
8A 13.8
10A 17.3
15A 21.7
20A 27.2
25A 34.0
32A 42.7
45A 48.6
50A 60.5

Aspect of EP tube and surface roughness curve

Final inspection is performed in clean room.
Professional examining staffs inspect all of EP tubes.

Aspect of Joints