Send Message
news

Surface treatment AP/MP/BA/EP

October 28, 2023

AP: pickling pipe (anneal treatment & passivation) / (acid pickling).


MP: mechanical grinding process or mechanical polish (mechanical polish).


BA: bright passivation treatment or bright annealing (bright anneal treatment)/(bright annealing).


EP: electrolytic grinding treatment.

 

Stainless steel BA tube - bright annealed tube (vacuum bright annealed tube)
It is the abbreviation of atmosphere protection heat treatment (bright annealed), also known as: stainless steel BA pipe, clean pipe, bright annealed pipe, seamless pipe, gas line tube, high purity gas line, tube.


Material: 304, 316L.


Standards: ASTM A249, A269, A270, 3A and BPE standard, JIS G3447. G3459.


Forming: mainly multi-roller cold rolling, the size can reach 0.2%, and the inner surface finish Ra<0.45 um.


Features: accurate dimensions, smooth surface, overall cleanliness, inner surface unpolished is better than polished finish.


Raw materials: meet ASTM A269 standards, double furnace steel ingots can be used for special requirements.


Manufacturing: cold rolling + fine drawing, dimensional accuracy reaches about 0.05mm, inner surface Ra is about 0.4 microns.


Heat treatment: bright solid solution (annealing) under the protection of reducing atmosphere.


Cleaning: use SC2286 cleaning agent for ultrasonic Ultrasonic cleaning. That is to say, it must be degreased and degreased.


Inspection: eddy current non-detection + water pressure, etc.


Finishing: straightening + sizing + polishing.


Packaging: Inkjet coding + PE bag + cap + shock-absorbing packaging + Gechen packaging + protection.


Purpose: Special gas or liquid transportation, and also the base material of EP pipes.


Applicable industries: biopharmaceuticals, electronic clean workshops, high-purity gases, high-demand clean laboratories, liquid crystal displays, solar photovoltaics, polysilicon and other fields. Semiconductor industry, liquid crystal industry, pharmaceutical industry, instrumentation system, compressed air, ultra-high purity gas, chemical system, WFI system and other gas pipeline systems or clean rooms or equipment with high-purity and ultra-high-purity requirements.

 

EP process: based on high-quality BA pipes, the inner surface is electrochemically polished, then purified with high-purity water, and packed with nitrogen.


Diameter control: tolerance ±0.02mm (0.1%).


Length control: tolerance ±0.05mm.


Straightness: no more than 0.1mm/m.


Surface roughness: EP tube Ra≤0.15μm.


Concentricity control: tolerance ±0.01mm.


Mechanical property control: Hardness HRB (75~580), strength δb and elongation Ψ can be adjusted and controlled.


Heat treatment: solid solution treatment in reducing atmosphere.


Packaging: double bagged and capped.

 

EP: bright annealing--->non-destructive testing--->chemical polishing---->electropolishing.


BA: bright annealing--->non-destructive testing--->one cleaning.


CP/AP: heat treatment--->non-destructive testing--->chemical polishing.