1. All materials should be handled with gloves cleaning.
2. All materials should be stored in clean, sealed, polyethylene bags.
October 21, 1976
To: Distribution
From: Gary Fitzpatrick & Ned Britt
Subject: CHEMICAL CLEANING PROCEDURES
http://www.1blink.com/search.cgi?q=Chemical%2BCleaning%2BProcedures&submit=blink%21
We've attached a copy of our suggested cleaning procedure specification.
Specification: Chemical Cleaning
1.0 SCOPE
This specification describes the procedures established for cleaning most of the materials used in converters and vacuum systems. Included are:
a. Tantalum, tungsten, niobium, and vanadium
b. Molybdenum
c. Titanium
d. Nickel
e. Copper
f. Glass
g. Inconel
h. 300 series stainless steel
i. 400 series stainless steel
2.0 EQUIPMENT
1. Ultrasonic Cleaner
2. Vapor Degreaser
3. Fume Hood
4. Hot Plate
5. Stainless Steel Beakers
6. Polyethylene Beakers
3.0 MATERIALS
1. Acetone - reagent grade or better
2. Igepal
3. Ethyl Alcohol - reagent grade or better
4. Dry hot air (from blower)
5. Iron powder
6. DI-H2O - 1 megaohm-cm or better
7. Tap water
8. HNO3 - reagent or better
9. H2SO4 - reagent or better
10. HCl - reagent or better
11. HF - reagent or better
12. Nitrogen - laboratory grade or better
13. Trichlorethylene
4.0 CLEANING TECHNIQUES
4.1 Ultrasonic Cleaning
Submerse component into a clean beaker with the required solvent. Place the beaker in the ultrasonic tank with the tank water 1/2" to 2-1/2" deep. Set the ultrasonic generator for maximum agitation. Ultrasonic clean for 2 minutes or until clean.
4.2 Ultrasonic Rinse
Follow procedure 4.1 except clean for 30 seconds.
4.3 Vapor Degreasing
To Be Specified.
4.4 Acid Etching
Insulators and brazes between ceramic and metal flange must not be exposed to acids.
For cleaning pour sufficient amount of acid solution into a SS or polyethlene beakers (as specified below) to cover the part. Dip piece to be etched into the solution for approximately 15 seconds. Repeat etch if necessary.
The etching compositions can be mixed and stored providing they are properly contained. Solutions containing HF must be stored in polyethyene bottles. Fresh solutions should be prepared at least weekly. Used etch should be disposed of - not returned to storage.
5.0 CLEANING PROCEDURES
All internal converter surfaces or surfaces which will be exposed to cesium.
5.1 Step I - Organic Solvent Cleaning
1. Ultrasonically clean in trichlorethyene if only minor organic contamination is present
or
2. Ultrasonically clean in acetone.
5.2 Step II - Acid Etching - Etching Solutions
1. Tantalum, tungsten, niobium and vanadium - use poly beaker
2 parts DI-H2O
10 parts HNO3
5 parts HF
2. Molybdenum - use poly beaker
95 parts H2SO4
4.5 parts HNO3
0.5 parts HF
3. Titanium - use poly beaker
50 parts DI-H2O
50 parts HNO3
2 parts HF (critical)
4. Nickel
6 parts DI-H2O
3 parts HNO3
1 parts HCl
5. Copper
60 parts DI-H2O (Mix materials slowly in order shown)
1 parts HCl
100 parts HNO3
160 parts H2SO4
6. Glass - use poly beaker
60 parts DI-H2O
33 parts HNO3
5 parts HF
2 parts Igedal
7. Inconel - use S.S. beaker
16 parts DI-H2O
5 parts HNO3
1 parts HF
Add 0.8 gm iron power per 100 ml of solution. Heat solution to between 100 and 125 F (52 C) (not higher).
8. 300 series stainless steel - use SS beaker
84 parts DI-H2O
15 parts HNO3
2 parts HF
Heat solution to 125 F (52 C)
9. 400 series stainless steel - use SS beaker
First etch in a solution of
75 parts DI-H2O
25 parts H2SO4
Follow with an etch in a solution of
75 parts DI-H2O
25 parts HNO3
5.3 Step III - Rinse in DI Water
Quench component in DI-H20 and transfer to a container receiving a flow of DI-H2O. Component should remain DI-H2O, for approximately 60 seconds.
5.4 Step IV - Ultrasonic Acetone Rinse
Transfer component from DI-H2O to a clean beaker containing acetone.
5.5 Step V - Ultrasonic Ethyl Alcohol Rinse
Transfer component from acetone to a clean beaker containing ethyl alcohol.
5.6 Step VI - Blow Dry
Remove component from ethyl alcohol after 15 seconds and blow dry with laboratory grade nitrogen.
6.0 CLEANING PROCEDURES
All parts to be used in vacuum systems not subject to section 5 above.
6.1 Step I - Organic Solvent Cleaning
Ultrasonically clean in trichlorethylene if only minor organic contamination is present.
or
Vapor degrease in trichlorethl or ethylene if large amounts of hydrocarbons are present.
6.2 Step II - Ultrasonic Acetone Rinse
Transfer component from DI-H20 to a clean beaker containing reagent grade acetone.
6.3 Step III - Ultrasonic Ethyl Alcohol Rinse
Transfer component from acetone to a clean beaker containing ethyl alcohol.
6.4 Step III - Blow Dry
Remove component from ethyl alcohol after 15 seconds and blow dry with laboratory grade nitrogen.
7.0 STORAGE AND HANDLING
1. All materials should be handled with gloves cleaning.
2. All materials should be stored in clean, sealed, polyethylene bags.