STOP-OFF PAINT FOR:
GAS CARBURIZING & CARBONITRIDING
Properties
CONDURSAL 0090 is a very effective stop-off paint for all forms of gas carburizing and carbonitriding. Suited for both unalloyed and alloyed steels, it provides excellent protection against carbon pick-up for case depths up to 0.080". Unlike other protective coatings, it residues can be easily removed after heat treatment by washing in an agitated hot water or alkaline solution. That's the reason why CONDURSAL 0090 has become the stop-off compound which is most commonly used all over the world in continuously working heat treating lines for carburizing and carbonitriding. In order to meet the requirements of different applications, CONDURSAL 0090 is available in four modifications, differing in consistency but showing the same unique performance.
Condursal 0090, paste consistency
This consistency is best suited for use with a dispensing gun, which applies the paste from a pressurized container. (Similar to grease gun equipment) This method of application can be easily mechanized for mass production - as recently shown in fully computerized installations at FORD and GM plants. It provides sharply defined layers with maximum efficiency and is particularly suited for the protection of external threads, short gear teeth, splines, etc.
Condursal 0090 for spraying
In this case the rather liquid paint is applied using a pressurized container combined with spraying pistols, the nozzles of which normally have a diameter of .060 - .100". Spraying is most commonly used for continuous work, e.g., large series of pieces such as gears and axles.
Condursal 0090 for immersion
This grade is best suited for components with the area to be protected located at one end, so that coating by dipping is possible. Its consistency adheres quickly and does not tend to drip off. It is recommended that the excessive paste at the bottom of the work piece be removed by shaking or wiping so that it can be recovered. As long as the paste is not fully dry it may be reconditioned by simply adding small quantities of the "Special Thinner for Condursal 0090". When dipping the parts, it is useful to move the piece around to prevent air bubbles from sticking to the surface.
Condursal 0090 for painting
This "normal" consistency is most commonly used for manual application, whenever the variety of work pieces or areas to be coated do not allow automatic or mechanized coating. Application of this paint is similar to oil based paint using a flat soft bristle brush.
Our most widely used stop-off paint, it can be used for all forms of both gas carburizing and carbonitriding. CONDURSAL 0090 provides excellent protection against carbon pick up for case depths up to 0.80". Unlike other protective coatings, CONDURSAL 0090 can be removed after the heat treating process simply by washing the part in an agitated hot water or alkaline solution. Due to its ease of removal, CONDURSAL 0090 has become the insulation stop-off which is most commonly used all over the world.
| Pricing (per can) | 1-5 cans | 6+ | case lot |
| CN-1K9 (quart) | Call | Call | Call |
| CN-4K9 (gallon) | Call | Call | Call |
| Duffy Special Thinners | 1-5 cans | 6+ | case lot |
| CN-QT White Label | Call | Call | Call |
| CN-GAL White Label | Call | Call | Call |
CONDURSAL 0090 Instructions For Use:
Before applying, stir the contents of the CONDURSAL 0090 tin thoroughly, which is of importance especially after long storage time. As received, CONDURSAL 0090 is ready for use, i.e. suited for the mode of application noted on the label of the tin.
The work pieces to be protected must be free of oil, grease and rust prior to coating. This can be accomplished by vapor degreasing, washing with alkaline solution or blasting.
Temperature of surfaces to be coated should not exceed 90° F, which should be kept in mind particularly if the parts have been vapor degreased.
Apply a continuous and non-streaky layer of Condursal 0090 to the area to be protected by either painting, dipping, spraying, or using "grease gun equipment" as mentioned above. Thickness of the coating after drying should always be approximately .008 - .012".
Normally, i.e. for case depths up to 0.080, only one coating is necessary for optimum protection.
During use, with the tin open, Condursal 0090 will slightly thicken in the course of time due to evaporation of the solvent. If required to maintain proper application, add small quantities of "Special Thinner for Condursal 0090" in order to restore the original consistency. Avoid over thinning and do not use chlorinated solvents for thinning. Chlorinated solvents would lead to severe corrosion problems.
After proper application, the coating should be allowed to air dry for 1 - 3 hours before the work pieces are placed in the heat-treating furnace.
Do no combine, in the same batch, parts coated with Condursal 0090 with others coated with water or silicate based stop-off paints. Water and silicate based stop-off paints set free water vapor during heat-up, which would effect the Condursal 0090 layer.
When loading the coated parts into fixtures or baskets, take care that the coated areas do not come into contact with other pieces or the baskets in order to avoid damage to the protective layer or unwanted insulation of non-coated neighboring parts.
Special Notes:
Avoid excessive storage time, particularly at elevated atmospheric humidity or any other possible contact of water or water vapor with the Condursal 0090 layer after drying.
Do not preheat coated parts at temperatures exceeding 350° F with oxygen present. Both contact with water and oxidizing of the paint may cause run-off problems during the carburizing process to follow.
After carburizing, work pieces protected with Condursal 0090 can be quenched directly. Residues of Condursal 0090 do not dissolve in quenching oil or in quenching salt.
Removal of Residues:
Once the heat treating process is finished the residues of Condursal 0090 can be removed completely by simply washing with hot water or alkaline solution in either spray or immersion type washers.
If after washing there should be any residues left, for instance in holes or internal threads, they can be easily removed by rubbing or brushing because of their powdery appearance.
Parts quenched in nitrate salt bath must be cleaned carefully, otherwise corrosion might occur due to damp salt residues on the previously coated areas.
Cleaning of brushes and other equipment:
To clean brushes and other equipment used for applying Condursal 0090, the "Special Thinner for Condursal 0090", or similar solvents may be used. Water or alkaline are not suited for this purpose.
Storage:
Condursal 0090 should be stored in a dry cool place.
Trouble Shooting Preface:
Condursal 0090 is as easily applied as an oil based paint. As with all painting, it is important to clean and degrease the surfaces to be coated thoroughly. A soft bristle brush should be used to insure a uniform coating thickness. Allow the coating to dry thoroughly before the work piece is put into the furnace. The following list is provided to address possible causes on ineffective stop-off of this paint.
CONDURSAL 0090 Trouble Shooting:
Trouble
Paint runs off after applying by painting, spraying or immersion.
Possible Reasons:
1. Paint was stored at too high a temperature.
2. work pieces have not been degreased satisfactorily prior to coating.
3. work pieces were too warm at the time when paint was applied. For instance after vapor degreasing.
4. Paint has been thinned excessively.
5. Paint has been applied in too thick a coating.
How to Avoid:
Store at ambient temperature.
Clean parts thoroughly by vapor degreasing or alkaline washing.
Let work pieces cool down to ambient temperature (68 to 80 degrees F.) prior to coating.
Use paint as delivered; add small amounts of "Special Thinner" only if thickening has occurred due to evaporation of solvent.
Apply paint in a thin coating of uniform thickness (.008-.012"); if necessary because of deep case, apply twice.
Trouble
Paint pops off after drying.
Possible Reasons:
1. Surfaces of work pieces were wet or greasy when paint was applied.
2. Coated parts have been stored for too long a period of time at high atmospheric humidity.
How to Avoid:
Clean parts thoroughly by vapor degreasing or alkaline washing and make sure that they are dry prior to coating.
Store coated parts at a dry place and for not more than 24 hours prior to carburizing.
Trouble
Paint runs off in the carburizing furnace.
Possible Reasons:
1. Paint has been applied in too thick a layer/ coating has not been allowed to dry thoroughly.
2. Coated parts have been stored for too long a period at high atmospheric humidity.
3. Parts have been preheated at temperatures of more than 400 degrees F. with oxygen present.
4. Coating has come into contact with humidity in the carburizing furnace due to:
- defective endothermic generator.
- leaking of retort cooling system.
- incomplete cracking of liquid carburizing media
- putting coated parts in the furnace together with other work pieces insulated with water or silicate based stop-off paint.
5. Coating has come into contact with oxygen in the carburizing furnace due to:
- incorrect atmosphere regulation.
- cracking/ leaking of the retort of the furnace.
How to Avoid:
Apply paint in a thin coating of uniform thickness (.008-.012") and let dry thoroughly.
Avoid storage of the coated parts at high atmospheric humidity.
Limit preheating temperatures to 350 degrees F. Max.
Repair generator.
Repair cooling system.
Start feed of liquid carburizing media after the furnace has reached 1400 degrees F. minimum.
Do not combine in the same batch parts coated with Condursal 0090 with others coated with water or silicate based stop-off paints.
Make sure by purging with nitrogen that furnace atmosphere, even in the beginning of the carburizing process, does not contain oxygen.
Repair retort.
Trouble
Residues of the paint are hard to remove after carburizing/ surface attack is noted.
Possible Reasons:
1. Coating has come into contact with humidity.
2. Coated parts have been cooled down after carburizing and then reheated for quenching.
How to Avoid:
SEE RUN-OFF PROBLEMS
Remove residues of the parts after carburizing.
Trouble
Protection against carbon pickup has been found to be non-uniform or non-satisfactory.
Possible Reasons:
Paint has been applied in a too thin or non-uniform layer.
How to Avoid:
Stir paint thoroughly prior to use; apply paint in a layer of even thickness; if necessary for deep cases apply twice but keep in mind that first coating must be dry prior to application of second one.
