![]() | COMMERCIAL ENGINE STANDARD PRACTICES MANUAL | Dated: 02/09/2017 |
SPM 70-43-19 APPLICATION OF SOLID-FILM LUBRICANT - C02-027 | ||
TASK 70-43-19-640-005 |
1 . | General. |
CAUTION: |
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A. | This solid-film coating is a dry molybdenum disulfide lubricant dispersed in a high-temperature synthetic resin binder C02-027. The coating forms a heat-resistant lubricating surface on mating parts to prevent galling or seizing. The material is applied by brushing or spraying. |
2 . | Equipment and Material. |
Subtask 70-43-19-640-054 |
A. | For spray applications, following manufacturer's recommendation, use an external atomizing-type spray gun. |
B. | Materials: |
3 . | Procedure. |
Subtask 70-43-19-640-051 |
A. | Prepare the surface and apply the solid-film lubricant as follows: |
WARNING: |
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CAUTION: |
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(1) | Clean the surface to be coated by wiping with clean cheesecloth moistened with general solvent C04-001 or C04-003. Repeat, if necessary, until the surface of the cloth remains clean. Let the cleaned surface air-dry, or wipe it dry with clean, dry cheesecloth. |
Subtask 70-43-19-640-055 |
(2) | Apply the coating with one of the two methods: |
(a) | Spray application: |
1 | Open the container of solid-film lubricant C02-027 and stir contents until thoroughly mixed. Pour out a quantity sufficient for about one hour of use into a clean container. Reseal the original container. |
CAUTION: |
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2 | Mix these ingredients (by weight): |
Solid Film Lubricant C02-027: 36.4% ± 1.3% |
Methyl-Ethyl-Ketone (ASTM D 740) C04-001: 31.8% ± 1.3% |
Industrial Toluene C04-036: 31.8% ± 1.3% |
Mixing instructions: Mix the lubricant in a pail for a minimum of 15 minutes. Check the bottom of the pail for settling. Add the lubricant to a clean mixing vessel. While mixing, add the Methyl-Ethyl-Ketone C04-001. Continue to mix for 5-10 minutes. While mixing, add the toluene C04-036. Continue to mix for 15-20 minutes. |
3 | Apply the solid-film lubricant to the cleaned surfaces by spraying with an external, atomizing-type spray gun (refer to Step 2.(A) in Subtask 70-43-19-640-054). The coating must be uniform, thin, and free from lumps, streaks, and foreign material. Stir the lubricant as often as possible, using a wide paddle. Optimum condition is obtained by continuous stirring. |
NOTE: |
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(b) | Brush application: |
1 | Open the container of solid-film lubricant C02-027 and stir contents until thoroughly mixed. Pour out a quantity sufficient for about one hour's use into a clean container. Reseal the original container. |
NOTE: |
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CAUTION: |
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2 | Apply the solid-film lubricant to the cleaned surfaces with a camel's hair brush. The coating must be uniform, thin, and free from lumps, streaks, and foreign material. Stir the lubricant as often as possible, using a wide paddle. Optimum condition is obtained by continuous stirring. |
NOTE: |
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Subtask 70-43-19-640-056 |
(3) | Let coated surfaces air-dry for 15 minutes minimum until wet appearance disappears, or until coating is dull in appearance. Heat below 175°F (79°C) maximum may be used to accelerate drying. |
(4) | Check thickness and continuity of coating. No metal must be visible through the coating. If necessary, to complete coverage or to increase thickness, re-coat and air-dry as described in Step 3.A.(3) in Subtask 70-43-19-640-056, avoiding overlapping previously coated areas. Refer to Step 4.A.(5) in Subtask 70-43-19-640-052. |
(5) | Bake the air-dried coated parts in a preheated oven at 375 to 425°F (191 to 218°C) for 60 to 90 minutes (part temperature). |
NOTE: |
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CAUTION: |
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(6) | Let the parts air-cool. |
4 . | Quality Provisions. |
Subtask 70-43-19-640-052 |
A. | Material must be used before its shelf-life period is exceeded. The coating, after it is oven cured, must have the following characteristics: |
(1) | The cured coating must appear uniform in color and must be smooth, free from any cracks, scratches, pinholes, blisters, bubbles, runs, sags, or other surface imperfections. |
(2) | The coating homogeneity must be determined by visual appearance of the coating after thermal curing. Properly mixed coating, after it is cured, must appear dark grey to black with a dull finish. A green cast or glossy appearance of the cured coating is not acceptable. Over cured parts (excessive time or temperature) may exhibit a brown cast with yellow spots of molybdenum oxide and must be removed and re-coated. Any other coloration or surface texture than that specified must not be acceptable. |
(3) | The coating must exhibit complete coverage in the areas specified in related repair instructions. Coating on areas other than those specified, must not be permitted. It is permitted to apply and re-cure additional coating to areas with inadequate coverage, up to a maximum of two additional times, after curing the initial coating application. The adhesion test requirements in Step 4.A.(5) Subtask 70-43-19-640-052 must be met after the final curing of the coating has been completed. |
WARNING: |
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(4) | The cured coating on the part or test sample must be wiped for one minute with a clean white cloth or cotton swab saturated with general solvent C04-001 or C04-003. Coating dissolution during wiping or removal that exposes the underlying material is not permitted. Unacceptable coatings must be removed and re-coated. |
(5) | After parts have been tested previously to meet cure test requirement, adhesion of the cured coating must be determined by placing a strip of paint adhesion testing tape C10-189 or transparent film tape C10-251 firmly on either the cured coated part or an adhesion sample, and removing it with a quick continuous motion. Adhesion and cure test samples in Step 4.A.(4) Subtask 70-43-19-640-052 must be of a material having a similar composition, surface preparation, and thermal spray coatings as the part being coated. The coating must be continuously bonded to the surface and must not exhibit any spallation or lifting. A light deposit of powdery material clinging to the tape must not be cause for rejection. |
5 . | Handling. |
Subtask 70-43-19-640-053 |
A. | Coated parts shall be handled in such a way that no chipping, scratching or other damage can occur. |