NOTE 1 : Recommended cleaning solvents : (TB 11-003), (TB 11-011) or (TB 11-912). Post-change 20242
NOTE 2 : Sealant (TB 09-013A) is replaced with sealant (TB 09-918) as it is incompatible with protection of the new spar.
Sealants Table 201
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Validity : S / N 1 - 9999 20 00-09Page 201
(BA) SEP 04
3. SEALING TERMINOLOGY
A. Fay sealing
Fay seal is to apply sealant to one of the faying surfaces of a joint, immediately before final closure of the joint, in such a thickness that a small continuous bead of sealant is squeezed out from all open sides of the periphery of the mating surfaces when they are fastened together.
B. Pre-pack sealing
Pre-pack seal is to fill gaps or cavities with an excess of sealant, immediately prior to assembly, so that a small continuous bead of sealant is squeezed out from all open sides of the periphery of the mating surfaces when they are fastened together.
C. Injection sealing
Injection seal is to force sealant from a pressure gun into gaps or cavities between two or more assembled parts until the sealant extrudes from all other openings and the void is filled.
D. Fillet sealing
Fillet seal is to apply a bead of sealant to a seam or joint after the assembly has been fastened.
E. Brush coating
Brush coat is to apply an overcoating or continuous film of sealant by use of a brush.
4. REQUIREMENTS
To achieve maximum integrity, the various seals should be completed by a brush coat over all attachments. Sealants shall be identified and stored in designated area.
Sealants shall not be more than 6 months old when used.
Unmixed compounds shall not be stored at temperatures exceeding 25°C (77°F).
Sealants which have been pre-mixed, degassed and frozen shall be stored at -40°C (-40°F) or lower. It is recommended to use quick freeze technique to immediately slow down the compound changes. The maximum shelf life beyond the date of mixing is seven days provided that all storage is at a temperature of -40°C (-40°F) or lower.
Frozen sealant may be thawed by any suitable means which does not cause contamination or overheating of the sealant and does not shorten the application time of the sealant to an impractical period. Examples : thawing by exposure to ambient air temperature ; accelerated thawing by exposure in a constant temperature bath (using clean, hot water) ; accelerated thawing in a microwave oven. In any case, thawing temperature and time shall be adjusted to give a thawed sealant temperature between 16 and 27°C (61 and 81°F) at the moment of the sealant application.
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