Tools, Equipment, and Shop Fabrication
What this domain tests
This domain tests safe and correct use of cutting, forming, and fastening tools, plus shop fabrication of fittings that fit the job.
Core rules
- Use a sharp insulation knife for fiberglass and mineral wool; a serrated blade helps cut blanket without tearing the facing. Cellular glass and calcium silicate are cut with saws or special tools and generate dust, so use dust control and eye protection.
- Facing and jacketing are cut with aviation snips or shears; metal edges must be deburred.
- Fasten with the specified staples, bands, wire, or adhesive. Staples should not crush the insulation or tear the vapor retarder.
- Shop fabrication follows the job dimensions, not nominal pipe size alone. Measure outside diameter and check the fitting angle.
- Lay out an elbow cover by dividing the arc into gores; the number of gores depends on the radius and material. Dry-fit before sealing.
- Keep guards in place on powered tools; secure material before cutting; and store fabricated pieces so they stay clean and dry.
Worked example
To fabricate a 90° elbow cover from mineral wool blanket, measure the elbow outside diameter and centerline radius, divide the arc into equal segments, for example eight gores, cut the wedges so the pieces close without gaps, and dry-fit. Then fasten and seal the jacket. The reasoning: gaps at gores are common leak points, especially on cold lines.
Traps
Using a dull knife and tearing the jacket; cutting by nominal pipe size; making too few gores; stapling through a vapor retarder without sealing; and cutting metal jacketing without gloves or eye protection.