Career in EPC Cost Estimation

A: A lot of people assume CA is a corrosion study issue, not a weight issue. Drop it and tonnage collapses quietly. Supports hurt total installed cost, but they don't live in pipe weight MTOs. Flanges are already in the bill if the iso shows them; shop fabrication doesn't erase mass. RT drives labor and schedule, not steel weight, so it can't explain a 20% delta.

A: Congestion kills arc time. Scaffolding moves, permits, and stop‑start welding compound each other. Skill level matters, but even top welders can't outrun access limits. AUT adds delay, yet it's usually planned and doesn't halve productivity alone. A bad WPS shows up as repairs and rejects, not a uniform drop across all spools.

A: The factor multiplies, it doesn't add. Mixing it with contingency muddies two different buckets. Offshore factors look familiar and tempting, but they overshoot for onshore steel and civils. Spares and commissioning are real costs, yet they sit outside the installation factor and belong in indirects.

A: This is classic sour but not extreme. NACE controls and PWHT address SSC without dragging in CRA pricing. Plain carbon steel ignores the partial pressure trigger and won't survive audit. Full 316L overshoots chloride and temperature reality. Full cladding solves everything technically, but the cost signal is wrong at this design maturity.

A: Detail and uncertainty need to line up. Using mature unit rates suggests tighter definition, but the contingency screams concept-level risk. Fixed percentages don't exist across classes. Unit rates never carry project risk; they carry productivity assumptions. Splitting contingency to indirects alone ignores design growth in the direct scope.

A: CUI isn't about heat balance, it's about access. Every strip and reinstall cycle drags scaffolding and labor. Insulation rates move with markets but not that sharply. Wall thickness affects steel tonnage, not insulation scope. Heat loss calcs rarely change once the process is set.

A: Straight multiplication answers the question asked. The kg/man‑hour approach swaps fabrication logic into erection work. Brownfield factors belong in contingency or separate productivity cases, not hidden math. Supervision is an indirect and shouldn't pollute direct labor benchmarks.

A: Pressure drives steel. API 650 tanks live near zero gauge, so shell thickness drops fast. Hydrotesting still happens, just differently. Inspection doesn't vanish; it's just tailored. Material grades overlap heavily, so alloy swaps aren't the lever here.

A: P80 sits three‑quarters of the way from P50 to P90. That delta is USD 23 MM; 75% of it is roughly USD 17 MM. Normalize that to P50 and you land near 17%. The smaller numbers ignore the probabilistic spread. The larger one jumps straight to P90, which management didn't ask for.