Support, considered.

Research record

The detail behind
the study.

Source-linked work for this revision. Reported checks describe the stated model or test; physical qualification and applicability to the current retrofit remain separate.

Original Subfield body-handling saddles, modeled against the permanent tank frame.

32 new solids. 173 CAD tests passed. No selected rigging, lifting rating or manufacturing release.

Tank / original underside saddles

Saddle / separate bearing and bond parts

Frame / actual CAD section

Handling / clearance references only

CONCEPT / UNRATED development package for SC-013. Two original continuous underside saddles align with permanent base crossmembers 2 and 5 at X -775.5 and +775.5 mm. Each has one saddle with integral guides, three lower bearing pads, two lower side pads and ten nominal bond volumes. Thirty-two original solids are added to the unchanged 2,633-body source tank, producing a separate 2,665-body candidate.

All 173 CAD tests, 34 unit checks and 31 whole-tank fit/export checks passed. Added solids clear the actual tank; nominal body bonds touch its skin; all six lower pad footprints align with existing internal shoes. Eight existing side-level extraction corridors remain clear. STEP transport checks preserve every original supplier body. These checks establish geometry only, not load capacity.

The orange reference volumes reserve space for an engineered spread arrangement. They are NOT slings, protectors, hooks or a spreader and are excluded from the product STEP. Separate reference STEP files carry a reference suffix. Four inward-directed reference legs intersect the tank; the rejected case is recorded in tank-fit/fit-record.json. No WLL, proof-load instruction or lifting authorization is provided. Whole-body handling and roof-only handling remain distinct; no roof-only points are introduced.

The model uses 12 mm saddle thickness, 7.5 mm bearing pads and two 0.5 mm bond layers at each interface. Guide channel width is 120 mm; guides project 24.5 mm beneath the original floor. These are preliminary allocations, not qualified material, sling or tolerance specifications. Assumed added mass for both saddles is 20.201 kg, based on 1,560 kg/m3 composite and 1,200 kg/m3 bond density. The existing 500 lb tank mass goal remains unmet.

The full coupled load path through saddle, pads, bonds, skin, inner shoes, permanent base members and joints requires strength/stiffness, local bearing, slip, creep, impact/damage and durability assessment. Complete mass, center of gravity, retained contents, tilt, load sharing and dynamic loads remain unresolved. Select and qualify actual rigging and edge protection together. Bedding support, ground clearance and sling removal also remain open. Laminate, adhesive, fiber orientation, tooling/draft, process, preparation/cure, inspection and production tolerances are not released.

The 150-scope ledger records 51 partially modeled concepts, 63 not modeled, 31 deferred and 5 non-geometric. No scope becomes ready for release from these images or geometry checks. Complete manufacturing design remains in progress.