IBC Stacking System¶
1. Purpose¶
TBS-001's three-circuit water system requires four 1,000 L caged composite totes arranged in a 2×2 stack in the right end zone of the container. Two Blue supply totes (IBC-1 and IBC-2) sit on top; one Brown recycle tote (IBC-3) and one Waste tote (IBC-4) sit on the bottom. A welded mild steel restraint-only frame restrains all four direct-stacked totes for transport, and maintains a 270mm plumbing corridor between the near and far columns for internal pipe routing, valves, and the equipment panel.
Design goals:
- Restrain 4× 1,000 L caged totes in a 2×2 direct-stack (2 columns × 2 tiers)
- Restrain all totes for road transport with D-ring lashing points
- Maintain a central plumbing corridor for pipe routing and valve access
- Enable external fill and drain without opening cargo doors
- Fit within the 2,388mm container ceiling height with adequate clearance
Interactive 3D model — the four IBC totes, the welded stacking frame, and the plumbing corridor. Drag to orbit, scroll to zoom.
2. IBC Totes¶
2.1 Specification¶
| Parameter | Value |
|---|---|
| Model | Schütz Ecobulk MX 1000L (or equivalent US 48×40 caged composite tote) |
| Capacity | 1,000 L (~264 US gal) per tote. "600 L" / "1,000 L" are fill levels, not tote sizes — all four totes are identical |
| Overall dimensions | 1,219 × 1016 × 1,168mm (W × D × H) |
| Pallet format | US 48" × 40" composite |
| Pallet base height | 168mm (includes feet/runners) |
| Cage upright tube | Ø25mm |
| Cage top rail | 25mm OD |
| Drain valve | DN50 butterfly valve, S60×6 thread |
| Fill | side entry near the top (no top-cap access — only 52mm headroom stacked) |
| Tare weight | ~65 kg per tote |
| Full weight (1,000 L) | ~1,065 kg per tote |
| Total tare (4 totes) | ~260 kg; water load see weight-distribution report |
2.2 Tote Assignments¶
| Tote | Position | Circuit | Function |
|---|---|---|---|
| IBC-1 | Top tier, near column | Blue (clean supply) | Primary clean water supply for spray bar |
| IBC-2 | Top tier, far column | Blue (clean supply) | Secondary supply, filled in parallel with IBC-1 from the X1 fill tee |
| IBC-3 | Bottom tier, near column | Brown (recycled) | Wash water buffer — filtered and recycled back to Blue |
| IBC-4 | Bottom tier, far column | Black (waste) | Contaminated water sealed for off-site disposal |
2.3 Layout¶
| Parameter | Value |
|---|---|
| Near column Yd | 30–1,046mm (pushed to near/pinhole wall, 30mm clearance) |
| Far column Yd | 1,316–2,332mm (pushed to far wall, 30mm clearance) |
| Column X range | 4,674–5,893mm (right-justified to sealed end wall) |
| Plumbing corridor | Yd=1,046–1,316mm (270mm gap between columns) |
| Single IBC height | 1,168mm |
| Stacked height (2 totes, direct-stack cage-on-cage) | 2,336mm (2 × 1,168mm — no deck/mat between tiers) |
| Ceiling clearance | 52mm (2388 − 2,336mm) — tight but transport-validated (see weight report) |
3. Stacking Frame — Restraint-Only Deep 4-Leg Box¶
3.1 General Arrangement¶
The 1,000L caged totes direct-stack cage-on-cage — the upper tote's pallet base bears directly on the lower tote's cage top, leaving only 52mm of ceiling headroom. There is no room for (and no need for) a load-bearing platform deck between tiers, so the frame is restraint-only: it carries no vertical service load, it only keeps the totes from moving during transport.
The frame is a deep 4-leg box at the IBC front, spanning the plumbing corridor: a front pair of full-height 50×50×3 RHS uprights at the corridor mouth and a back pair ~450mm behind, tied by butt-jointed top and bottom rings, on four floor-flange feet (the front feet reach ~25mm under the tray edge). Transport restraint is provided by:
- front retaining bars across each column at the IBC front that stop the totes sliding out the open front, their wall ends dropped into Simpson-style joist hangers;
- D-ring lashing holders on the front bars, with ratchet straps over each stack;
- the totes are otherwise trapped by the container side walls (30mm gap) and sealed end wall.
The box carries the Corridor Plumbing Panel (pumps) and its drain-riser backing spine on the back uprights, and gives the right-walkway cantilever arms their clamp point on the front uprights.
3.2 Frame Specification¶
| Parameter | Value |
|---|---|
| Material | 50 × 50 × 3mm RHS mild steel (A500 Grade B) |
| Uprights | 4 full-height (deep 4-leg box: front pair at the corridor mouth + back pair ~450mm behind), tied by butt-jointed top + bottom rings |
| Floor anchorage | 4 × 150 × 150 × 12mm flange-plate feet, 4 × M12 anchors each (front feet reach ~25mm under the tray) |
| Front retaining bars | 4 × 50×20×3 RHS at the IBC front (seated in the 25mm gap to the film rail), wall → upright per column |
| Wall joist hangers | 4 × Simpson-style U-pocket receiving the front-bar wall ends, through-bolted (4 × M12 each) to an exterior backing plate |
| Exterior backing plates | 4 × 100 × 135 × 8mm steel, on the outside of the container side walls (hex heads outside) — spread the totes' transport thrust into the thin corrugated wall so the bolts can't pull through |
| D-ring lashing | holders on the front bars, 1,100 kg WLL |
| Panel mount | the box carries the Corridor (pump) Plumbing Panel + drain-riser spine on the back uprights, and the right-walkway cantilever arms on the front uprights |
| Frame weight | ~90 kg (4 uprights + rings + 4 feet + front bars + hangers + exterior plates + rear-panel brackets — see weight report) |
| Joints | Welded (fillet weld throughout) |
3.3 Direct-Stack Junction¶
The upper tote bears directly on the lower tote's galvanized cage top rail (no platform, mat or lip) — the totes' normal warehouse cage-on-cage stacking interface, rated for a full upper tote.
3.4 Structural Validation (restraint)¶
The frame carries no vertical service load (the totes stack on themselves), so there is no platform-beam bending case. The governing check is transport restraint: the front retaining bars + D-ring lashing must resist the totes' inertia under braking/cornering (loaded mass 5,044 kg, worst-case CG at Z=1,345mm — see the weight-distribution report).
- Front retaining bars (50×20×3 RHS) span wall→upright (~1,046mm) and take each tote's longitudinal (−X) thrust into the floor feet + wall hangers.
- Wall joist hangers receive the bar wall ends and are through-bolted (4 × M12) to a 100×135×8mm exterior backing plate on the outside of each side wall — the plate spreads the bolt load so the thin corrugated wall cannot pull through under the totes' thrust.
- D-ring lashing (1,100 kg WLL each) over each stack provides vertical tie-down and supplements lateral restraint; the totes are otherwise wall-trapped.
- Floor feet (150×150×12, 4 × M12 each) anchor the uprights against uplift and transfer the lateral loads into the slab.
4. Securing for Transport¶
4.1 D-Ring Lashing Points¶
| Parameter | Value |
|---|---|
| Quantity | 8 total (4 per tier) |
| Type | 25mm welded D-ring on 6mm mounting plate |
| Working load limit | 1,100 kg per ring |
| Mounting | Fillet-welded to the front retaining bars |
| Supplier | McMaster-Carr #3641T29 |
4.2 Ratchet Straps¶
| Parameter | Value |
|---|---|
| Type | 25mm ratchet strap |
| Working load limit | 1,100 kg |
| Routing | D-ring to D-ring, over IBC top, 1 strap per tier per side |
| Total straps | 4 (2 per tier) |
| Pre-transport | Tighten all straps; re-check tension after 50 km |
4.3 Wall Trapping¶
There is no anti-rotation lip. The direct-stacked totes are trapped laterally by the container side walls (30mm gap each side) and the sealed end wall; the front retaining bars + D-ring ratchet straps restrain the open front and provide vertical tie-down. Together these restrain both tiers in all six DOF.
5. Drain Valve Access¶
The bottom-tier drain valves (DN50 butterfly, corridor-facing) are reached directly from the open corridor front — with the Corridor Plumbing Panel moved forward and no load-bearing base frame, there are no removable access gates. The operator reaches in from the right walkway.
6. External Bulkhead Ports¶
Three 2" NPT bulkhead ports penetrate the sealed end wall on the container centerline — X1 (Blue fill), X3 (Brown drain), and X4 (Waste drain) — so all four totes fill and drain without opening the cargo doors. X1 gravity-feeds an internal tee that side-enters both Blue totes near the top, so one external hose fills both. Each penetration is backed by a welded wall reinforcing plate that spreads its load into the corrugated wall (the same approach as the frame's exterior backing plates, §3.2).
The port elevations are the diagram-of-record (see §8 Sheet 3). The bulkhead fittings, camlock, and seals are specified in the Water System Report §5 and §7; the bulkhead BOM, including the reinforcing plates, is in the master shopping list. (These end-wall ports are distinct from the two equipment Plumbing Panels — Corridor and Pinhole Wall — in §7.)
7. Internal Plumbing¶
All internal supply and return lines route through the 270mm plumbing corridor between the near and far IBC columns, reaching each tote's corridor-facing DN50 butterfly valve (S60×6 thread). The pipe specification, the per-circuit routing (X1 Blue gravity-fill teed to both top totes, X3 Brown and X4 Waste pumped drains, and the recycle returns), and the valve schedule are specified in the Water System Report §4–§5 and §7. The pumps and diverter valves that drive those circuits — on the Corridor Plumbing Panel (plywood, at the front (cargo-door) mouth of the corridor, bolted to the deep-box frame, see §3.2) — together with the 3-stage filter bank on the Pinhole Wall Plumbing Panel are specified in the Plumbing Report. This report treats the corridor plumbing and both panels only as loads the stacking frame carries.
8. Engineering Drawings¶
Eight construction drawings cover the IBC system across two drawing sets. They are shown inline in the relevant sections above; the full set is collected here and in Engineering Diagrams.
IBC Stacking & Securing (5 sheets)¶
Sheet 1 — Cross-section elevation: 2-tier direct-stack, restraint deep 4-leg box, front retaining bars + wall hangers, direct-stack junction, 52mm clearance
Sheet 2 — Fastening details: front-bar→upright cleat + lash eye, wall joist hanger, ratchet lashing over the stack
Sheet 3 — External bulkhead ports: Sealed end wall elevation with 3× ports
Sheet 4 — Internal plumbing plan view: IBC layout, pipe routing, valves, Corridor Plumbing Panel
Sheet 5 — Internal plumbing elevation: Pipe routing from IBCs to bulkhead unions
IBC Support Frame Fabrication (3 sheets)¶
Sheet 1 — Front elevation: deep-box uprights (front pair, back pair 450mm behind), floor feet, front retaining bars + wall hangers + D-ring holders, direct-stack junction
Sheet 2 — Side elevation: deep 4-leg box (front + back uprights + top/bottom rings) + front bars (end-on) + walkway cantilever arm
Sheet 3 — Plan view: deep 4-leg box (4 legs + ring perimeter) + retaining bars + 4 floor feet + IBC footprints + corridor + walkway arms
Full drawings also appear in Engineering Diagrams §15 (stacking) and §17 (frame fabrication).
9. Parts List¶
9.1 Stacking Frame¶
| Item | Spec | Qty | Supplier | Est. cost |
|---|---|---|---|---|
| 50 × 50 × 3mm RHS mild steel (6 m lengths) | Deep 4-leg box uprights (front + back pair) + top/bottom rings + front retaining bars + panel-mount rail (~19.5 m) | 4 ea | Metal Supermarkets | $120–$180 |
| 12mm steel plate, 150 × 150 cut | Deep-box upright floor flange feet (one per leg; front feet reach under the tray) | 4 ea | Metal Supermarkets | $20–$40 |
| 4mm folded plate | Simpson-style wall joist hangers | 4 ea | Local fab | $30–$50 |
| 25mm welded D-ring (3641T29) | Lashing holders on the front bars (4 per tier × 2 tiers), 6mm mount plates | 8 ea | McMaster-Carr | $40–$70 |
| 25mm ratchet strap, 1,100 kg WLL | Transport securing, over each stack | 4 ea | Amazon | $30–$50 |
| M12 floor anchor (wedge/sleeve, container floor) | 4 deep-box flange feet × 4 anchors each | 16 ea | McMaster-Carr | $30–$60 |
| M12 × 40 bolt, Grade 8.8 | Wall hangers (2 each) + front-bar cleats | 12 ea | McMaster-Carr | $12–$22 |
| Welding / fabrication (frame assembly) | ~14–20 hrs labor (deep 4-leg box — the ring/back-upright welds sit at the upper end of the range) | 1 lot | Local fab | $688–$1,018 |
| Primer + paint | Anti-corrosion coating | 1 lot | Hardware store | $30–$50 |
| Ibc-Frame total | $1,000–$1,540 |
9.2 IBC Totes¶
| Item | Specification | Qty | Est. cost (USD) |
|---|---|---|---|
| 1,000 L caged composite IBC tote (Schütz Ecobulk MX 1000 or equiv.) | New or reconditioned US 48×40 caged composite (~65 kg) | 4 | $300–$900 |
| IBC subtotal | $300–$900 |
The corridor and bulkhead plumbing parts (pipe, valves, fittings, camlock, bulkhead unions, reinforcing plates) are budgeted in the Water System Report §8 and the master shopping list, not here — this BOM covers only the stacking structure and the totes it restrains.
9.3 Cost Summary¶
| Assembly | Low estimate | High estimate |
|---|---|---|
| Stacking frame (restraint deep 4-leg box) | $1,000 | $1,540 |
| IBC totes (4×) | $300 | $900 |
| Total | $1,280 | $2,405 |
10. Maintenance Schedule¶
| Interval | Task |
|---|---|
| Every use | Visually inspect ratchet strap tension before transport |
| Every 10 prints | Inspect IBC valve seals (DN50 butterfly) for drips; tighten or replace O-ring |
| Every 10 prints | Check external camlock fittings for cross-threading; clean dust caps |
| Every 6 months | Inspect D-ring welds for cracking; load-test straps |
| Every 6 months | Inspect D-ring holders + ratchet straps for wear; re-tension straps |
| Annually | Inspect frame welds (all joints) for fatigue cracking |
| Annually | Touch up paint on frame where chipped or rusted |
| Annually | Inspect front-bar/wall-hanger bolts and upright floor-anchor bolts for loosening; re-torque to spec |
| Annually | Flush all internal pipes with clean water; inspect for biofilm |
| As needed | Replace camlock gaskets if leaking |
| As needed | Clean IBC interiors between circuit changes (bleach rinse + water flush) |
11. Sources¶
| Item | Source |
|---|---|
| Schütz Ecobulk MX 1000 L IBC | Schütz product catalog — US 48×40 composite tote, DN50 valve, UN31HA1/Y (all four totes are this size; "600 L"/"640 L" are fill levels, not tote sizes) |
| D-ring lashing point | McMaster-Carr #3641T29 — 25mm, 1,100 kg WLL |
| Plumbing fittings, pipe, valves, camlock, pumps | Specified and sourced in the Water System Report §11 and Plumbing Report §11 |
| Water system architecture | Water System Report §3 |
| IBC layout and stacking | Equipment Layout Report §5 |
| Frame fabrication drawings | §8 — Engineering Drawings (this report) · All Diagrams |
| Plumbing panel specification | Plumbing Report |