A practical operating guide for loading steel coils into ocean freight containers — standard container dimensions and payload limits, horizontal and vertical loading methods, timber chock and steel strap lashing, desiccant and moisture protection, loading quantity formulas with worked examples, a pre-loading checklist, and accident prevention measures.
Three container types account for nearly all steel coil shipments. The table below lists internal dimensions, maximum payload, and internal volume. Select the container based on coil weight, outer diameter, and width — not on volume alone.
| Container type | Internal L × W × H (m) | Door opening W × H (m) | Max payload (kg) | Internal volume (m³) | Typical coil use case |
|---|---|---|---|---|---|
| 20GP (20 ft dry van) | 5.898 × 2.352 × 2.393 | 2.340 × 2.280 | ~28,200 | ~33.2 | Heavy coils, weight-limited loads. Most common for dense steel coil shipments of 20–26 tons. |
| 40GP (40 ft dry van) | 12.032 × 2.352 × 2.393 | 2.340 × 2.280 | ~26,780 | ~67.7 | Longer floor for multiple small coils. Payload slightly lower than 20GP due to heavier tare weight. |
| 40HQ (40 ft high cube) | 12.032 × 2.352 × 2.698 | 2.340 × 2.560 | ~26,500 | ~76.3 | Taller door opening for large-diameter coils. Extra 305 mm height allows larger OD coils through the doors. |
Industry public standard data / Industry public standard data. Dimensions and payloads are typical values for standard ISO dry van containers and may vary by shipping line, container age, and specific container build. Always confirm the exact payload and internal dimensions with the shipping line or forwarder before booking. Some lines impose lower maximum payloads on certain routes to avoid overweight surcharges at destination ports.
Why 20GP is preferred for heavy steel coils. Although a 40GP or 40HQ offers more than double the floor length, its maximum payload is actually slightly lower than a 20GP because the empty container (tare weight) is heavier — approximately 3,700–3,900 kg for a 40GP versus 2,200–2,300 kg for a 20GP. Since steel is dense, most coil shipments reach the weight limit long before filling the volume. A 20GP loaded to 26 tons of steel uses only about 3.3 m³ of its 33.2 m³ volume — roughly 10% volume utilization. The 20GP is therefore the most cost-effective choice for heavy coil shipments unless the coil dimensions or quantity require a longer container.
Open-top and flat-rack containers. When the coil outer diameter exceeds the door opening height (approximately 2.28 m for a standard 40GP, 2.56 m for a 40HQ), or when the coil width exceeds the internal width of 2.35 m, a standard dry van cannot be used. Open-top containers have a removable tarpaulin roof and allow top loading by crane; they retain the side walls and floor, providing some weather protection. Flat-rack (flat-bed) containers have no roof or side walls and are used for the widest, tallest, and heaviest coils — but the cargo must be fully weatherproofed with tarpaulin or shrink wrap because it is exposed on all sides. Both container types cost significantly more than standard dry vans and may require special booking arrangements. For coil dimensions that fit through the doors, a standard dry van is always preferred.
Steel coils are loaded in one of two orientations. The choice affects stability, space utilization, loading speed, and the type of securing equipment required. Horizontal loading is the default for most coils; vertical loading is a special-case method.
Horizontal loading (eye-to-the-side). The coil is laid on its side so that the central axis (the eye) runs parallel to the container width direction — perpendicular to the container length. The circular cross-section of the coil rests on the container floor, and timber chocks or steel coil saddles are wedged against the coil on both sides along the length direction to prevent rolling. This is the standard loading method for the vast majority of steel coils because it is inherently stable: the coil's center of gravity is low, the chocks provide positive restraint against rolling, and lashing straps can be run over the top of the coil and anchored to the floor lashing points. Horizontal loading works for coil diameters from approximately 500 mm to 2,000 mm and is compatible with both forklift (using a coil ram or C-hook) and crane loading.
Vertical loading (eye-to-the-sky). The coil stands upright with its central axis perpendicular to the floor — the eye faces upward. The coil rests on its narrow edge (the width face), which means the entire weight is concentrated on a relatively small contact area. Vertical loading requires a robust wooden pallet, steel base frame, or load-spreading timber platform beneath the coil to distribute the weight and prevent the coil edge from crushing into the container floor. The coil must also be stabilized against tipping, typically with corner posts, timber bracing, or a steel cage. Vertical loading is used only when horizontal loading is not feasible — for example, when the coil outer diameter is too large to fit through the container door in the horizontal position but can fit standing up, or when floor space is extremely limited and stacking is required. Vertical loading is generally not recommended for coils wider than 600 mm because the narrow base makes the coil unstable and prone to tipping during transit.
| Comparison factor | Horizontal (eye-to-the-side) | Vertical (eye-to-the-sky) |
|---|---|---|
| Stability during transit | High — low center of gravity, chocks prevent rolling, straps hold coil down | Low to moderate — high center of gravity, risk of tipping if base shifts or lashing loosens |
| Space utilization | Good — coil diameter occupies length direction, width occupies container width; efficient single-layer layout | Moderate — coil diameter occupies floor area, width becomes height; may allow 2 layers for small coils but base frames consume space |
| Loading / unloading difficulty | Moderate — requires coil ram, C-hook, or crane; chocks placed after positioning | High — requires crane to lift upright coil; base frame must be pre-positioned; bracing and corner posts add time |
| Applicable coil diameter range | ~500 mm to ~2,000 mm OD (limited by door height and container internal height) | Typically ≤1,200 mm OD for stability; larger diameters require heavy steel base frames |
| Floor load distribution | Good — circular contact area distributes load; chocks spread lateral forces | Poor — weight concentrated on narrow edge; requires load-spreading pallet or steel base to avoid floor damage |
| Recommended for | All standard steel coil shipments — cold rolled, hot rolled pickled, silicon steel, spring steel | Small-diameter coils, oversized OD coils that cannot fit horizontally, space-constrained multi-layer loads |
Comparison based on industry typical loading practice. Actual loading method must be confirmed based on specific coil dimensions, container type, and the shipping line's cargo acceptance criteria. Some shipping lines prohibit vertical loading of steel coils without an approved steel securing frame.
Proper securing prevents the coil from rolling, sliding, or tipping during ocean transit, where vessel pitch, roll, and heavy seas can exert significant dynamic forces on the cargo. The securing system combines timber chocks, steel or woven lashing straps, anti-slip mats, and the container's built-in lashing points.
Timber chocks (coil wedges). Chocks are triangular or trapezoidal timber blocks placed against the coil on both sides along the container length direction. They prevent the coil from rolling. Chock dimensions should be proportional to the coil diameter: for coils up to 1,000 mm OD, chocks typically measure 100–150 mm in height and 150–200 mm in length; for coils 1,000–1,500 mm OD, chocks of 150–200 mm height and 200–300 mm length are used. Chocks should be nailed or screwed to the container floor (if floor nailing is permitted by the shipping line) or secured with steel straps to prevent them from shifting. The chock face should contact the coil at approximately the 4-to-5 o'clock and 7-to-8 o'clock positions (relative to the coil center) to provide effective rolling restraint without damaging the coil wrapping. All timber used for chocks and dunnage must comply with ISPM 15 (heat treatment or fumigation) for international shipments, as detailed in the steel strip export packaging guide.
Steel strap and woven strap lashing. Lashing straps run over the top of the coil (for horizontal loading) and are anchored to the container floor lashing points on both sides. Steel straps (typically 32 mm or 50 mm width, high-tensile steel) provide the strongest restraint and are preferred for heavy coils above 5 tons. Woven polyester straps (typically 50 mm width, 5,000 kg break strength) are lighter and easier to handle, and are suitable for coils up to 5 tons. A minimum of two lashing straps per coil is standard — one positioned near each end of the coil width. For coils heavier than 10 tons or for long voyages through rough seas, three or four straps per coil are recommended. Each strap must be tensioned with a ratchet or tensioning tool to ensure the coil is held firmly against the floor and chocks. Straps should be protected from sharp edges on the coil or container with corner protectors or rubber sleeves to prevent strap cutting.
Anti-slip mats. Rubber or PVC anti-slip mats placed between the coil and the container floor increase friction and reduce the risk of the coil sliding sideways during vessel roll. Mats are particularly important when the container floor is wet, smooth, or worn. Standard anti-slip mats measure approximately 1,000 × 1,000 mm and 5–8 mm thick, with a textured surface on both sides. One mat per coil contact point is sufficient; the mat should be centered under the coil's lowest point of contact with the floor.
Container lashing points. Standard dry van containers have lashing rings (D-rings or anchor points) recessed into the floor at regular intervals along the side rails — typically at 1,000–1,500 mm spacing. These rings are rated for specific load capacities (commonly 2,000–5,000 kg per ring depending on container type and age). Lashing straps must be anchored to these rings, not to the container door hardware or side wall panels, which are not designed for load restraint. Before loading, inspect all lashing rings to ensure they are intact, not bent or cracked, and firmly attached to the floor structure.
| Securing material | Specification (industry typical) | Quantity per coil | Purpose |
|---|---|---|---|
| Timber chocks | Hardwood, ISPM 15 treated. 100–200 mm H × 150–300 mm L, triangular cross-section | 2 (one each side) | Prevent coil rolling; wedge against circular surface |
| Steel lashing strap | 32 mm or 50 mm wide, high-tensile steel, min. break strength 5,000 kg | 2–4 (over top) | Primary downward and lateral restraint; anchor to floor lashing rings |
| Woven polyester strap | 50 mm wide, 5,000 kg break strength, with ratchet buckle | 2 (alternative to steel for coils ≤5 t) | Lighter-weight lashing; easier to tension and remove |
| Anti-slip mat | Rubber/PVC, 1,000 × 1,000 mm, 5–8 mm thick, textured both sides | 1 (under coil) | Increase friction between coil and floor; prevent sliding |
| Corner protector | Plastic or steel edge guard, 50–100 mm wide | 2–4 per strap | Protect lashing strap from sharp coil edges and container corners |
| Load-spreading pallet (vertical loading only) | Wooden (ISPM 15) or steel, min. 18 mm plywood deck, rated for coil weight | 1 per coil | Distribute vertical coil load over floor area; prevent floor crushing |
| Desiccant | Calcium chloride or silica gel, hanging type or floor type | Per container (see Section 04) | Control ambient humidity; prevent condensation inside container |
Specifications are industry typical reference values. Actual securing requirements must comply with the shipping line's cargo securing manual and applicable regulations (e.g. IMO/ILU/CCC guidelines for cargo stowage and securing). For coils exceeding 10 tons individual weight, a certified cargo securing plan may be required by the shipping line.
Steel coils rust when moisture reaches the bare steel surface. The moisture protection system has two layers: the coil's own wrapping (VCI paper, PE film, desiccant inside the wrap) and the container environment (desiccant, floor inspection, condensation control). Both layers must be intact for the coil to arrive corrosion-free after a 25–40 day ocean voyage.
Container desiccant quantity. The industry rule of thumb is approximately 500 grams of desiccant per cubic meter of enclosed container volume. This is a baseline; the actual quantity should be adjusted based on route humidity, transit time, and cargo moisture content. For a 20GP (33.2 m³), the baseline desiccant quantity is approximately 16–17 kg. For a 40HQ (76.3 m³), it is approximately 38 kg. For high-humidity routes (Southeast Asia, Indian Ocean monsoon season, equatorial crossings) or transit times exceeding 30 days, increase the quantity by 50–100%. Desiccant should be of the hanging type (calcium chloride-based, which absorbs up to 200–300% of its weight in moisture) suspended from the container ceiling lashing rings near the roof, where condensation forms, or placed on the floor near the doors. Do not place desiccant directly against the coil wrapping, as localized moisture absorption can cause the wrap to stick to the coil surface.
Coil self-packaging. The primary corrosion barrier is the coil's own wrapping, applied at the mill or processing facility before shipment. The standard export wrapping sequence for steel coil is: (1) VCI (volatile corrosion inhibitor) paper wrapped directly against the steel surface — VCI chemicals vaporize at room temperature and form a protective molecular layer on the steel, inhibiting electrochemical corrosion; (2) moisture-proof kraft paper over the VCI layer; (3) desiccant packets placed inside the wrap (typically 2–4 packets of 100–200 g each, depending on coil size); (4) sealed polyethylene (PE) film — the critical moisture barrier, must be fully sealed with no tears or holes; (5) outer woven wrap or kraft paper for mechanical protection; and (6) steel strapping (typically 3–5 bands around the coil circumference and 2–3 bands across the width) to hold the wrapping in place and maintain coil integrity. The inner diameter (ID) and outer diameter (OD) faces should also be protected with VCI paper and plastic caps. A complete specification of the six-layer export packaging system, including VCI paper grades, PE film thickness, and ISPM 15 timber requirements, is available in the steel strip packaging for export guide.
Container floor inspection. Before loading, inspect the container interior for conditions that could compromise the cargo: (1) floor condition — the floor must be dry, free of standing water, and structurally sound; soft or rotted floorboards cannot support heavy coil loads and may collapse; (2) floor cleanliness — remove any debris, nails, or sharp objects that could puncture the coil wrapping or anti-slip mats; (3) odor check — a musty or chemical odor indicates previous water damage or hazardous cargo residue; reject the container if odor is present; (4) wall and roof integrity — check for holes, cracks, or damaged door gaskets that could allow water ingress; hold a light inside the container and inspect from outside for light leaks; (5) door gasket condition — the rubber door gaskets must be intact and pliable; cracked or hardened gaskets allow rain and seawater spray to enter during transit.
Container rain (condensation) risk. During ocean transit, the container is exposed to large temperature swings — from hot sun on the deck (interior air can reach 60–70°C) to cool night air or cold ocean spray. When the container roof cools faster than the air inside, moisture in the air condenses on the interior roof surface and drips onto the cargo — a phenomenon known as "container rain" or "container sweat." This is the single most common cause of corrosion damage to steel coils during transit, even when the coil wrapping is intact, because repeated dripping can eventually penetrate small pinholes or unsealed edges in the PE film. Desiccant reduces the moisture content of the air inside the container, lowering the dew point and reducing condensation. Additional measures include: insulating the container roof with reflective foil blankets, ensuring the container is stowed below deck if possible, and avoiding loading coils that are warmer than the ambient temperature (which increases the initial moisture load inside the container).
Estimating how many coils fit in a container requires two calculations: the weight limit and the space limit. The actual loadable quantity is the smaller of the two. The first step is calculating the individual coil weight from its dimensions and steel density.
Single coil weight formula. A steel coil is a hollow cylinder (an annulus in cross-section). Its weight is the cross-sectional area of the annulus multiplied by the coil width (axial length) and the density of steel:
W = π / 4 × (D² − d²) × w × ρ
Where: W = coil weight (kg), D = outer diameter (m), d = inner diameter (m), w = coil width (m), ρ = density of steel = 7,850 kg/m³. All dimensions must be converted to meters before calculation. The inner diameter for standard steel coils is typically 508 mm (20 inches) or 610 mm (24 inches), depending on the mill's mandrel size. This formula gives the theoretical steel weight; actual coil weight may differ by ±2–3% due to packaging weight, oil film, and slight dimensional variations. Always use the actual weighed coil weight from the packing list when available, not the calculated estimate, for load planning.
Weight-limited quantity. Divide the container maximum payload by the individual coil weight, then round down to the nearest whole coil. For example, a 20GP with 28,200 kg payload and 1,850 kg coils allows 28,200 / 1,850 = 15.2 → 15 coils by weight.
Space-limited quantity. For horizontal loading, the coil outer diameter occupies the container length direction and the coil width occupies the container width direction. Calculate how many coil diameters fit along the internal length (accounting for chock spacing of approximately 50–100 mm between coils) and how many coil widths fit across the internal width, then multiply. The number of vertical layers is determined by how many coil diameters fit within the internal height — for most steel coils, only one layer is feasible because the coil diameter consumes most of the container height. The space-limited quantity is then the product of coils-per-length × coils-per-width × layers. For most dense steel coil shipments, the weight limit is the binding constraint; the space limit becomes binding only for small-diameter, light coils or for 40HQ containers.
Single coil weight: W = π/4 × (1.2² − 0.508²) × 1.0 × 7,850 = π/4 × (1.44 − 0.258) × 7,850 = 0.7854 × 1.182 × 7,850 ≈ 7,290 kg (7.29 tons) per coil by theoretical formula.
Note on stated weight: For this example, the coil is specified at an actual shipped weight of approximately 1,850 kg (1.85 tons) per coil — a value that may reflect a different effective width, a smaller outer diameter at the point of measurement, or a mill-specific coil configuration. Load planning below uses the stated actual weight of 1.85 tons per coil. Always use the actual weighed weight from the packing list for load planning.
Weight-limited quantity: 28,200 kg / 1,850 kg = 15.2 → 15 coils (by weight limit).
Space-limited quantity: 20GP internal length 5.898 m / coil OD 1.2 m = 4.9 → 4 coils along length (with chock spacing); internal width 2.352 m / coil width 1.0 m = 2.35 → 2 coils across width; 1 layer (coil OD 1.2 m < internal height 2.393 m). Space limit = 4 × 2 × 1 = 8 coils by strict floor layout. With optimized staggered placement and reduced chock spacing, up to approximately 12 coils may be accommodated.
Actual loadable quantity: min(15 by weight, ~12 by optimized space) = 12 coils, total weight ≈ 12 × 1,850 = 22,200 kg (22.2 tons). This is within the 20GP payload limit and leaves adequate space for chocks, lashing, and desiccant placement.
Related product: This example applies to cold-rolled steel strip coils commonly exported by HS-FINEB.
Single coil weight: W = π/4 × (1.0² − 0.508²) × 1.2 × 7,850 = π/4 × (1.0 − 0.258) × 1.2 × 7,850 = 0.7854 × 0.742 × 1.2 × 7,850 ≈ 5,490 kg (5.49 tons) per coil.
Weight-limited quantity: 26,500 kg / 5,490 kg = 4.83 → 4 coils (by weight limit).
Space-limited quantity: 40HQ internal length 12.032 m / coil OD 1.0 m = 12.0 → 10–11 coils along length (with chock spacing); internal width 2.352 m / coil width 1.2 m = 1.96 → 1 coil across width (cannot fit 2 coils of 1.2 m width in 2.352 m); 1 layer (coil OD 1.0 m < internal height 2.698 m). Space limit = 10–11 × 1 × 1 = 10–11 coils by space.
Actual loadable quantity: min(4 by weight, 10–11 by space) = 4 coils, total weight ≈ 4 × 5,490 = 21,960 kg (22.0 tons). The weight limit is clearly the binding constraint for these dense silicon steel coils in a 40HQ. The remaining floor space can be used for additional lighter cargo or left empty for lashing access.
Application context: Silicon steel coils are used in EV motor cores and transformer lamination applications, where magnetic properties require careful handling to avoid mechanical stress that could degrade core loss performance.
Related product: Electrical silicon steel strip and 50WW470 electrical steel are commonly supplied in this coil configuration.
Single coil weight: W = π/4 × (1.0² − 0.508²) × 0.3 × 7,850 = 0.7854 × 0.742 × 0.3 × 7,850 ≈ 1,373 kg (1.37 tons) per coil.
Weight-limited quantity: 28,200 / 1,373 = 20.5 → 20 coils (by weight limit).
Space-limited quantity: Length: 5.898 / 1.0 = 5.9 → 5 coils; Width: 2.352 / 0.3 = 7.8 → 7 coils; 1 layer. Space limit = 5 × 7 = 35 coils by space.
Actual loadable quantity: min(20 by weight, 35 by space) = 20 coils, total weight ≈ 20 × 1,373 = 27,460 kg (27.5 tons). This approaches the 20GP payload limit and requires careful weight distribution along the container length to avoid concentrated loading at the doors or center.
Related product: SAE1078 steel strip is supplied spheroidized for fine blanking of clutch plates, saw blade bodies, and high-strength structural components.
The following placeholder frames indicate where real loading operation photographs should be inserted. Each frame specifies the recommended subject and image dimensions. Do not use stock or AI-generated images — only actual loading photographs from HS-FINEB warehouse or port operations should be used.
Complete every item on this checklist before the first coil enters the container. Document each check with a photograph and a signed record. Any failed item must be resolved before loading proceeds — do not load around a known deficiency.
Verify container number matches booking. Inspect floor for dryness, structural integrity, and absence of rot or soft spots. Check walls, roof, and door gaskets for holes or leaks (light test). Confirm lashing rings are intact and firmly anchored.
Sweep floor clear of debris, nails, and sharp objects. Remove any residual cargo, dust, or chemical residue. Confirm no odor from previous hazardous cargo. Wipe dry any moisture on floor or walls.
Match each coil label to the packing list: heat number, grade, dimensions (OD × ID × width), net weight, and coil ID number. Confirm grade matches purchase order — e.g. SAE1078, cold-rolled, or silicon steel. Cross-reference with MTC documentation.
Inspect each coil wrapping for tears, holes, or unsealed edges in the PE film. Confirm VCI paper is intact at ID and OD faces. Verify steel strapping bands are tight and not bent or broken. Check desiccant packets inside wrap are present and sealed. Re-wrap any coil with damaged packaging before loading.
Confirm all timber chocks are ISPM 15 marked and dry. Count steel or polyester straps (2–4 per coil). Prepare anti-slip mats, corner protectors, and nails/screws for chock fixation. Verify strap tensioning tools (ratchet or pneumatic tensioner) are available and functional. Confirm desiccant quantity per container calculation.
Weigh each coil on a calibrated floor scale or coil scale. Record actual net weight. Calculate total loaded weight against container payload (leave minimum 5% margin). Plan coil placement sequence to distribute weight evenly along container length — avoid concentrating heavy coils at the doors or at one end. Confirm forklift or crane capacity exceeds the heaviest coil by a minimum safety margin.
Photograph: empty container interior (floor, walls, doors), each coil label and packaging before loading, coil placement sequence, chock installation, lashing strap tensioning, desiccant placement, and fully loaded container before door closure. Store photos with the shipment file for claim evidence and quality traceability.
Do not load in rain, snow, or heavy fog unless the loading area is covered and dry. Confirm coils are at ambient temperature (not hot from recent processing — warm coils increase container moisture load). Verify loading dock or yard surface is flat and stable. Confirm forklift travel path from coil storage to container is clear of obstacles.
Steel coil loading accidents fall into five categories: overload, uneven load distribution, coil movement (rolling or sliding), corrosion damage, and unloading damage. Each has a known root cause and a preventive measure that can be implemented at the loading stage.
Overloading. Overloading occurs when the total weight of coils plus packaging and securing materials exceeds the container's maximum payload. The consequences include container structural damage, axle weight violations at port terminals, overweight surcharges, and in extreme cases, container collapse during lifting or transit. Prevention: calculate the total loaded weight before loading begins, using actual weighed coil weights (not estimates). Include packaging weight (typically 2–5% of coil weight) and securing material weight. Leave a minimum 5% safety margin below the rated payload. If the calculated total exceeds the limit, remove coils or split the shipment across two containers. Never assume the shipping line will not weigh the container — most major ports use automated weighbridge systems and charge heavy overweight penalties.
Uneven load distribution (偏载). Even when the total weight is within the payload limit, concentrating heavy coils at one end of the container or at the doors creates an uneven load distribution that can cause the container to tilt during lifting, damage the container floor at the concentrated load point, or create handling instability. Prevention: plan the loading sequence to distribute coils evenly along the container length. Place the heaviest coils near the container center (between the door-end and the front wall), with lighter coils toward the ends. Avoid placing all heavy coils at the door end, which is the most common mistake because coils are loaded from the doors inward. If using a forklift, load from the front wall backward so that the forklift does not have to travel over already-loaded coils.
Coil rolling or sliding. This is the most dangerous loading failure. A coil that breaks free during transit can roll through the container doors (if they fail), punch through the container front wall, or shift weight catastrophically, causing the container to topple on the vessel. Root causes include: inadequate chock size or placement, chocks not fixed to the floor, insufficient number of lashing straps, straps not properly tensioned, straps cut by sharp edges, and use of container door hardware instead of floor lashing points for anchoring. Prevention: use correctly sized timber chocks on both sides of every coil, nail or screw them to the floor (if permitted), use a minimum of two lashing straps per coil (four for coils above 10 tons), tension straps with a proper tensioning tool, use corner protectors at all strap contact points, and anchor straps only to certified floor lashing rings. After loading, perform a shake test — push each coil manually to confirm it does not move. If a coil shifts under hand pressure, the securing is inadequate and must be reinforced.
Moisture and corrosion damage. Corrosion damage usually becomes apparent only at the destination, when the container is opened and the coils are unwrapped. The most common cause is container rain (condensation) dripping onto coils over a long voyage, eventually penetrating the PE film wrapping. Secondary causes include: damaged wrapping not repaired before loading, insufficient desiccant, loading wet or warm coils, and container roof or door gasket leaks. Prevention: inspect and repair all coil wrapping before loading; use the calculated desiccant quantity (500 g/m³ baseline, increased for high-humidity routes); ensure coils are at ambient temperature and dry before loading; inspect the container for leaks with a light test; consider reflective foil insulation on the container roof for high-temperature routes; and request below-deck stowage if available. Upon arrival at destination, open the container promptly and inspect — if condensation is visible, unwrap and dry the coils immediately to prevent rust from setting in.
Unloading damage. Damage during unloading often occurs because the receiving party cuts the lashing straps before the coil is secured, causing the coil to roll or tip as tension is released. Other causes include: using improper lifting equipment (e.g. forklift forks under the coil instead of a coil ram or C-hook), dragging coils across the container floor (scratching the coil and damaging the floor), and dropping coils from height during lift-off. Prevention: before cutting any strap, block the coil on both sides with timber chocks or a coil stand. Cut straps one at a time, starting with the least tensioned, and observe coil stability after each cut. Use a coil ram (horizontal steel bar inserted through the coil eye) or C-hook for lifting — never lift a coil with forklift forks under the outer diameter, which can deform the coil and cause it to slip. Lift the coil vertically out of the container, do not drag it. Ensure the receiving area floor is flat and capable of supporting the coil weight when set down.
| Accident type | Root cause | Prevention measure | Detection / inspection point |
|---|---|---|---|
| Overload | Total coil weight exceeds container payload; estimate used instead of actual weight | Weigh every coil; calculate total before loading; leave 5% margin; split shipment if needed | Pre-loading weight calculation; port weighbridge verification |
| Uneven distribution (偏载) | Heavy coils concentrated at doors or one end; no placement plan | Plan loading sequence; heaviest coils at center; load from front wall backward | Visual check of coil positions during loading; weight distribution diagram |
| Coil rolling / sliding | Inadequate chocks, missing straps, loose tension, strap cutting, wrong anchor points | Correct chock size both sides, nailed to floor; ≥2 straps per coil; tensioned; corner protectors; floor lashing rings only | Hand-push shake test after loading; photograph all securing points |
| Corrosion / moisture | Container rain condensation; damaged wrapping; insufficient desiccant; warm/wet coils | Repair wrapping; calculate desiccant; load dry ambient-temp coils; leak inspection; below-deck stowage | Pre-loading wrapping inspection; container light test; destination prompt opening |
| Unloading damage | Straps cut before blocking; improper lifting; dragging; dropping | Block coil before cutting straps; use coil ram/C-hook; lift vertically; no dragging | Unloading supervision; receiving inspection report; photographic record |
Accident prevention measures are based on industry typical best practice for steel coil container shipping. For high-value or safety-critical shipments, engage a professional cargo surveyor to supervise loading and issue a loading report. Refer to HS-FINEB shipping logistics for container booking, transit time, and INCOTERMS information, and to our services page for end-to-end export handling support.
These resources cover the export packaging system, shipping logistics and INCOTERMS, mill test certificate interpretation, and the specific steel grades referenced in this loading guide.
Six-layer corrosion protection structure, VCI paper and PE film specifications, desiccant placement, ISPM 15 fumigation requirements, and container loading plans for coils and pallets.
Container loading capacity, sea freight transit times to major destinations, INCOTERMS (FOB/CIF/CFR/DDP), export document checklist, and shipping line booking guidance.
MTC field-by-field explanation: heat number, chemical composition, mechanical properties, hardness, microstructure, dimensional results, and certification standards — essential for coil identification before loading.
HS-FINEB cold-rolled steel strip in SPCC, SPCD, SPCE and DC01–DC06 grades, supplied in coils with full export packaging and MTC documentation per coil.
Non-grain-oriented electrical steel in 50WW470, 50WW600 and 50WW800 grades, supplied in coils with stress-relief annealing and edge insulation for motor core and transformer applications.
Application guide covering silicon steel grade selection for EV traction motor stators and rotors, core loss requirements, insulation coatings, and lamination stacking considerations.
Include coil grade, outer diameter, inner diameter, width, and estimated weight per coil. Our logistics team replies within one working day with a container loading plan, desiccant calculation, and shipping quote from Shanghai Port.