A Lined Drum is a steel drum with an internal corrosion-resistant lining, used for cargoes that require steel structural strength but would attack bare steel within hours or days. The drum body is the standard 1A1 closed-head or 1A2 open-head steel drum; the difference is an internal coating or insert that isolates the cargo from the steel wall. Common linings include phenolic epoxy, baked phenolic, polyethylene rotomoulded insert, and PTFE-coated steel. The lined drum extends the cargo-compatibility envelope to cover concentrated acids, peroxides, certain organic solvents, and food-grade or pharmaceutical-grade cargoes that need an inert contact surface.
Common lining types
| Lining | Cargo envelope | Cost premium per drum | Service life |
|---|---|---|---|
| Phenolic epoxy | Most aqueous corrosives, dilute acids, alkalis, food-grade liquids | USD 8-12 | 3-5 years with reconditioning |
| Baked phenolic | Concentrated acids (sulphuric to 96%, nitric to 60%), oxidisers, formaldehyde solutions | USD 12-20 | 5-7 years |
| Polyethylene rotomoulded insert | Aqueous corrosives, HDPE-compatible chemistry where steel structure is needed for stacking | USD 15-25 | 5-10 years (insert is replaceable) |
| PTFE coating | Aggressive oxidisers, fluorinated chemistry, ultra-high-purity cargoes | USD 25-50 | 7-10 years |
| Zinc-galvanised interior | Mild corrosives, some peroxides at low concentration | USD 4-8 | 2-3 years |
The choice is cargo-driven. A factory shipping concentrated nitric acid at 65% picks baked phenolic. A pharmaceutical buyer shipping high-purity solvents picks PTFE coating. A bulk caustic soda solution shipper either picks plain HDPE drums (no lining premium needed) or, for unusually heavy stacking requirements, phenolic-lined steel.
When lined drum is the right packaging
Lined drum is the right choice for:
- Concentrated acids that would corrode bare steel within days. Concentrated sulphuric, concentrated nitric, fuming sulphuric (oleum), strong phosphoric acid solutions.
- Oxidisers beyond the HDPE compatibility envelope. Hydrogen peroxide above 35%, peracetic acid solutions, concentrated hypochlorites at elevated temperature.
- Food-grade and pharmaceutical-grade cargoes that need traceable, non-reactive contact surface, most regulators specify FDA-compliant phenolic or PE insert for these cargoes.
- Cargoes shipped under high-stack-pressure handling where HDPE drums would deform but bare steel would corrode.
- Long-term storage applications where a 12+ month shelf life is needed and HDPE permeation would compromise the cargo.
Lined drum is the wrong choice for:
- Routine aqueous corrosives that ship perfectly well in HDPE drums at lower cost.
- Cargoes at elevated temperature where the lining adhesion can break down. Phenolic epoxy linings begin to delaminate above 80-90°C; cargoes above this temperature need direct steel or specialty PTFE.
- Solid cargoes where simple steel or fibre drums work without the lining cost.
The lining-failure failure mode
The single most common lined-drum failure on long sea routes is lining delamination from the steel wall. Three patterns:
- Over-temperature exposure during loading or transhipment. Cargo loaded at 70°C into a phenolic-lined drum ages the lining over the voyage; arrival inspection shows lining peel at the bung area where the temperature was highest.
- Mechanical impact during handling. A drum dropped during port handling can crack the lining without visible damage to the steel exterior. The cargo then contacts bare steel at the crack site and starts a corrosion cell that grows over weeks.
- Chemical attack at the lining-steel interface. Some cargoes diffuse slowly through the lining; once they reach the steel wall, electrochemical corrosion proceeds. The drum exterior may show no signs until catastrophic failure (pin-hole leak through the steel).
The mitigation: pre-shipment internal inspection (visual or by light-test) to confirm lining integrity, conservative cargo-temperature limits matched to the lining specification, and rejection of any drum showing surface defects on receiving inspection.
Container loading for lined drums
Lined drum loading is identical to standard steel drums:
| Container | Drums (200 kg fill) | Drums (220 kg fill) | Cargo mass |
|---|---|---|---|
| 20-foot ISO | 80 | 80 | 16-17.6 MT |
| 40-foot ISO | 160-180 | 160-180 | 32-36 MT (exceeds weight limit; load capped at ~140 drums) |
| 40-foot HC | 180-200 (single tier) | 180-200 | 36-44 MT (weight-out before volume) |
Heavy-cargo lined drums (concentrated acids at SG 1.8-1.9) load at 80 drums per 20-foot container with the cargo at 200 kg net per drum and the drum tare at 25-30 kg. Total container payload approaches 21-22 MT, near the weight limit.
UN certification for lined drums
A lined drum that ships DG cargo carries the same UN marking as an unlined 1A1 steel drum. The UN test regime certifies the drum-as-a-package, not the lining specifically; the lining adds chemical compatibility but does not change the structural rating. Reconditioning a lined drum requires both the lining replacement (or recertification of the existing lining) and the drum-body recertification per IMDG schedule.
Cost economics for lined vs alternative formats
For a 16 MT shipment of concentrated nitric acid 65%:
| Format | Drums or units | Drum cost (USD) | Cargo handling | Total per-MT cost |
|---|---|---|---|---|
| Phenolic-lined steel drums (200 kg net) | 80 | USD 60 each | High (per-drum dispense) | ~USD 300 per MT (drums + handling, before freight) |
| HDPE drums (200 kg net) | 80 | USD 35 each | High | Cargo would attack HDPE within months, not viable |
| Composite IBC | 16 | USD 200 each | Medium | ~USD 200 per MT |
| ISO tank | 1 | n/a | Low (bulk dispense) | ~USD 50 per MT (per-trip lease) |
Lined drums make sense when buyer infrastructure cannot handle IBC or ISO tank discharge, or when downstream usage requires drum-by-drum traceability. For volume buyers with bulk infrastructure, IBCs or ISO tanks dominate the per-MT economics.
Operator note: pre-shipment lining inspection
Before any lined drum is filled, a pre-shipment internal inspection should confirm:
- No visible cracking, peeling, or chalking of the lining
- No localised colour change indicating prior cargo penetration
- Bung threads clean and free of lining debris
- Drum-body exterior free of dents that may have cracked the interior lining
A 5 percent reject rate on incoming lined drums at a typical Chinese chemical factory is realistic. Pricing the cost of rejected drums into the order helps avoid disputes.
Related terms
Drum is the parent reference covering all UN-coded drum types. HDPE drum is the alternative for HDPE-compatible cargoes. Fibre drum is the paperboard alternative for solids. IBC is the next size up. IMDG Class 3 flammable liquids, Class 8 corrosives, and Class 5.1 oxidisers commonly ship in lined drums.