20ft Customized Offshore Reefer Container | DNV 2.7-1 | LongTeng Industrial

Created on 09.24

What This Unit Is

A 20ft offshore reefer container is a refrigerated container built as offshore equipment. Inside: an insulated envelope, a refrigeration machine and a working range down to about −25 °C. Outside: a steel lifting frame, forged pad eyes, a certified four-point sling set, and a data plate that traces back to the certification file.

It is not a marine reefer dropped into an offshore frame. A marine reefer is a panel structure carried as cargo; an offshore container is a lifting appliance designed around a dynamic load case. Bringing the two together is a design job, not an assembly job — which is why every unit we build for this application is engineer-to-order.

Two Structures, One Unit

The design conflict sits in the middle of this product and decides almost everything else about it.

A reefer wants a continuous insulated envelope.

An offshore container wants a lifting frame.

The two cannot share a load path.

So on a properly built offshore reefer the frame does the lifting and the envelope does the insulating. Where the two meet — pad eye position, machinery mounting, steel-to-aluminium isolation — is where the design hours go. There is no standard 20ft dry box to start from, and we do not pretend otherwise.

How We Build It

The frame. Fabricated from structural steel, with the pad eyes landing on primary members — never through the panel. Corner castings located to ISO 1161 geometry on a jig, so the lifting and stacking interfaces stay inside tolerance.

The lifting set. A four-point sling set matched to the unit, proof load tested, and certified separately from the container, with the sling length and angle range stated on the certificate.

The insulated envelope. PU foam sandwich, 100–150 mm in walls, floor and ceiling, with stainless steel, aluminium or GRP lining. Built and assembled inside the frame, so the envelope is carried rather than loaded.

The machinery mounting. A refrigeration unit is the heaviest concentrated mass on the box, and it sits where the frame is most challenged. We size its mounting frame for the offshore acceleration case, not for road and sea freight.

The steel-to-aluminium interface. Wherever aluminium and stainless meet steel we isolate the joint. Left bare, salt spray and condensation make a small battery cell, and the aluminium loses. Isolating washers and stainless fixings cost very little, and they are the first thing a cheap build drops.

The coating. C5-M system, 280 μm nominal DFT over steel shot-blasted to Sa 2.5, with a heavier build for splash-zone or tropical service.

How an Engineer-to-Order Unit Runs

Every offshore reefer leaves this works against a drawing agreed before fabrication:

Technical review

Drawing and calculation package

Approval and material release

Fabrication

Testing and certification

Pre-delivery inspection

We do not cut steel before step 3 is signed off. After that point a change is a revised drawing, not a decision taken on the shop floor.

What Ships With the Unit

DNV 2.7-1 / EN 12079-1 / ISO 10855 certification

Proof load test record

NDT reports

Data plate

ISO 1496-2

Temperature performance record

Third-party inspection is welcome at any stage — SGS, BV, LR, DNV, ABS, or your own nominated inspector.

Where It Is Built

LongTeng Industrial manufactures from a 50,000 m² facility with two production lines, engineering and fabrication under one roof. Welding is carried out in-house to a recognised welding standard. That combination is what makes engineer-to-order practical here, rather than a negotiation with a subcontractor.

Direct factory pricing

The drawing is ours

Lead time

Repeatability

Specifications

Parameter	Value
External length	6,058 mm
External width	2,438 mm
External height	2,591 mm (high cube available)
Internal volume	≈ 26 m³ (insulated construction)
Tare weight	≈ 3,800 – 4,500 kg, depending on fit-out
Maximum gross weight	30,480 kg
Working temperature range	−25 °C to +25 °C (−30 °C on request)
Temperature control	Set point held to ±0.5 °C, recorded
Insulation	PU foam sandwich, 100 – 150 mm walls / floor / ceiling
Lining	Stainless steel, aluminium or GRP
Floor	Aluminium T-section or stainless, with drainage
Refrigeration machinery	Thermo King, Carrier or equivalent
Lifting structure	Lifting frame with pad eyes on primary members
Lifting set	4-point certified sling set, proof load tested, separately certified
Coating	C5-M system, 280 μm nominal DFT
Certification	DNV 2.7-1 / EN 12079-1 / ISO 10855 plus ISO 1496-2
Power	380 – 460 V, 3-phase, 50 / 60 Hz to specification
Documentation	Data plate, weld map, NDT, proof load and temperature records

Build Options

Set point and range

Door arrangement

Internal fit-out

Insulation and lining

Refrigeration

Instrumentation

Lifting set

Coating

Marking

Where These Units Go

Temperature-sensitive chemicals and additives held on deck

Provisions and food stores for platforms and vessels

Laboratory samples and medical supplies moving to and from installations

Deck cargo where the specification says "keep it cold, lift it by crane"

LongTeng Group is a private owned enterprise group involves in designing, manufacturing, trading and transporting of ISO dry cargo container, special container and house container, reefer container, tank container. Also provide container spare parts for repairing and manufacturing new container. The group have exported to over 60 countries. The total annual production capacity is 120,000 TEU of ISO Containers.