Liquefied Gas Transport Semi-Trailer

What this tanker is

An LPG road tanker semi-trailer, manufactured in our own factory. It is a pressure vessel: the gas is held as a liquid at ambient temperature by the pressure inside the shell rather than by refrigeration.

The shell is Q420DR, a low-temperature pressure-vessel steel. Design pressure is 1.76 MPa, with minus 0.04 MPa on the vacuum side, over a design temperature range of minus 40 to plus 50 degrees Celsius. Gross weight is 40,000 kg and payload is 25,502 kg. Overall it is 13.40 by 2.55 by 4.00 m. The saddle sits at 1,240 mm with a saddle load of 1,600 kg, and the whole trailer is designed to run behind a 6×4 tractor unit.

What it is used for

Fuel distribution and haulage. Moving bulk LPG from a coastal import terminal or a refinery to inland filling plants, bottling depots and industrial users. Supplying autogas stations. Feeding cement works, glass plants, food processors and any industrial burner that has moved off diesel.

Across West and Central Africa the LPG trade is expanding with domestic cooking gas programmes, and the trailer that moves the product inland from the terminal is the constraint in most of those supply chains.

Why the numbers on this page matter more than usual

On most trailers the specification is a guide. On a pressure vessel it is the product, and three figures decide whether it is the right one.

Design pressure, 1.76 MPa. This is what the shell is engineered to hold and it is what your regulator will read first. It is not a marketing number and it is not adjustable after the fact.

Design temperature, minus 40 to plus 50. The lower end is about the steel rather than about your climate: Q420DR is specified for low-temperature service so the shell does not become brittle under the conditions a liquefied gas creates inside it. The upper end is about yours.

Payload, 25,502 kg at 40,000 kg gross. Note that the useful load is about 64% of the gross. A pressure vessel is heavy because it has to be, and any trailer offering you a dramatically better ratio is worth asking hard questions about.

The saddle height of 1,240 mm is the fourth number, and it is the one most often overlooked. Check it against the fifth wheel on the prime mover you intend to use.

Condition and what we do before it ships

New build, out of our own workshop. The shell specification is what the Proforma Invoice describes and it is agreed in writing before any deposit.

The same honest point applies here as to our cryogenic trailer: pressure vessels are regulated by the country importing them, and the inspection regime, the plate markings, the valve arrangement and the periodic testing all vary. Send us your authority’s requirement and we will tell you plainly what we can build to. What we will not do is assure you a tank clears a rule neither of us has read.

Shipping it, and what the volume means

At 13.40 by 2.55 by 4.00 m this is one of the largest single items in our catalogue by the box it occupies on a vessel, and sea freight is charged on that box rather than on the tare weight. It is worth quoting the freight before you commit to a quantity, because two of these is a meaningful shipment on its own.

Loaded at our yard in Tangshan, shipped through Tianjin Port.

What to tell us

Your product, your volumes and your terminal’s loading arrangement. What your national authority requires on pressure-vessel certification. The prime mover you will use, or whether you need one from us. Your destination port and the quantity.