Simple change to promote safety and improve cargo-handling efficiency

With the support of Transnet Port Terminals (TPT), a local manufacturer has designed a trailer that will make it safer and easier to move containers from ship to shore. The mammoth delivery of a multimillion rand consignment of 66 new ‘cornerless bathtub’ trailers designed and manufactured by Pretoria-based Afrit, has brought to a close months of intensive market research, supplier scouting and short-listing in a collaborative effort between representatives of TPT’s procurement and technical teams.

The trailers will not only streamline operations and speed up container turnaround times, but also provide a far safer method of moving containers from ship to shore. Sixty trailers have been delivered to Cape Town container terminal as part of the facility’s R4.2 billion capacity creation project while six were delivered to Pier 1 container terminal in Durban.

Intensive research

Ernest Bell, Commercial Specialist in TPT’s Procurement Department, said that TPT senior management had made a strategic decision to approach local OEM’s (original equipment manufacturers) of trailers directly and not accept proposals from any third parties.
“The size of this order meant that it was critical for us to work with the actual manufacturer, rather than a third party who outsourced to the manufacturer, added a mark-up but then was unable to provide adequate after-sales service and maintenance to meet our stringent requirements,” he said.

Instead of relying solely on tender submissions, Bell said the process had required a nationwide search and visits by TPT to dozens of trailer manufacturers across the country. These were whittled down to a selection of suppliers boasting a national footprint, in-house capacity to cater for TPT’s requirements and a proven track record of excellent service, quality and back-up assistance.

Afrit was one of the short-listed companies. Bell said the company eventually scooped the contract due to its competitive pricing and a significantly shorter delivery time frame of just four months, backed by a sound track record.

Design changes
While essentially serving the same purpose, the new Afrit trailers offer a simple yet effective change: they do not have the closed corners of traditional trailers. This made it difficult to load containers directly onto trailer vehicles and access the corner cone fasteners.

Harry Dickinson, Project Manager at TPT, explains: “Containers stacked on a vessel have twist lock cones at each corner to secure them while in stack. In the past this meant we could not load the container directly from a vessel onto the old trailers until the twist lock cones were physically removed from the container. The container would have to stay suspended at least two metres in the air for a long period of time so the cones could be physically removed.”

This process also posed safety risks: the suspended container or the loosened cones could have fallen and caused serious damage or injury to those working around it.

With the Afrit-designed bathtub trailers, the sides are raised and curved inwards to enable the crane operator to lower the container on to the trailer, where it will locate itself without the operator having to conduct a series of manoeuvres. This saves time in the loading procedure. The new rounded design is already in use at major European ports.

The trailers are of heavy duty construction with a capacity of 65 tons to carry two six metre containers with a combined weight of 60 tons or one fully laden 12 metre container. The axles are supplied by Henred and are 40 ton walking beam design with heavy duty leaf springs.
Adding to the high impact capabilities of the trailer, the axles are fitted with solid puncture tyres which have minimal deflection under impact loading. Also the fitting of these tyres has given Transnet a large cost saving in providing a low instance of tyre replacement and puncture repairs. Maintenance on these trailers has been cut down to a minimum by fitting the Groeneveld self lubricating system. A departure from the norm in trailer manufacturing was included in the design in the landing legs.  The truck tractors used to transport the trailers are of special design and are fitted with hydraulically adjustable 5th wheels which lift the trailers before locking them in place.
 
Said Dickinson, “Equipment like this would usually have to be imported from the country that had perfected this unique design. Working with a local supplier throughout this process meant that the end result was beyond all expectations.”

 “TPT and Afrit were in constant communication throughout the process. Afrit had initially provided us with a prototype which we tested in operations. This allowed us to make working changes and tweak the design to finally fit the specific needs of our terminals,” said Dickinson.

He said the bathtub trailers were an example of design and manufacture that not only meets the standards of its European counterparts but also caters specifically for South African needs. 

(Source: Transport Weekly)