Snapped steel tracks on a rare machine: getting an Extec C-12 crusher back in service

When both steel chains failed on a tracked jaw crusher with a limited parts market, the margin for error on a replacement order was close to zero.

The Extec C-12 is not a machine you see every day. Built in Swadlincote, Derbyshire by Extec Screens & Crushers a company founded in 1987 that grew to become one of Britain’s leading mobile crushing and screening manufacturers before being acquired by Sandvik in 2007 the C-12 was the flagship of the Extec range: a full size, track mounted primary jaw crusher designed for hard and demanding applications in quarrying, demolition, and recycling.

When a customer’s C-12 came to a standstill with both steel track chains snapped, the clock started ticking. Machines like this earn their keep by running, not sitting. And a crusher with snapped chains is exactly as useful as the pile of stone it was supposed to be processing.

The parts problem

The C-12’s undercarriage presents a sourcing challenge that buyers of more common excavators rarely encounter. The track chains on this machine run to 54 links and are configured to accept either 15-inch or 20-inch wide steel shoes a spec that matches only a handful of machines in the wider equipment world. That narrow compatibility pool means there is no deep aftermarket, no shelf stock at the average dealer, and no quick domestic fix.

In this case, the customer’s steel shoes were still in serviceable condition. The real unknown and the real risk was whether a replacement chain from an alternative supplier would align with the existing bolt hole spacing on those shoes. Get it wrong, and a set of expensive replacement chains becomes scrap metal or has to be shipped back at the customer’s cost.

THE FREIGHT MATH

One way shipping on a set of track chains for a machine of this size runs around $750. An incorrect fitment means a return shipment on top of that a minimum $1,000 loss before a replacement set is even reordered. Getting the measurement right the first time is not optional.

How the order was handled

Before anything was committed to a purchase order, every relevant dimension was documented and cross checked. Bolt hole centers, chain pitch, shoe width, and link count were all verified against the customer’s existing hardware. Only when the measurements confirmed a 99% confidence of fitment did the order go ahead.

The chains arrived, the shoes bolted straight back on, and the C-12 was back in production within two weeks of the initial callout a turnaround that, given the scarcity of the parts, is genuinely quick.

CHAIN LINKS : 54

SHOE OPTIONS : 15″ / 20″ wide

Background: the Extec C-12

Extec built its reputation through innovative design and a willingness to push mobile crushing beyond what was previously considered practical in the field. The C-12 and its successor, the C-12+ with its updated CAT C-9 engine and redesigned compact chassis brought full size jaw crushing capacity to track mounted, self-propelled platforms capable of processing granite, limestone, concrete, asphalt, and demolition debris.

The machine’s 1,200 mm × 750 mm jaw opening and approximately 48-tonne operating weight put it firmly in the heavy end of mobile crushing. Extec’s export success during this period was recognized with a Queen’s Award for Export in 2005, a distinction the company repeated two years later. When Sandvik acquired Extec in 2007 for roughly $270 million, the C-12 was already a well established machine with a global installed base which is exactly why worn and aging examples continue to turn up in yards and quarries today, still working, and still occasionally in need of parts that take some effort to find.