When you think of vehicle production, you think of long lines of overhead conveyors moving large body parts and heavy engines in automated synchronisation, all at the higher-capacity end of the scale. That is certainly part of it and some requirements are for very high-capacity lifting – and can be very specialised. Die presses, for example, for stamping out body parts – doors, side-panels, and the like – are heavy; a weight of tens of tonnes is typical.
And these days flexibility is a requirement of automaking: shorter model-runs, with frequent variations, are the norm, and a change or upgrade of model may require a change of die in the press. Dies also need to be turned – in the horizontal plane – for installation and sometimes flipped – in the vertical plane – for maintenance.
So die-changing cranes are an essential – indeed a core – process in an auto assembly plant, and specialised – and highly automated – cranes for the purpose are in demand.
Konecranes has been supplying the such cranes to the automotive industry for over 40 years. Their die handling cranes are typically double-girder bridge cranes that can be equipped with various trolley configurations. A common trolley carrying two winches is a frequent arrangement; others are two individual trolleys, motorised rotating load hooks, and manually adjustable load crossbeams.
During a load turning operation, diagonal pull between the two hoists is unavoidable. For this application, Konecranes allows the load to be turned only in a closed system: as the hoists are pulled towards each other, the stresses are entirely taken by the body of the crane and no forces are introduced into the building structure.
Safe die turning and flipping needs other special measures and sensors. One such is bidirectional overload sensing. Normal overload sensing may be inadequate here. The reason is this: to flip a die, the main hoist and auxiliary hoist lift it horizontally in tandem. The auxiliary hoist then lengthens its rope, allowing the die first to tilt, then to hang vertically from the main hoist. The die is rotated around the vertical axis; the auxiliary hoist takes up its slack (attached now to the bottom end of the free-hanging die) and again raises the die to the horizontal.
The end result is that the die is once again in a tandem lift, but this time inverted, with its previously upper surface now pointing down.
If the total weight of the load is greater than the load capacity of the auxiliary hoist, it is not permitted to lower the main hoist at any point during the entire turning process – because the change of angles and CoG position might increase the load on the auxiliary hoist beyond the permissible. Lowering the die when it is in an inclined position is only allowed with the auxiliary, smaller, lifting gear. Should one hoist be overloaded, the other hoist is blocked in its lowering movement and only lifting at creep speed is possible. This prevents the overloaded hoist from being overloaded even more by lowering the load with the non-overloaded hoist.
Similarly, in turning diagonal rope pulls are inevitable. Diagonal pull monitoring is, therefore, a requirement. The maximum permissible rope angle is measured during the entire turning process. Rope angles of up to ten degrees are permissible. If that is exceeded, an emergency stop is generated, and a fault message is displayed.
An alternative to the above is the die gripper crane with, as the name suggests, a below-the-hook gripper mechanism, in which slewing gear is integrated. It gives a stable 4-point suspension with a balancing rocker that can tolerate a centre of gravity eccentricity of 100mm, dependent on the maximum die weight. It can give millimetre-precise pendulum-free positioning, and because of the compensating rocker, the strain on all four suspension ropes is equal. Synchronised sensors, with redundancy built-in, connect to fail-safe programmable logic controller.
Fully automatic
There may be dozens, perhaps hundreds, of such dies in an auto plant, with dies sets needing to be changed frequently since press-cycles can be short. The automatic die gripper cranes can be used, in automatic, semiautomatic or manual mode, to keep track of them as part of the Konecranes Warehouse Management System (WMS). Together they enable fast, compact, and multilevel storage of the pressing dies.
RFID information is stored on each die along with its weight, the gripper width required, and sequence of transport orders that will send it to its destination for a die exchange, as well as its storage position within the warehouse. In semi-automatic mode, the WMS visualises the destination and sends the die there with a minimum of operator interventions, considerably streamlining the operation and reducing the risk of errors.
BANG Kransysteme, based in Saxony, have provided several fully automatic automotive die transport cranes for various press shop layouts. “Before 2000, the automotive sector had a relatively small model range and produced individual pressed parts in very large quantities,” says Peter Knösel, their head of sales.
“Simply attaching die tools with slings was sufficient, and the number of tool changes was very low. From 2000 onwards, the increasing model range necessitated faster setup times, leading to the development of die grippers. Set-up times came down to 1.5–2 hours.”
The Porsche Smart Press Shopp in Halle, which BANG Kransysteme equipped, is considered the most modern press shop in the world. “The focus is on the production of exterior body panels in aluminium or steel, as well as the manufacturing of small batch sizes,” he says.
Two die gripper cranes running in full-automatic tandem mode bring the total cycle time under 25 minutes for a 6-table-tandem press. One crane in fully automatic mode usually takes under 50 minutes to change six dies. The pick-up and set-down positions of the tool gripper are reached with an accuracy of +/-10mm.
BANG Kransysteme’s crane management software, called CranoMatic, was developed in-house for seamless integration into process cranes control systems with stamping die storage particularly in mind. It gives up to 60% faster die set exchange compared to manual.
It manages transport orders, optimises operating times and provides real-time information on operating and system status. Safety benefits also follow. No Fly Zones (Forbidden Areas), where the crane is not allowed to move; Travel Zones, where it moves via designated way points and adjusts its path to travel around obstacles; and Efficiency Sync, which manages all crane axes to adjust their movements so that they reach the target simultaneously – the slowest axis determines the travel time, while all others move at reduced speed in sync.
“The efficiency of these production areas in the automotive industry is directly dependent on the crane handling capacity and the precise work of the engineered tool gripper,” says Knösel. “The main role of the operator is to initiate and supervise the operations.”
The standard
Street Crane has been supplying overhead cranes to the automotive industry globally. Caterpillar, Mercedes-Benz, Toyota and Volvo been some of their many clients. They too deliver press plant cranes for the efficient storage and retrieval of heavy dies used in vehicle body panel production. Cranes feature ZX electric wire rope hoists with capacities up to 60t; precise turning operations and automated product placement controls again are key. Automation and semi-automation technologies are standard here.
Among their products for the automotive sector are twin hoists with load summation. Twin hoists are designed to work in tandem, ensuring balanced lifting and precise load handling. The load summation feature allows for the combined weight of the load to be accurately measured and distributed between the hoists, enhancing safety and efficiency. Secondary braking and load arrestors provide an additional layer of safety, as does overspeed protection, which also helps prevent mechanical failures. Micro-speeds and infinitely variable speeds give precise control over the lifting speed, allowing for smooth and accurate positioning of loads. Micro-speeds enable very slow movements for delicate operations, while infinitely variable speeds allow for different lifting requirements. There is also a Load Dependent Speed feature, which adjusts the speed of the hoist based on the weight of the load being lifted. This enhances efficiency and reduces wear and tear on the equipment.
Crane monitoring is an integral part of the package. Design Working Period (DWP) Monitors track the usage and operational life of the crane; condition monitoring systems continuously assess health and performance of the equipment. By detecting potential issues early these systems help in preventing unexpected breakdowns and ensuring smooth and safe operations. Controls comply with stringent safety standards ensuring high reliability and performance designed to handle high-risk applications with a high degree of fault tolerance.
Dennis Eagle are the UK’s leading manufacturer of refuse collection vehicles and have been setting the standard in waste and recycling solutions for over a century. They turned to Granada Cranes – a longstanding partner – to replace an ageing crane at their facility. Their goal was to modernise lifting operations with a more efficient, reliable, and compliant solution while keeping downtime to a minimum. The project needed to deliver a safe working load of 6,000kg to handle large components in vehicle assembly, and to give enhanced operator control and smoother load movement. Dennis Eagle needed a long-term solution to the latest safety standards.
The new crane from Granada is a single box beam girder design, of 22m span, fitted with an ND04L6DEP electric wire rope hoist from SWF delivering 5.5m lift height. Hoist speeds are 5 metres/minute at fast speed, 0.8 metres/minute slow; travel speeds are inverter controlled, at 20m/min and 5m/min cross travel and 40m/ min and 10m/min long travel. The crane classification is ISO M5-M6 (intense- super duty). Control is by mobile pendant, mounted to the crane and moveable along the bridge.
The crane has made a significant difference to Dennis Eagle’s operations. By replacing the outdated system with a modern, inverter-controlled crane, their operation has gained smoother load handling, reduced wear on key components, and improved operator safety.
Delicate balance
But not everything automotive is on this scale. Engine assembly, for example, is delicate work. Components are small; precision is essential; operators need manipulation on a fine scale. Yaplex have been working with the automotive industry for over a decade and have more than two hundred systems operating within this sector.
Their zero gravity electric balancers, for example, have found wide-spread adoption. An electronic controlled servo-drive and motor performs the lift. An ultra-sensitive handle gives the operator compete control. When used in so-called ‘float mode’ it automatically senses the weight of the component and adjusts the balance accordingly. The operator can control and manipulate it intuitively, and without muscular strain no matter what it weighs; it is, therefore, a highly ergonomic system as well.
It can be integrated into the end effector or end tooling, and has configurable inputs and outputs to integrate with other production equipment. Built-in parameters and patented safety devices make the system failsafe.
In one facility, the zero gravity balancer with a bespoke gripper is used to assist operators assemble high powered petrol engines, lifting crankshafts from an inspection bench into the cylinder block. In another, for handling engine blocks on a production line, the system is mated with a mechanical clamp to securely grip and auto latch/de-latch the load. Fingertip throttle controls gives fast and accurate handling. In yet a third example, the zero gravity balancer with a bespoke gripper is mounted on a lightweight tracking system to assist operators to lift cylinder heads through the machining process. The system is designed to weightlessly lift the completed heads from the conveyor and into packaging with optimum speed and safety.
Multiple standard capacities are available, from 50kg to 600kg SWL. Their solution, say Yaplex, is the fastest lifting device on the market. It offers speeds up to 2m/s per second when required.
For high capacity lifting as well as for small loads, the automotive industry requires reliability allied with accuracy and speed. The transition from internal combustion to electric vehicles will only increase the demand for new overhead lifting in the sector. We may confidently, therefore, expect it to expand.
Granada lifts for powertrain investment
Granada Cranes recently completed the design, manufacture and installation of a 34t + 34t double girder overhead travelling crane and gantry system for an auto industry client. Evertec/JVM is a tier one supplier to the global automotive industry, delivering components and assemblies across all powertrain types, from internal combustion engines to hybrid and fully electric vehicles.
This summer, as part of its £40m investment to boost the UK’s automotive supply chain, the company had a £14m Colosio DM3000 high-pressure die-casting machine installed at its plant in Worcester.
It will produce high-quality aluminium castings and is the first of its kind in the UK. The new crane is to handle high capacity lifting demands in line with the new machinery.
It has two 34t SWF hoists; the crane was engineered with load summation technology that allows either or both hoists to be used without exceeding a combined maximum load of 34t. This critical safety feature ensures compliance and operational safety when lifting heavy or irregularly shaped items, particularly during rotational handling or load turning. The Cattron radio control system was customised with three joysticks – one for crane travel and one for each hoist – giving the operator full independent control. This setup supports precise manoeuvring, especially useful when turning or aligning components during assembly or installation processes.
A full-length catwalk/service platform with gate access and interlock safety switches supports maintenance and inspection; the system is powered by Colton Downshop Conductor Systems, exclusive to Granada Cranes, claimed to be the oldest and the safest finger-proof conductor system. The system was installed with performance and longevity in mind, reducing the risk of downtime and simplifying future servicing.
