Ranging in capacity from 5-25t safe working load (SWL) the ZX6-8 Series hoists are designed for high volume production, but with the adaptability to meet individual customer and local market needs. The new hoists have 30% fewer components than their predecessors and production time of a typical standard unit will go from 40 to just 9.5 hours.
Street says it has been operating at top capacity for two years, but plans to increase production of the new units by three times.
In the UK, the new ZX range will be offered on whole cranes engineered by the company. Elsewhere in the world, the company will supply hoists via distributors, most of whom use the Street software package to quote, design and build cranes from Street Crane kits. Street is constantly striving to expand this dealer network.
Andrew Pimblett, managing director, says: “In a world where end users can receive multiple offers for the same hoists made by the one or two multi-national companies selling under multiple brands, customers want a real choice. Working together with independent crane makers around the world, Street is setting out its stall to offer this choice,” he adds.
Nanjing Hoisting Machinery General Works Company Limited (NHM), will also start-up manufacture of ZX6-8 hoists for the Chinese home market
The company has local stocking arrangements with its master distributors and it anticipates establishing regional configuration centres to hold hoists in knock down form for local assembly. The flexibility of the design should make the localisation of the hoists for particular markets straightforward. Pimblett says: “The reason we appeal to crane makers is that we offer a package where we give them the exclusive control of a region and we won’t compete for the end user crane business or parts and service. This exclusivity adds value to their business.”
Following the start of production at Street’s Derbyshire factory, trade partners Nanjing Hoisting Machinery General Works Company Limited (NHM), will also start-up manufacture of ZX6-8 hoists for the Chinese home market. In an agreement signed last year, NMH will manufacture under licence the complete range of Street ZX hoist units solely for the Chinese market, whereas Street will manufacture in the UK for all other world markets.
Pimblett explains that there are two markets in China. First, he says, there is a top end market, where the likes of Konecranes and Demag (and previously Street to some extent) supply top-end European hoists to the “higher level” market. Secondly, adds Pimblett, there is the traditional market, supplied by around eight manufacturers who manufacture more dated models for low prices. “These were initially licensed when the companies were state owned,” he adds.
Street believes it can capture the “middle ground” between the two markets and supply quality western hoists at affordable prices. Not as cheap as what Pimblett calls the “traditional” market can offer but, at the same time, not as expensive as what other manufacturers will charge.
Ranging in capacity from 5-25t safe working load (SWL) the ZX6-8 Series hoists are designed for high volume production, but with the adaptability to meet individual customer and local market needs
Such is the diversity of the range, Street says, other markets, which require unique specifications (Australia and Canada, for example) can also be catered for.
Service
Outside the UK, Street’s distributors will provide after-sale service on the ZX range.
It claims that other companies strategically design and install their hoists and cranes with electronics and solid state controls that can only be serviced and maintained by their own technicians. Street has gone in the opposite direction.
“Some end users, say, in Australian mines,” says Pimblett, “get their own electricians or service engineers to maintain lifting equipment. They could not do this with many of our competitors’ units and are certainly not prepared to entertain flying in specialist engineers.”
The company has local stocking arrangements with its master distributors and it anticipates establishing regional configuration centres to hold hoists in knock down form for local assembly
The information technology and electrical components, for example, require a skill-set almost exclusive to the manufacturer that designed it, Pimblett suggests. “How can dealers operate independently if they need the manufacturer to carry out the service?” he asks.
Konecranes CEO Pekka Lundmark makes no secret of this, having targeted 10% organic and 5% acquisitional growth in the service sector.
At the outset of the ZX journey, Street looked at Konecranes, Demag, Stahl, and Abus units, for example, to build the framework for a range that could be competitive on price but also offer “fundamental advantages,” as Pimblett puts it, to the distributor network and, in turn, the end user.
‘It’s not just a new bit of kit,’ says Chris Russell, chief design engineer, who was largely responsible for the development of the firm’s next generation
“It’s not just a new bit of kit,” says Chris Russell, chief design engineer, who was largely responsible for the development of the firm’s next generation.
True enough, the whole specification and ordering process, from the end user, to the dealer, to Street and back again, is supported by an astonishing, state-of-the-art three dimensional virtual world. Hoists, cranes and their components exist in a virtual form, 24 hours a day.
This also serves as training documentation for distributors, and yet from a maintenance point of view, units are not complex.
Hoist was granted exclusive access to its headquarters as the final touches were being made to its new production line
Russell says: “The whole thing has been designed with serviceability in mind.”
Key to the design process was the use of 3D modelling, allowing the product to be created in virtual reality, enabling the interaction of components to be explored and designs optimised to take account of all possible component selections.
As the hoists were refined and component designs and sources agreed, an integrated design management system was used to document all component changes. These updates were automatically notified to supply partners so that everyone was aware of the latest design modification. Changes could include not just the configuration of the part, but material, alternative materials or components, manufacturing technique, quality measurements, certification to national standards, and traceability information.
When Russell, for example, updates or changes a single component within this 3D world, it triggers emails to every relevant member of staff at dealer companies and the virtual hoist is recreated accordingly.
Gearbox
One of the most critical components on any hoist is the gearbox. The ZX6-8 gearboxes use hardened precision ground gears immersed in oil within a machined gearbox case. This mechanism handles the full reduction, a safer and more reliable alternative than the common practice of using an overhung pinion driving an open spur ring inside the hoist drum.
Pimblett says: “With this, as with every element, we are not prepared to compromise the quality and performance of the hoist. For every technical challenge we have used the best possible engineering solution.”
An intensive programme of accelerated life tests has been applied to the hoists, allowing the effect of many years operation to be compressed into a few weeks 24/7 operation. With full loads, lift and fall cycles were followed with speed changes and pauses so that mechanisms were severely challenged. Advanced vibration analysis was also undertaken to allow the performance of each individual component to be isolated and performance optimised.
Street has adopted a universal design for the hoist chassis that allows many of the structural components to be standardised. Cellular construction permits high speed assembly and allows for ease of localisation for different markets and customisation to meet end user needs. A responsive and lean supply chain has been established to permit on-time manufacture without reliance on high stock levels of components or excessive work in progress.
Quality
The ZX6 and ZX8 hoist units will be built in an environment where nothing is more important than quality. Every aspect of the hoist assembly is covered by a written procedure and every worker in the line is trained and signed off in the procedures. Hoists are tested at various points along the line and every hoist undergoes a two-hour end-of-line test and inspection procedure in which the function of every component is tested.
ZX10
Street’s ZX10 hoist model, with capacities up to 50t, will be launched later in the year.
Six key features of the ZX range:
– Trolley reaction roller, avoids the need for a counterweight, increases the life of the rolling surface, reduces shipping and transport costs.
– “SC Smartdrive” technology ensures smooth acceleration and controlled stopping with minimised load swing, sensorless current vector method of motor control out-performs the voltage frequency method, incorporates a plug-in control terminal board with memory providing simple change over if re-programming is required – CE, UL, cUL and TUV approved.
– Heavy duty rope guide ensures positive rope scrolling, designed to prevent “slack rope” conditions, specially selected self-lubricating material.
– Direct drive trolley with flangeless traverse wheels and side rollers for high durability and reduced wear, sealed for life maintenance free bearings in hoist the trolley frame.
– Superior load safety, low maintenance long-life hoist brake, acts on the gearbox shaft not motor shaft, mounted externally for improved ventilation and cooling, asbestos free brake linings, automatic braking in the event of power failure.
– IP55 steel electrical control cubicle, quick release plug and socket connections, hours in service metre, phase failure relay protects the hoist against incorrect phase sequence, phases failure and connection to over or under voltage, mechanical over-speed switch for improved operator safety, fully ferruled and identified wiring.
