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									Steel wrist    19/11/09        3:10 pm       Page 1


     digging                                                                                    Graham Black reports on the latest tilt-
                                                                                                rotator hitch manufacturer to enter the
                                                                                                UK market, a concept that has already
                                                                                                proved its worth in railway maintenance
                                                                                                applications and is increasingly being
               wedish-based tilting and rotating hitch manufacturer Steelwrist has set up
               a UK sales and support arm, headed by Pat Bulcock. Steelwrist morphed            specified by knowledgeable muck-shifting
               from the Denteo company that in 1986 was producing bucket teeth, then
      progressed into quick couplers. It is one of the Scandinavian companies that              owner-operators.
      pioneered the development of tilting and rotating hitches for excavators. In
      2005 the company was re-branded by new owners and today its hitches are               offering and products from the UK market leader Engcon is the split of weight
      manufactured in a modern factory near Stockholm.                                      classifications of the various models. To illustrate this point, the demonstration
            Its range of tilting and rotating hitch attachments looks a fine                system was set up on owner-operator Calvin Fuller's new 16-tonne Volvo EC160C
      bit of Scandinavian design and engineering; the top half is a                         tracked excavator. It was fitted with a Steelwrist X18 unit weighing 390kg, which
      heavy-duty fabrication, the bottom half is cast steel. Hitch                              is designed to fit 12- to 18-tonne excavators.
      rotation is achieved by a conventional hydraulically-                                              On paper, the Engcon options are either the 340kg EC15 model,
      driven crown wheel and pinion, with bucket tilt                                                    designed for 12- to 16-tonne machines, or the 440kg EC20 model
      controlled by external hydraulic rams. The Steelwrist                                                  designed for 16- to 22-tonne excavators. The height of both the
      tilt-rotators allow a 45-degree angle of tilt to                                                             Steelwrist X18 and the heavier Engcon EC20 tilt-rotators is
      either side, compared to the more usual 40                                                                      virtually the same, with the smaller EC15 model just 10mm
      degrees. They are of a modular construction,                                                                     shorter.
      allowing an integrated hydraulic grab to be                                                                             Of course such equations may well work in
      fitted at a later date.                                                                                                 Engcon's favour at other popular weight categories.
            Perhaps the greatest area of                                                                                       The great advance that Steelwrist has made to tilt-
      difference between the Steelwrist                                                                                          rotators in general is their new digital control
                                                                                                                                    system, called XControl. To appreciate the full
      Calvin Fuller's incredibly well-                                                                                                implications of this development, we must
      specified Volvo EC160C                                                                                                           review the other options.
      includes three-piece front-
      end equipment and a
      Steelwrist tilting and
      rotating hitch.

                                                                                                                                     JANUARY 2010 EARTHMOVERS                    1
Steel wrist     19/11/09       3:10 pm        Page 2

      Right: To get the most out of the system third-           It is possible to use a tilt-rotator on an excavator                                                                                                                     with joystick control of the track motors, leaving an       example, I speculate that XControl could be used as
      party joysticks are really required, with built-in   by plugging it into the hydraulic hammer circuit and                                                                                                                          uncluttered cab floor without any pedals or levers to       part of a lift height restriction system. Fair enough,
      sliding proportional controls.                       using a combination of pedals and additional control                                                                                                                          trip over.                                                  you'll still have to buy all the sensors and the like,
                                                           buttons glued to the joysticks. But you really have to                                                                                                                             As it is at the moment, XControl sits like a digital   but you've already got one of the more complex
      Far Right: The XControl user interface can be used   factor in a couple of days of a specialist fitter's time                                                                                                                      parasite within the host excavator's electro-               parts of the system installed; the interface to control
      to store up to four separate operator preferences    to wire it all up, and even then this set-up wouldn't                                                                                                                         hydraulic system, with the ability for the tilt-rotator's   the host excavator.
      and to adjust the operating parameters of the        really do justice to what is a significant investment.                                                                                                                        brain to provide a simple gateway to control many               For the vast majority of UK and Irish fleet
      hitch.                                                    Simple on-off functionality of the various                                                                                                                               other functions of the excavator. Steelwrist's              managers the thought of adding another 6 to 8% of
                                                           hydraulic controls of the tilt-rotator is not really                                                                                                                          development plans include an updated version that           the cost of the base 16-tonne excavator by
      Below and Bottom: Nordic pattern                     good enough to position the bucket accurately the                                                                                                                             will plug directly into the host excavator's CANBUS         specifying a tilting and rotating bucket hitch is off-
      buckets are ideally suited to tilting                first time for really fine work, or to stack a pallet of                                                                                                                      digital nervous system, to become an integral part          putting. However, for those operators who have
      and rotating hitches, which                          supplies. Sliding proportional controls on the                                                                                                                                of the machine's intelligence network.                      mastered the system, the general opinion is that they
      encourages an operating style                        joysticks allow the operator to get much more out of                                                                                                                               This development will open up a number of              do not want to go back to a simple hinge joint at the
      that carries the soil on the                                  the attachment, by infinitely varying the speed                                                               rotators, but the really interesting thing about       opportunities to upgrade the excavator at a reduced         bucket, as they have experienced the advantages –
      bucket, not in it.                                             of the rotate and tilt functions.                                                                            XControl is that, in theory, it can be programmed to   cost, which will make the initial financial investment      in everyday work – of a wrist action that can also tilt
                                                                         Excavator manufacturers are increasingly                                                                 manipulate a host of other electro-hydraulic           in a tilt-rotator much easier to swallow. For               and rotate the bucket or attachment.
                                                                         offering more sophisticated joysticks as                                                                 functions. For example, on a wheeled
                                                                            standard, or as an optional extra. Hard                                                               excavator XControl could be used to
                                                                             wiring the tilt-rotator's controls to the                                                            provide joystick steering, without the
                                                                             excavator's own joysticks provides a                                                                 manufacturer's expensive factory-
                                                                                much more professional set-up, but                                                                fitted option. I was told
                                                                                 is often limited by the number of                                                                that the latest trend among
                                                                                  spare buttons on each joystick.                                                                 Scandinavian operators is
                                                                                                                              In addition to the two proportional hitch rotate    to have tracked excavators
                                                                                                                         and bucket tilt functions, there are other services to
                                                                                                                         control, including the quick-hitch, the optional
                                                                                                                         hydraulic grab and the hydraulic lock on the tilt-
                                                                                                                         rotator itself. These are in addition to any of the
                                                                                                                         excavator's standard functions that may be
                                                                                                                         controlled from buttons on the joysticks.
                                                                                                                              Those operators experienced with tilt-rotators
                                                                                                                         tend to opt for specialised third-party joysticks
                                                                                                                         when they get their next excavator, with a multitude
                                                                                                                         of buttons and proportional controls built in. By this
                                                                                                                         stage the tilt-rotator's in-cab control box is usually
                                                                                                                         best placed to take charge of controlling
                                                                                                                         proportional values, not the excavator.
                                                                                                                              What Steelwrist has done with XControl is to
                                                                                                                         take this a stage further, with a new digital
                                                                                                                         electro-hydraulic control system. This is
                                                                                                                         connected to the tilt-rotator by a single cable
                                                                                                                         and the tilt-rotator itself is powered by a pair of
                                                                                                                         simple one-way hydraulic supply lines, one in and
                                                                                                                         one out of the attachment.
                                                                                                                              It is a plug-and-play electronic system that is
                                                                                                                         apparently easy to install. The example provided                                                                                                                                                               Fair enough, owner-
                                                                                                                         was that in-cab power                                                                                                                                                                                    operators may not be able
                                                                                                                         connections consisted of a                                                                                                                                                                             to charge a premium for this
                                                                                                                         single cable, with detailed                                                                                                                                                                          more skilful approach, but the
                                                                                                                         instructions of where to plug                                                                                                                                                                    increase in flexibility of man and
                                                                                                                         it into the machine's standard                                                                                                                                                                machine may increase the chances
                                                                                                                         fuse box. There was no slicing of the                                                                                                                                                     of the combination being the first on,
                                                                                                                         wiring loom in the hunt for a suitable                                                                                                                                               and the last off, a site. Perhaps the best
                                                                                                                         live wire to power the various                                                                                                                                               illustration of this is a wheeled excavator equipped
                                                                                                                         components.                                                                                                                                                                 with a tilt-rotator with a set of pallet forks, in
                                                                                                                              So far so good. XControl                                                                                                                                               addition to a range of buckets. Being able to
                                                                                                                         conforms to the SS10 standard                                                                                                                                               accurately pick and place pallets could possibly
                                                                                                                         for the proportional control of tilt-                                                                                                                                       save the cost of an additional telehandler and
                                                                                                                                                                                                                                                                                                     operator on site.
                                                                                                                                                                                                                                                                                                          Alternatively, a single machine could excavate a
                                                                                                                                                                                                                                                                                                     trench, collect the pallet of pipes from the yard and,
                                                                                                                                                                                                                                                                                                     by using an integrated hydraulic clamp, place the
                                                                                                                                                                                                                                                                                                     pipes accurately in the trench. It would be masterful
                                                                                                                                                                                                                                                                                                     at backfilling, and easily capable of producing a
                                                                                                                                                                                                                                                                                                     finished grade in most circumstances.

                                                                                                                                                                                                                                                                                                     The Steelwrist tilting and rotating hitch looks a
                                                                                                                                                                                                                                                                                                     robust bit of Swedish engineering. An integrated
                                                                                                                                                                                                                                                                                                     hydraulic grab can be easily added if required.

      2    EARTHMOVERS JANUARY 2010                                                                                                                                                                                                                                                                            JANUARY 2010 EARTHMOVERS                   3
Steel wrist     19/11/09        3:11 pm       Page 4

          Tilting and rotating hitches were originally         rectangular blocks or layers at a fixed angle and           set of fixed levers, then imagine the results if you
      developed in Scandinavia, partly to reduce the           orientation to the dipper arm. This produces a              used your hand to excavate the material.
      requirement for labourers. This was done for             pixillated landscape; a tilt-rotator allows an                  Calvin Fuller, the owner-operator helping out at
      environmental reasons – it gets very cold for            experienced operator to create a flowing 3D high-           the UK launch of Steelwrist, had an interesting
      someone working outside – and for economic               definition shape, without having to constantly              observation to make. He's an experienced tilt-
      reasons: the cost of local labour is high. These         reposition.                                                 rotator user and has a number of attachments,
      factors may not apply to UK and Irish job sites, but          But why bother? In an intensive loading or             including standard UK buckets, modified for use
      the end result matches a drive on our job sites          excavation application it is doubtful if a tilt-rotator     with the Scandinavian hitch pattern. It was the first
      towards having the minimum number of people in a         would provide any real benefit, indeed it would be a        time he had used a Nordic pattern bucket and he
      trench and close to an excavator's bucket.               hindrance. If I were a better operator, I could see         expressed his surprise at just how well it had
                                                               myself digging a very neat standard grave from a            complemented the tilt-rotator.
              First impressions                                single location, a task that the vast majority of
                                                               standard mini-excavators cannot perform.
                                                                                                                               The bucket has chamfered corners and a long
                                                                                                                           toe; the material tends to sit on the bucket rather
            I had a short while in the cab of a Volvo EC35C         But doing such specialist tasks would not              than in the back of it. In better conditions and with
      equipped with a Steelwrist X04 tilt-rotator in very      account for the popularity of such attachments in           more experience, I could well imagine having better
      sticky, wet clay. I'm no operator, but the first thing   Scandinavia. As I sat in the cab, I imagined what it        control if I needed to spread the material from the
      that is apparent is that it is a fair weight to be       would be like to put a pre-cast inspection pit into         bucket, rather than simply dumping it.
      slewing at full stretch over the side of the tracks,     the ground. I don't really need a square hole and it            One thing struck me when using the bucket in a
      with a long bucket making things worse. My initial       might prove beneficial to slope and flatten one side        face shovel position. Normally you would reverse
      ham-fisted warm-up saw a track lifting, until I          of the excavation to allow easier access when it            the bucket in a fixed quick-hitch to carry concrete
      mentally reduced the working envelope of both man        come to lifting and positioning the elements.               and the like, but this puts the strain on the wrong
      and machine.                                                  I might also want to build a specifically-shaped       set of bucket pins. Rotating the bucket to accept
            Focusing on using the attachment, the              spoil heap as I go, or excavate a trench at an odd          concrete keeps the strain on the set of bucket pins
      integrated proportional sliding controls on the          angle. This would be particularly useful if I was           that were designed to carry the majority of the load.
      custom joysticks felt intuitive to use and I quickly     working tight in against a boundary line, but could
      picked up the basics of how to control the various
      movements of the bucket. Then I had to factor back
                                                               equally mean that I would have more freedom on
                                                               where to position the excavator in the first place.
                                                                                                                                       Better insight
      into the equation the standard bucket curl function,          If I had pallet forks and a grab I really don't need       This short spell at the controls gave me a better
      then the movements of the dipper and boom, then          the close support of a telehandler and I bet I could        insight into what a couple of proper operators have
      get my brain around how the relationship between         save the expense and risk of another labourer on this       said to me over the years; that it takes a couple of
      bucket and soil would change as I slewed. Trying to      job; the banksman and myself could handle the work.         weeks of intensive after-hours practice, with no-one
      work out how this relationship would change again             Those operators with experience of working             looking, before they can get their heads fully around
      if I offset the boom made my head hurt.                  with titling and rotating bucket hitches excavate           the concept. Not how it works – that's easy – but
            The thing is that the working envelope of this     differently to the norm. In many ways it is a more          exactly what they can achieve by approaching the
      combination does not consist of a series of              natural movement, mimicking the full range of               task in hand from a different perspective. But soon
                                                               movements of the human hand and wrist. Imagine              they are constantly using the tilting and rotating
                                                               building a sandcastle with a spade at the end of a          functions at work, not simply because they can, but
      Learning how to operate                                                                                              because it is the best way to get the job done.
      a tilt-rotator is one
      thing. Figuring out
      exactly what you can do
      with this new-found
      functionality is another.


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