Cranes and Lifting gets and inside look at the Humma range of pick and carry cranes.
The Humma range has evolved from its foundation in 1996 to producing a range of models, culminating in the release of the worlds largest articulated pick and carry crane with auto levelling.
Cranes and Lifting Magazine was interested in the plans for the range and how the new Humma 55t will impact on the industry. We spoke to DRA Industries founder, Peter Dalla Riva.
CAL: DRA was established in 1971 and was operating in other industries when the Humma project was launched in 1996. Why was the pick and carry crane market chosen when DRA had no design background and knowledge of the market?
PDR: In 1984, DRA acquired Construct Engineering, an experienced design and build business in the field of material handling. The in-house experience both at the engineering and manufacturing level was high and diversified under DRA stewardship. Construct expanded, carrying out design, build, install and commissioning projects throughout Australia and later overseas in New Zealand, Ireland, Botswana, India, Qatar and Italy. The flow of overseas projects diminished and with a skilled group of staff it was necessary to find alternative work or retrench. Rather than lose the company’s skill level, other engineering markets were investigated. Following an Australian wide survey, the pick and carry crane market was chosen, as the industry confirmed it was open to change. At the time, there was only one manufacturer, Franna in Brisbane, the other was Linmac in Perth which had recently ceased operations. The first Humma 18 was built in 1997.
CAL: Without experienced crane engineers how was the Humma specification and design established?
PDR: It was a steep learning curve. During the period 1998/2000, pick and carry crane owners and others, made jokes about Construct Engineering and the Humma when early models had occasional breakdowns in the field. We saw it as being part of debugging of early designs.
The design team had not designed a crane with the exception of an engineer from Linmac, but the range of design experience was considerable over a variety of industries, food processing, cereal storage and transfer, fertiliser blending, storage and dispatch and a range of specialized items of plant. One such item of plant is the hyperbaric chamber at the Fremantle Hospital for treating burns patients. With this wide range of expertise the Construct engineers adopted a specification and design criteria not used by either Franna or Linmac and unknown by the market. Even today, Humma has difficulty in gaining acceptance with some buyers after more than twenty years of manufacture.
Your question goes to the heart of design and specification when designing manufacturing plants and machines. The design criteria includes that it must be safe to operate, it must be reliable as often they run 24/7 and componentry must be quality extending the working life before major overhauls are required. The buyer will consider all of the costs to the major overhaul, purchase price, maintenance, downtime and operating costs. Humma takes all of the above into consideration and more, and after twenty years of operation there is the proof. The air suspension, minimal wear and no replacement on any Humma to date, articulation joint after fifteen years one millimetre wear and no line boring required and fabricated boom damage is rare and only when operators exceed the design safety limit.
CAL You have explained how the engineering teams’ experience in other industries is adopted in the Humma design, but were there specific design and objectives?
PDR. Yes, there was a range of technical criteria covering safety, reliability, low running and maintenance costs and a design capable of being used on all future model. If you look at all Humma models, from 20t through to 55t, the footprint is the same only the size changes to suit the lifting capacity. Standardisation was an integral part of the design criteria set in 1996. Also, the initial plan was to build about thirty Humma over a period of a few years, having them available for dry hire, for heavy construction and maintenance in the mining industry. There was no plan to sell the crane’s various models as they were developed in the initial ten years as this would enable Construct to track performance and incorporate the upgrades into new models.
The 1996 specification has been followed and the benefits are now well proven. Take the footprint, it has become heavier with size with no warranty issues as debugging of earlier models has increased reliability dramatically. Because of the design changes all current models 25t, 35t and 55t do not have a problem attributed to standardisation. The air suspension introduced in the design specification in 1996 was laughed at and industry operators said a crane must have a rigid leaf spring suspension because Franna and Linmac cranes used them. The opposition could not offer any technical reasons why air spring could not be used. Construct designed and tested a number of versions and, yes there were failures in the field. The development cost was high but perseverance won the day, the Humma air suspension has contributed to the quality and performance it has shown over many years.
Damage to the crane when working comes down to operator misuse such as over-lifting. The major damage occurs when the crane is driven especially at high speed. The air suspension confines the road conditions to the axles as the air spring absorbs most of the vibration and does not transfer it to the crane structure, this destroys bearings, cracks welds, enlarges the articulation joint, increases cabin noise and loosens bolts and fittings.
Leaf spring suspension exhibits all of the above problems and although this model of crane should not exceed 80kph, if this is exceeded the driver can lose control when vibration is high. Air spring as designed and installed in all Humma, has been tested at 105kpm on Humma 35 with the driver having full control.
Modular construction was another design feature to enhance the speed of manufacture in the case of the cabin, ease of assembly, ease of replacement in the event of a turnover and by mounting on rubber supports reduces cabin noise from engine and road whilst driving. The noise level is well within the standard at 65 to 70 decibels.
The industry survey established that the market wanted a crane with fully powered booms which did not exist, larger reach, heavier lift capability, more comfortable ride, greater reliability, lower maintenance and operating costs and increased safety.
It has taken time, but Construct has met all of the survey and more, worthy of mention is the automotive Cummins engine used in all three models, as is the driveline. The engine power can be electronically adjusted from 230hp to 315hp. Apart from saving in standardised parts the engine has been tested against industrial versions achieving up to 25% lower fuel consumption with lower pollution.
CAL: You have covered the Construct team achievements, so before we address Humma 55 development, how do you see Humma in 2019?
PDR: It has been a long, expensive road with many technical obstacles and a number of setbacks, but we now receive regular positive feedback resulting in orders for all three models.
Between 1996/2000 the market was small, MAC25 had been released but the market had been starved of R&D and innovation, the AT40 was developed but not yet seen. Construct had just commenced and by 2017 had gone from Humma 18 to five models culminating with the most advanced in Humma 55. In 2018 this model completed twelve months of field trials. The Construct team and management have pursued the original specification of one footprint for all models, modular construction and improvement in each model. The industry is seeing that Humma has a high degree of safety, offers the longest reach, has the highest lift capacity, established high reliability, low wear with low maintenance, comfortable ride and very low fuel usage. All designed and manufactured in Australia using quality componentry by an Australian company about to celebrate fifty years of trading. The commitment to R&D is entrenched and yes, the initial buy price is not low, but all other ongoing operating costs more than offset the difference.
CAL: Humma has introduced new technology to the pick and carry market, but how did Humma 55 come about? It is a big jump from 35t to 55t.
PDR: The answer is we listened to the market. MAC25 was well established in the mining industry but with heavier components being installed in mining equipment, the need for heavy duty pick and carry existed in the range of 35 to 40t. Humma 35 could meet some lifts but not all. Discussing the requirement with Rio Tinto and BHP maintenance, a crane capacity of 40T appeared to be ideal. As most Hummas are in the construction and mining sectors, the Construct team prepared a specification for a Humma capable of lifting and moving a weight in the range of 50t to 60t. It also had to be suitable for driving on the road. The established and proven footprint could be used and enlarged for Humma 55, the drivetrain was well proven and in use in the 25t and 35t. However, it was evident was that lifting weights up to 55t needed a very confident and safe operator and this could be a problem. The design team developed controls that de-skills the crane operation, giving the operator maximum visual load control and crane control whilst moving the load and this led to the development of the dynamic load chart and the dynamic hydraulic suspension.
The 2018 field trials confirmed these innovations greatly increased the safety of the crane. The design team had the benefit of twenty years of development using the 1996 footprint but had the challenge in establishing loadings for tyres, rims and axles. Humma 55 has an 80kp/h road speed and the combination of hydraulic and air suspension produces a safe and comfortable ride.
Since its release, we have been surprised in the demand for infrastructure projects, upgrading state rail lines, road bridges and tilt panel positioning. It appears other uses will be found by the crane industry although the market is mining services and maintenance.
This four million dollar R&D project was launched not only to meet the demand of a specific market sector but to see if the pick and carry crane industry was ready to move to larger cranes. Monitoring Facebook responses and the level of enquiries, it appears it is. The design team see no technical impediment to building a 100t crane, if the demand arose.
CAL: The crane industry will be looking to see Humma 55 in operation. When will the first unit be delivered and are you concentrating on mining?
PDR: Humma cranes can be found on a number of sites in Australia and Papua New Guinea. The common models are the 25t and 35t with Humma 35 being the preferred model. Humma is found at ALCOA, Rio Tinto, Harmony Gold, Newcrest Gold, CPB Contractors, John Holland and many others. Humma cranes are also sold and dry hired to contractors carrying out major contracts. There were six Humma 35s on hire to CPB Gorgon Project for up to five years. The first of eight Humma 55s is scheduled for delivery early 2019 to Victoria.
The DRA company is not considering large production as its success is quality, service and innovation. Existing Humma owners will have preference as they have been loyal and supportive, however we would like to see it in other markets.
CAL: Having developed the flagship Humma 55 is it the end of R&D for Humma or are there other projects scheduled. Where to now for Humma?
PDR: Humma has reached the first objective to produce the safest, most reliable and efficient range of heavy lift cranes.
The second objective is to reduce fabrication costs so as to ensure manufacture remains in Australia, we are now the only Australian owned crane manufacturer and our challenge is to reduce costs. This is already being addressed with the first automated welding cell scheduled for installation and operation by June this year. The majority of the welding on the crane will be done by the robot, which is capable of working 24/7 if required. It produces consistent quality welds and reduce manufacturing time. No doubt, there will be problems and it will take time to maximise efficiency, but it is a challenge we look forward to.
The third objective was launched in December 2018 when Construct Engineering entered into a Distribution Agreement with Australian Crane & Machinery (ACM) to distribute and service Humma.
Since the inception of Humma, Construct has sold and serviced Humma because we wanted to monitor the performance of each crane. This has proven invaluable in assisting in the debugging and upgrading of each model. ACM has sales and servicing facilities in most states and is experienced with handling other makes of cranes. Existing Humma clients can be serviced by Construct or deal with the ACM team.