Product Group Report: Tower Cranes

Size: px

Start display at page:

Download "Product Group Report: Tower Cranes"

Alyson Rosanna Evans
5 years ago
Views:

1 Product Group Report: Tower Cranes A study of the remanufacture of static lifting equipment in the UK Written by: Adrian Chapman Date: April 2009 Page 1 of 10

2 Page 2 of 10

3 Contents _Toc Overview Background Market Safety Used Tower Crane Market 6 2 Value 7 3 Evolution rate 7 4 Reconstructability 8 5 Potential 9 6 Recommendations 9 7 Conclusions 10 Page 3 of 10

4 1 Overview Cranes are predominantly used for lifting within the construction, manufacturing and transport industries, with a variety of different machinery developed to meet the needs of these sectors. Common examples of crane machinery include; cherry pickers used for access to elevated work sites, hoist type cranes used for the movement of stock in warehouses and tower cranes used for large scale construction projects. In this report the new and used UK tower crane market is described, and reuse and remanufacture activities are discussed. 1.1 Background Tower cranes are most commonly used for large construction projects where substantial lifting capacity is required over several weeks or for unique circumstances which need a combination of large lifting capacity and height. Projects with these requirements specifically require the capabilities of a tower crane, or are substantial enough to justify the additional installation and disassembly costs compared with a mobile crane. Assembling the structure of a tower crane on site is necessary as they are too large to be transported as a single unit. Instead, they are manufactured in several modular sections which are fitted together, allowing efficient storage, transportation and assembly. The main metal structural sections (e.g. mast and boom) form the core of the crane; these sections are well maintained due their high value, structural importance and inherent significance to safety. The condition of these sections defines the lifetime of the crane, and these form the core. Some sections are viewed as semiconsumable, for example electric motors, as they will require replacing infrequently during a crane s lifetime. Other parts, such as the wire ropes, are considered fully consumable and are replaced regularly as continual maintenance on these parts is not deemed economical or safe. 1.2 Market Globally the manufacture of tower cranes is limited to a few well established OEMs such as Manitowoc and Liebherr. The nature and demand for tower cranes is such that OEMs operate a small number of large manufacturing facilities which supply cranes to many countries. This provides OEMs with enough flexibility to meet fluctuating demands in different regions. Within Europe these manufacturing centres are located in countries such as Germany, Italy and France. No manufacture of tower cranes takes place in the UK, and OEM activity is limited to sales, replacement parts and servicing. Page 4 of 10

5 The global and UK market for tower cranes is strongly influenced by the strength of the construction industry, and particularly the number of large construction projects. Tower cranes are not usually bought directly by construction companies; instead it is more economical for construction companies to lease cranes from specialise plant hires. These hire companies purchase their cranes from the OEMs, and maintain a fleet of cranes to provide access to a wide variety of crane specifications suitable for different projects. This allows construction companies to use the most suitable crane for a specific job. Within the UK there are 20 to 25 large hirers, for example Select Cranes, Falcon Cranes and City Cranes. In total these companies own approximately 1,750 2,250 cranes, which is the vast majority of the UK tower crane population. Typically 70-80% of these cranes are in use at any one time. This figure is much lower at the time of this study due to a declining number of construction projects. This fall off has impacted the number of new tower cranes being sold; OEMs indicate that they expect very few sales will occur in the short term, but the market will pick up once new construction projects begin to start again. 1.3 Safety One of the major influences on tower crane manufacture is the structure s reliability and safety. The production of tower cranes is covered by strict quality and safety standards set out in the European machinery directive; all cranes sold within the EU must conform to this directive and bear the relevant CE mark. Tower cranes must also undergo regular inspection and maintenance to ensure they are fit for purpose, and there are ISO standards to cover this. Each crane is inspected every time it is erected and dismantled, as well as frequently during use. Maintenance is performed regularly between jobs, with parts replaced and small amounts of re-welding performed if necessary. Within the UK standards are stricter, partly due to recent high profile accidents, and there is now a British Standard associated with the use of Tower Cranes. Regulations have been further reinforced by the Construction Plant-hire Association s Tower Crane Special Interest Group. This group has recently published substantial guidelines, best practice guides and technical notes related to the use and maintenance of tower cranes. They have also announced plans with the Health and Safety Executive to start up a UK registration scheme for tower cranes. One particular area of concern over tower crane safety is focused on the performance of the structure, which degrades over time due to metal fatigue. The age of a crane is not always a good indicator of the extent of this fatigue as factors such as weights lifted, frequency of use, location and maintenance affect the condition of the metal. Representatives from the industry indicated that a lifetime of 20 years is possible, but this is not generally acceptable in the UK where many companies will remove cranes from their fleets after 10 years due to safety considerations, (though different companies have slightly different criteria). Safety concerns are further demonstrated by some construction projects which specifically require the use of new or cranes which are less than 5 years old. Page 5 of 10

6 1.4 Used Tower Crane Market Industry attitudes and the strict guidelines described above have had a considerable influence on any potential second-hand crane market in the UK, and have lead to very little demand for them. A used crane is unlikely to be purchased by a UK company as they have low confidence in the value of these cranes. Instead, cranes from the UK will be sold on through brokers, auctions and OEMS to companies outside the UK where safety standards are not as strict and attitudes are different. Outside of the UK there is an active used crane market in certain parts of the world, though often these cranes are sold as seen, with little or no repair or refurbishment work. Industry representatives agreed that cranes bought in this way from the UK are still safe to use as reputable firms will not sell on unfit equipment and maintenance records are normally available. If a crane from the UK is not safe to sell on, the owner will strip down the crane, scrap the structure and salvage useable non-structural parts for spares. The only regular purchasing activity of second-hand cranes identified within the UK occurred when a specific crane was required for a one off job. In this situation a used crane may be considered assuming it was close to new. A further factor influencing this market is the recent appearance of counterfeit cranes and crane parts. These are generally of lower quality, and do not always meet safety standards despite appearing to be authentic. This activity has aroused suspicions by buyers and has lowered their confidence in used parts as it can be difficult to verify their origin or be certain of quality. UK tower crane OEMs, users and other experts indicated that the attitude shown towards remanufacturing in the industry was similar to that seen towards used cranes. No remanufacturing activity was identified in the UK, and industry representatives stated that, despite some possible benefits, it was unlikely that remanufacturing would become commonplace. The overwhelming view was that even with guarantees from the remanufacturer crane purchasers would never have the same confidence in the safety of a remanufactured crane as they would have with a new crane. It was also believed that remanufacture would confuse already complicated safety issues, and would essentially backtrack on recent steps taken to improve the safety and credibility of the sector. The remanufacturing process was also considered uneconomic: To achieve the same quality as new, a crane would need to be fully stripped down and each section tested for metal fatigue. It was estimated that this task would take in excess of a month, with additional time required for the reconstruction process. It was clear that environmental concerns were seen as having little consequence when compared to these other factors. Though there is no remanufacture activity occurring within the UK tower cranes industry, it should not necessarily be seen as wasteful. The industry is strongly influenced by health and safety concerns and rather than undertaking end-of-life remanufacture, extensive ongoing maintenance is performed on cranes to prolong life for as long as is deemed safe. Parts are replaced or repaired at any sign of wear and tear and structural joints can be re-welded as necessary. There is evidence that semi-consumable items, which do not last as long as the structure, can be repaired; for example the wire coils in the various electric motors can be Page 6 of 10

7 rewound to fix them and increase performance at the same time. The scale of this activity is difficult to determine as hire companies do this on a case by case basis keeping an inventory of spare parts. Globally OEMs do undertake some refurbishment work and a small amount of remanufacture occurs at specific sites abroad. One of the larger OEMs has recently opened a repair and refurbishment centre in Portugal, handling an estimated 35 cranes per annum. Cranes are sent to the site due to customer trade-ins, a change in operating conditions or the need to repair major damage. Despite the availability of this site only two cranes from the UK have gone through the process offered by this particular OEM. These cranes were damaged and required major repair, which was economically viable as the cranes were close to new. In addition to this low level of remanufacturing activity, some electronic control mechanisms can also be salvaged and sent back to OEMs for remanufacture or reuse in new cranes Overall the remanufacturing in the tower crane industry is limited by safety concerns and the extensive maintenance occurring which ensures they are used until they have reached the end of their potential life. The overwhelming feeling was that this was unlikely to change, and it was more likely that the industry would move in the opposite direction towards more safety assurances. 2 Value Currently there is little or no value associated with the remanufacture or reuse of tower cranes within the UK. Only in exceptional circumstances, when there are appropriate safety and economic reasons, will cranes undergo remanufacture. We estimate that <1% of the UK tower crane population will be remanufactured, all of which takes place abroad. However, there is a large value associated with ongoing services to maintain cranes and keep them operational for their safe working life. 3 Evolution rate Many areas of tower crane technology are evolving to improved performance, safety and speed. Improvements in crane structures are allowing the lifting of Page 7 of 10

8 greater weights by smaller lighter cranes. More recent designs such as flat top cranes and self-erecting cranes are decreasing the time it takes to erect a crane and also improving lifting capability in difficult or constricted sites. There is also a trend towards the use of more electronic controls, providing facilities such as a remote control. These developments are not always viewed as enhancing performance, and are also believed to make repairs more difficult as more specialist knowledge and parts are required. However, one specific area of improvement highlighted within crane electronics was the efficiency of electric motors. These have now been developed towards having a lower power consumptions compared to years ago. Rather than revolutionising the industry these new technologies are gradually replacing some of the existing fleet as older cranes are taken out of service. Large scale disruption in this industry due technological development is not anticipated in the future. 4 Reconstructability The modular design of cranes means that they are inherently easy to dissemble into different structural sections. However, the individual structural sections of a crane are manufactured to a high quality due to the importance of the structure. These sections are not designed with individual reconstruction or remanufacture in mind. Full disassembly into the smaller components and subsequent reconstruction is far more labour intensive than assembling the crane from modular sections. Also, the condition of the metal is generally unknown, as metal fatigue varies with lifetime, usage and location. Extensive testing is required on each section of metal prior to reconstruction to ensure it meets strict quality and safety standards. Cranes are designed to allow replacement of various parts considered consumable or semi-consumable. These parts will be replaced throughout the crane s lifetime, and have been designed to make this easy. In the case of the electric motors, they are also commonly reused as they are relatively easy to repair for reuse. Hirers keep an inventory of these replacement parts as spares to decrease down time. Page 8 of 10

9 5 Potential In the case of tower cranes, the relatively simple design of the structural frame does not lead to easy remanufacture. Whilst it is easy to rebuild sections of a tower crane, doing so to produce a section which has acceptable safety tolerances is a significant task, and incurs a corresponding large cost. Throughout the service life of a crane its condition is maintained to a high standard and once it reaches the end of its life it has been well used. Therefore, concerns about the structural integrity of a remanufactured crane will exist with purchasers, hirers and safety representatives since it is perceived as having been used. These attitudes are unlikely to be overcome in the near future, and anecdotally the opposite appears to be occurring due to growing safety concerns about the reuse of parts. There is precedent for remanufacture by OEMs undertaking some activity, but this is on a small scale due to economic viability and takes place abroad. For these reasons there appears to be very little potential for increasing the quantity of tower cranes remanufactured within the UK. 6 Recommendations After discussions with industry representatives it is clear that the tower crane sector is not receptive to remanufacture. The key reason for this is the safety issues associated with the crane s structural condition after its normal lifetime. These factors also demand additional remanufacturing stages and increase the complexity of the process, requiring testing to reach the suitable safety standards. The scale of this work reduces the financial benefit of remanufacture, and it is not seen as a profitable area; this is unlikely to change in the future particularly as the cost of new cranes is currently dropping. Even with financial incentives in place, industry representatives felt that safety concerns could not be overcome regardless of the quality of remanufacture. It is difficult to foresee any way of altering the opinion of this industry in the short to mid term. Therefore, engagement with OEMs is one possible way to develop this area. Some refurbishment facilities exist already and OEMs could be encouraged to extend this provision further. Suspicions about low quality counterfeit crane sections and parts are also influencing the reuse market, as this drives purchasers in the UK and abroad to preferentially buy from the OEM. Further reuse may be encouraged by the introduction of better mechanisms to verify a part s authenticity, for example RFID Page 9 of 10

10 tags. These measures could be tied in with improved maintenance and usage records. Similar suggestions have already been put forward within the industry as part of a drive to improve safety. However these measures could have the knock on effect of encouraging buyers to consider purchasing a used crane as they would have more certainty about crane or part s origin and condition. However, in the short term it is likely that the majority of used cranes will continue to be sold on abroad. Many issues stem from the uncertainty around the working lifetime of a cranes structure. Independent studies with a focus on remanufacture and reuse could be conducted to asses the way in which the structural integrity degrades over time and use. This information could provide valuable information to a purchaser seeking to buy a used crane. However, one of the major issues raised was that each crane has a different working history; therefore drawing generalisations is difficult and potentially dangerous. As suggested previously, better recording of a crane s use may go some way to solve this. 7 Conclusions Tower cranes are used extensively within the construction industry, particularly on large building projects. Our research indicates that there are around 2,000 tower cranes in the UK, with the majority owned by large leasing companies. Typically these will be replaced every 10 to 15 years, due to safety considerations. Concerns about safety and related legislation strongly influence the purchase of second hand or remanufactured cranes, and there is no market of note within the UK. Additionally, remanufacturing a crane s structure is uneconomic due to the extensive work which would be required to fully produce a crane which met the same standards as a new crane. Even with this process, it is unlikely that a crane would be considered as new by the industry. This attitude is unlikely to change in the short term due to the industry s concerns about public perception. Despite the lack of reuse it should be noted that this industry is not necessarily wasteful, especially when the safety requirements are taken into consideration. Within the UK, tower cranes are well maintained and used until local safety and maintenance factors mean it is not viable to do so. Many parts are replaced on a regular basis to ensure the crane continues to function over an extended period. There may be potential for encouraging reuse and remanufacturing of items such as the electronic motors in the future as it appears there is some activity occurring in this area already. However, it seems unlikely that the complete remanufacture of tower cranes is viable at present. Page 10 of 10

Presentation Overview. Background. Coast Crane Company Background. Coast Crane Company TOWER CRANE INSPECTIONS

Presentation Overview. Background. Coast Crane Company Background. Coast Crane Company TOWER CRANE INSPECTIONS TOWER CRANE INSPECTIONS Presented by Mike Heacock Coast Crane Company Presentation Overview Background of Coast Crane and Mike Heacock Review common tower crane types Pre-delivery inspections for new tower