In recent years users of truck-mounted loader cranes appear to have become more conscious of the need for regular, scheduled maintenance. In the UK, at least, this is perhaps a reaction to the introduction of the Lifting Operations & Lifting Equipment Regulations (LOLER) in 1998.
Ten years ago, when asking operators for details of their maintenance regimes, it was fairly common to hear responses like: ‘My truck dealer does it every time the truck has its six-weekly inspection’. Further probing would usually reveal that this consisted of a quick blast with the grease gun on the parts of the crane which were easily accessible, followed by a good lathering of grease on the stabiliser beams and jib extension slides. Thisis akin to going to the dentist with ear ache. To be fair, as soon as maintenance requirements were explained in detail, most users would then be prepared to consider a more disciplined approach in the future.
A proper maintenance routine consists of carrying out the required tasks at the right intervals. The first thing is to ensure that service intervals are scheduled in accordance with manufacturer and industry recommendations. The general rule applied is that loaders in application category B2 (on hook duty) should be serviced twice a year. Loaders in category B3 (on general lifting and light grabbing duties) should be serviced three times per year and loaders in category B4 (on arduous grabbing duties) should be serviced four times per year.
In addition to servicing or maintenance, a record must be kept of examination and testing. LOLER requires that a ‘thorough examination is carried out on an annual basis by a competent person’. It is the responsibility of (and at the discretion of) this competent person to determine whether it is also appropriate to carry out a dynamic load test. This would often be necessary if, for instance, the loader had been repaired after a structural defect. Notwithstanding this , the crane should still always be tested at maximum intervals of every four years; and there are various schools of thought about the benefits of testing. Some feel that it is potentially detrimental to subject cranes to overload situations more than necessary.
The biggest issue is how to determine who is a ‘competent person’. A common definition is ‘a person who possesses sufficient knowledge and experience’. But this does not really help. And how competent is the person who decides whether the competent person is competent? An important task lies ahead therefore and is currently being considered by the UK trade association – the Association of Lorry Loader Manufacturers and Importers (ALLMI). ALLMI is working to establish a benchmark or standard that can be applied across the industry, possibly involving some form of examination or regular audit. This will be welcomed when it arrives but in the meantime please be assured that a truly overwhelming percentage of service engineers in our industry are knowledgeable, experienced and ethical.
What should a service consist of? This can depend on a number of factors, but mainly it depends on the type and level of application. For example, a loader on arduous grabbing work requires more maintenance than one which is just on hook duty.
A typical service should start with operating the loader to establish whether there is wear in pins and bushes, or leaks on rams and valves. The golden rule of hydraulics, of course, is clean oil. Oil change intervals again vary, but one to two years depending on application is a good practice and filters should be changed on every service.
A detailed list of checks should include the subframe, mounting bolt torque settings, PTO/pump, stabilisers, hoses, valve block, rams, wear pads and so on – from one end right to the other. Importantly, further checks must be made on the safety system of the loader, the complexity of which can vary dramatically from one brand to another. For example, service engineers might be able to download key operating statistics such as running time versus working time or number of overloads versus number of lifting cycles and so on. This information can often be used in a way that is constructive for the operator and manufacturer alike.
Documentation is also a major part of the equation. Many companies use a triplicate pad/check list that confirms checks and adjustments/repairs made, plus recommendations for any further work required. This means that a clear audit trail is established and the operator, the owner and the service company all have a record.
As part of the growing demand for the aforementioned audit/responsibility trail, a number of manufacturers now offer fixed price maintenance schemes. These vary, depending on the customer’s requirement, but often will mean that for a regular monthly premium (usually index linked or inflation protected), the manufacturer will provide a comprehensive servicing regime covering all routine maintenance, all subsequent repairs and associated spare parts, breakdowns and so on. Properly managed, this brings benefits to both crane owner and manufacturer.
Under a fixed-price maintenance scheme, it can be to the benefit of both manufacturer and crane owner to carry out more than the recommended number of services. This may sound strange since it implies a higher spend on maintenance, on both sides. But scheduled preventive maintenance saves money. Changing a hose before it is right down to the wire significantly reduces the chances of a call-out on Friday evening rush hour. Changing a hose during a service is approximately one fifth the cost of it blowing on site. More major problems can also be spotted before they become serious. The old adage ‘a stitch in time saves nine’ is never more appropriate.
Crucially, most crane owners would always prefer to stand the loader down for scheduled maintenance than have it unexpectedly out of action due to a trifling, preventable breakdown. This is where experience and knowledge are worth paying for.
Finally, apart from adhering to the recommendations above, what can the crane operator do to look after his loader on daily or weekly basis between services? Regular greasing is important, as is a thorough visual inspection of the machine before and after carrying out any lifting operation. Stowing the loader correctly for transit (and for tipping) can also play a key role in reducing wear and tear both on the structure and pivot points.
A great deal of sound advice is available from the ALLMI code of practice, which is the foundation for much of BS7121 part 4 and other documents.
