Safety in hydraulics

Hydraulic equipment can potentially pose serious risks to safety. However, an awareness of the most common faults, and also the safety features offered by new technology, can minimise those risks, says Nigel Ord, General Manager of Fluid Power at ERIKS.

Safety is of paramount importance when dealing with hydraulic systems; this is especially true in areas such as mining, quarrying, recycling, construction and offshore, where the operating environment puts hydraulic equipment under considerable daily stress and makes routine maintenance difficult to carry out.

To protect the users of hydraulic equipment, measures are being taken to embed safety as part of company culture within each engineering industry concerned. Likewise, hydraulic safety is increasingly becoming a fundamental part of component and machine design, to prevent, for example, the wear and abrasion of hydraulic hose that leads to safety-threatening leaks, contamination and fire hazards.

A major risk to the safety of engineers is the high level of fluid pressure that is typically found in hydraulic applications. A sudden release of high pressure fluid can cause serious injury; indeed, the most common injuries caused by hydraulic equipment result from pinhole leaks in hoses. A typical example of poor practice is observed when operators look for pinhole leaks in hydraulic lines by running a hand or finger along the line. If a leak is found, the pressurised fluid can penetrate the skin with the ease of a hypodermic syringe - an unpleasant image but a useful one if it lingers in the mind and deters engineers from undertaking any such manoeuvre. So serious are the consequences of high pressure fluid injuries that ERIKS, in conjunction with the British Fluid Power Association (BFPA), has launched a course to instruct anyone who works with hydraulic machinery in the safe installation and maintenance of such equipment.

By following best practice guidelines and applying a common sense approach, risks involved in operating and maintaining hydraulic equipment can be minimised. For example, always keep your hands and body well away from leaks and components that might eject fluid under high pressure and, when checking for small hydraulic leaks, move an object such as a piece of cardboard or paper across the area in question, rather than naked skin.

From a broader perspective, be proactive, rather than reactive, when it comes to maintenance. For some, waiting till equipment fails may seem the most economical option, the theory being that this allows plant production to remain uninterrupted and extracts the maximum use from components before they are discarded. In reality, a scheduled replacement is far more cost-effective than, for example, hose assembly failure at an inopportune time, while the safety risks of running hose assemblies that are beginning to crack, blister and bubble is at best inefficient and at worst dangerous, particularly if there are people working near the worn hose.

As well as considering best maintenance practices, be aware of component quality; safety needs to be designed in from the outset, which is why legislation and guidelines, including the Pressure Equipment Directive, requires manufacturers of hydraulic equipment and components within the EU to provide machine builders and end users with safe equipment.

Another important issue, and not one of those most commonly raised when safety issues are discussed, is skin health. Repeated contact with oils and greases from poorly assembled equipment can cause serious skin disease in machine operators. One such disease, contact dermatitis, a common risk in quarrying and mining, is, according the Health and Safety Executive (HSE), the cause of 70% of skin conditions reported. Frequent contact with diesel, oils and grease can easily lead to the development of contact dermatitis and so operators can take care of their employees by offering not only skin care products but also support materials that raise awareness and understanding of the issue. The HSE has even reminded employers that paying proper attention to the skincare issue comes under the legal obligation to provide a safe working environment.

By ensuring that hydraulic systems are correctly specified, installed and maintained, operators can provide safe and reliable equipment. And by maintaining good operating practices to support the wellbeing of engineers, including appropriate training to raise awareness of safety risks, uptime and productivity can be maximised.