By Craig Walker
If you’ve ever pinched your finger when bolting items together, you know the feeling’s unpleasant. I had a painful pinch reattaching the rear wheel of my son’s bicycle after repairing the flat. I can only imagine injury from pinching a finger when bolting the tower of a wind turbine together. Lucky for me, the only damage was a small blood blister but wind technicians and manufacturers face a greater risk of serious injury. In fact, hand injuries from misuse of tools are the number one cause of injury for wind techs.
When a tech assembles or repairs parts of a wind turbine, he or she typically uses powerful hand tools that are heavy and harmful if used incorrectly. Hydraulic power-torque wrenches have pinched off fingers because of improper use. Bolts can easily be over torqued and broken if the settings are incorrect, potentially causing harm.
While it’s important to follow a tool’s safety instructions, claims may be misleading. A manufacturer may use the term “ergonomic” or “ergonomically designed” without fully verifying the claim. What’s more is that wind farms are typically in remote locations, nowhere near hospitals or emergency care. This means medical attention, if needed, may be hours away.
So the best course of action is prevention: know your tools, assess the risks, and apply proper safety procedures — then double-check settings and positions for good measure.
Here are three tips that, if applied, may make bolting tasks safer and more efficient.
1. Choose one to get it done
If a job requires multiple tools, such as bolt tensioners, as well as torque and impact wrenches, consider a minimalist approach. This reduces the chance of mistakes when swapping one tool for another. For example, depending on the task, one electric tool may replace several pneumatically powered ones.
Although pneumatic tools may offer a better power-to-weight ratio, demand for electric tools is increasing because of improvements in capability and accuracy (meaning the precision with which the tool delivers torque). For example, Norbar says its EvoTorque 2 electric-torque multiplier delivers torque to within 3% of its setting. It is also extremely compact, which is a benefit to those working in the confines of a nacelle.
Electrically powered tools can be corded or battery powered. The battery powered ones are typically safer (no cords to trip on) and easier to use (with a simple on & off switch). New models may also offer considerably longer run times, thanks to advances in lithium-ion batteries. One other plus of going electric: no pump or hoses.
Of course, it is important to choose the ideal tool for the job whether it’s a pneumatic or an electric device. However, if it is possible to limit the number of tools brought uptower, this may be the safer choice.
2. Keep it in the family
To increase efficiency and safety, consider selecting tools from one manufacturer. Companies develop products with a unique approach to ergonomics, control systems, and safety lockouts. User interfaces on digitally controlled tools also vary by brand, so it’s advisable to stick with one manufacturer when possible.
It’s all-too-easy to miscalculate torque values or mistake degrees of rotation when using similar tools but from different manufacturers. Familiarity with one brand may reduce such errors.
Fortunately, advances in manufacturing mean tools are becoming smarter. For example, bolting manufacturer HYTORC says its LION Gun precision bolting system offers built-in data recording.
This means users can track and log completed bolting jobs for later reference. In addition, Norbar’s EvoTorque 2 “memorizes” multiple targets, readings, and user IDs, which increases tool (and user) accuracy and accountability. Take advantage of such built-in features to increase tool safety.
3. Look, no hands
Techs that use hydraulic torque systems typically work as a two-person team. One technician operates the hydraulic pump control switch, while the other person correctly positions the hydraulic tool for the job.
To do so safely and effectively, both techs must communicate clearly, which is often a challenge in noisy or confined workspaces. However, as Hands Free Bolting company points out, if a pump is accidentally operated at the wrong time, it may result in the tool operator having fingers or hands trapped between the tool and reaction point.
To prevent such incidents, the company has designed safe bolting accessories that are compatible with all major brands.
For example, it offers a Back-Up Nut for these two-person jobs, which lets one technician step away from the torque wrench after it’s positioned onto the bolt. This allows safe, hands-free operation of the pump and reduces the risk of a dropped object.
Hands Free Bolting also offers a Safety Valve that fits between the hydraulic power pack and hydraulic torque tool. If the trigger is released, hydraulic power is automatically cut so the tool operator can re-locate the tool without concern of accidental tool activation.
The danger of power tools is evident in the thousands of emergency room visits they account for each year. Many of those visits are caused by misuse of tools or failure to uphold safety standards.
Always follow the manufacturer’s instructions, inspect and maintain tools before use, wear personal protective gear, and know your work environment.