May I see the Calibration Certificate for your Torque Wrench?
July 21, 2011 by Windpower Engineering
Filed under Editorial, Fastening-Joining for Wind Power, Mechanical Components
Many companies make the same mistake every year assuming their torque tools are accurate and in working order. They also assume factory torque charts are correct and a certified gauge ensures tool accuracy. It’s a hazardous assumption because calibrated power tools frequently are not performing as expected.
Although there are other ways of establishing the tension on a bolt, torque is used most often. Such tools include hydraulic and electric torque wrenches, torque multipliers, and manual wrenches. After the required yearly calibration, tool owners usually get a certificate detailing the particulars which also verifies the quality of the equipment.

Technicians with mobile calibration equipment say they can calibrate all makes and models of torque wrenches up to 25,000 ft-lb. The computer, just behind the Mobil- Cal technician, lets him sign into the company’s online system, identify the tools that need calibration, and follow the step-by-step ISO procedures for the task.
Certificates are also needed after turbine assembly. For instance, during mechanical-completion inspections, inspectors with OEMs must work through punch lists. The OEM inspector will look for training records and calibration sheets for the tools used. Also, internal quality reviews conducted by companies will need to see the calibration sheets. What’s more, companies go through a process to become ISO certified and having a documented calibration process is part of ISO procedures.
Most technicians keep the calibration forms handy in a three-ring binder–kept…somewhere. If proof of certification cannot be produced, the technician may be forbidden to use the tool on the job site until it is. That could be a problem for the technician who may have to resort to a manual tool for the day, and accept a significant loss of productivity.
Engineers at Alltite Total Bolting Solutions may have an answer to the problem in an online service that tracks tools, their calibration, and certification. One goal is to get rid of the easily lost certification forms and make them more readily accessible.

The MobileCal sample calibration report lists the values measured and calculated for a hydraulic torque wrench.
For example, the Customer Portal-Calibration chart lists all the tools in a particular facility. “This could be a single wind farm, a region, or all the tools that need calibration for a particular company,” says Alltite CEO Tom Smith (alltite.net). He adds that the program was devised with two sides in mind. On the calibration technician’s side, data and procedures assist with calibrating torque tools step-by-step to ISO standards 6789 and 17025.
Clients, says Smith, see and manage all their calibrations through the online portal. A user name and password lets customers access the data. Customers search by their calibration ID, printed on a sticker placed on their tool at the last calibration. Users might also search by calibration-due date, or the tool and equipment type. Smith says the program can be customized for particular needs.
Benefits are that the company’s quality-control person would see the entire fleet of tools to make sure they are compliant. The paperless system lets users get away from chasing the sheet of paper that usually comes with calibrations.
An alternative method at some large companies is to send equipment to its lab where it’s calibrated and sent back with a folded sheet of paper or calibration certificate. But the wind industry is so wide spread, says Smith, a technician could be in Pennsylvania one week and Minnesota the next. “If he’s hunting down this piece of paper, he’s losing time and money. With this system he can log into the portal, find the tool in question, pull up the certification in standard or metric units, and print or download it. It’s also viewable on smart phones.

The Expires column on the Calibrations and Search page of Alltite’s TorqueWare customer portal tells which tool in the fleet is next up for calibration.
The calibration reports show measured and calculated values, such as the torque to pressure ratio, as-found readings, as-left readings (after adjustments), serial number of the wrench, and more. “Another plus is it provides a quality program for an entire organization,” says Smith. “With the online system, it drives consistency across all business units and eliminates variance by having a single quality program. Without something like it, a company with 15 different sites could have 15 different vendors and possibly gaps in their quality program. This program wraps all calibration, certifications, and documentation into a single point which give clarity and consistency to the organization.
The portal also gives an inventory list so companies can allocate their resources. For instance, one site may have half of a company’s torque equipment, when in fact it’s more needed elsewhere. Smith says he’s yet to find a company that can track all its tools, and is 100% accurate. A frequent discovery, for example, is that more than 65% of clicker torque wrenches don’t meet OEM specifications.
WPE
How to fasten & join wind turbine components?
May 18, 2011 by Windpower Engineering
Filed under Fastening-Joining for Wind Power, Wind Basics
Bolting with regard to wind farms mostly concerns fastening the tower to the foundation and the turbine to the tower. The topic divides neatly into fasteners, accessories, and tooling.
Fasteners with tension indicators: Most bolts in a wind turbine are manufactured to OEM specs. The OEM also provides a torque value which the construction crew must apply to each bolt for a required level of tension. But because torque does not always correlate to bolt tension, bolt manufacturers have devised a range of devices for indicating tension.
One particular bolt design has an indicator cap on its head. Until the cap turns by hand with difficulty, the bolt is under tensioned. The device works by drilling out part of the bolt center and installing a tension indicator link to the cap. When tensioned, the bolt elongates, tightening the link and preventing the cap from rotating under finger pressure. Another design places a visual indicator in the bolt head. When the indicator is out of position, the bolt is under or over tensioned. The feature makes checking for tension a brief visual task.
Why torque control is a questionable way to achieve consistent pretension in structural bolts comes down to friction or what’s known as the k-factor. This is the relationship between the torque applied to a fastener assembly and the actual tension produced in the bolt. A short form of the relationship is:
Tension = Torque/kd where: k = k-factor, and d = diameter
K-factors vary from lot to lot, from bolt to bolt within a lot, and as a consequence of handling, storage, and lubrication. K-factors can range from 0.10 to over 0.20. Also, consider the variability of the torque tool. Manufacturers of tension indicators say it is likely that when using torque control to govern bolt tension that actual bolt tensions will vary ±40% or more.
Most industrial-fastener problems come from a bolt, cap screw, or spindle nut that has failed in service due to vibration, thermal cycling, or other harsh environment conditions. A few bolt manufacturers will design a prototype solutions and manufacture a locking system to accommodate load, corrosion, clearance, and material requirements. Customers, however, will have to test the prototypes to assure performance. Shaker or fatigue tests can often point to a best design when several are available. Users will be expected to specify the material, preload, and torque for their fastener applications.
A preassembled pair of washers provides a structural, self-locking fastener that prevents bolted joints from loosening by shock or vibration in high-stress applications. The device consists of two preassembled (glued for easier handling) washer-shaped pieces. Each has an inclined cam on one side and a series of ridges on the other. On installation, the cam sides are mated and placed between nut and joint material. Under vibration, the nut tries to rotate loose but, because the angle of the cams is greater than the pitch angle of the bolt thread, the interlocking cams and the non-slip ridges of the washer work together to create a jam which prevents loosening. The washer pair can also be used on bolts in either blind-holes or through-holes. In blind-holes, the washer pair is placed under the bolt head, while through-hole applications use the washers beneath a nut.
Reid Supply to Unveil New Products at IMTS
September 8, 2010 by Windpower Engineering
Filed under Fastening-Joining for Wind Power, Mechanical Components
Muskegon, MI – Reid Supply Company will be showcasing new products from innovative floor dryers to time-saving industrial clamps during the 2010 International Manufacturing Technology Show at the McCormick Place in Chicago, September 13th through the 18th.
Greg Palmer, Director of Marketing at Reid Supply, says the company is constantly improving their product category offerings to help their customers find the exact product that they need, without the need to do a lot of shopping around.
“IMTS allows us to showcase some of the literally tens-of-thousands of items available in our new 900 page catalog and thousands more on our website,” says Palmer. “Plus, show attendees get to pick our brains to help them solve problems with product ideas that they may not have considered.”
This year the company will be showing new products in the categories of Knobs, Handles and Hand Wheels; Clamps and Workholding; Fasteners and Hardware; Bearings and Power Transmission; Maintenance, Repair and Operations (MRO); and Safety.
“Each year we have a good selection of new products, like the Hurricone floor drying system, which combines a wet floor caution cone with a battery-powered floor dryer,” says Palmer.
Since 1948, Reid has supplied customers with both hard-to-find and everyday products to help them build their industrial business. Those customer’s who have shopped with company for decades know the value of this kind of longevity.

Not only will Reid Supply highlight new products at the annual IMTS show, they will also showcase their free CAD drawings of over 90% of their catalog products on their website at ReidSupply.com.
Reid Supply
www.ReidSupply.com
Lessons for using tools at height
August 3, 2010 by KRemington
Filed under Fastening-Joining for Wind Power
A structure or machine that requires fasteners also demands tools to maintain it properly. In the wind-power industry, the machine could be 300 feet in the air, which presents a variety of safety and efficiency considerations. Snap-on Industrial has worked in industries ranging from oil and gas production to manufacturing facility maintenance, and so has developed the concept of tools-at-height to address these considerations. In an environment where it’s simply unacceptable to drop anything, tools-at-height means essentially eliminating the potential for damage from a dropped tool.
The problem
A tool security and drop-prevention system improves site safety. In the wind industry, it’s easy to see how this is manifested when a worker drops a tool or a part of one. In the confined space of a nacelle or tower, a dropped ratchet at height can do more than merely startle workers below. It can cause severe injury or death. The reality is that four pounds of steel ricocheting off equipment or flooring after a 300-ft fall can create something akin to shrapnel. Dropping something that creates debris is as dangerous as actually hitting someone with an object from above.
And what of the time wasted when a worker forgets a tool and is forced to make “the walk of death?” Such unplanned trips down a ladder or slow-moving lift to pick up a wrench or screwdriver no one thought to bring up can quickly fill a day.
In addition, forgetting a tool in a critical area can cause considerable damage. The confined environment of a nacelle has many places where workers can lose or forget small tools – until an accident happens.

Took kits in bags designed for particular tasks make it easier for wind technicians to carry the appropriate equipment.
A solution
One of the key parts of the tools-at-height concept is a lanyard or tether. Tools built specifically to accommodate the tether let the design maintain its strength and structural integrity. The tether can also attach to a wrist or tool belt, depending on tool weight and application.
Other components include coiled, weld-less fittings that are built as an integral part of a wrench, rather than a modification. The design uses an anchor attachment “floating” across the length of the tool for easy use and without modifications that could compromise tool strength. Lock-on retention safety pins essentially bind a socket to a ratchet wrench, a significant improvement over the conventional ball-retention method.
Custom tool kits based on specific applications are another part of the tools-at-height program. Snap-on Industrial works with users in a variety of industries to create kits that contain all the tools necessary to complete the task at hand. This lets wind industry workers know they need no additional equipment and will not have to come back down the ladder after reaching the nacelle. Along with reducing tool-toting time, a dedicated kit provides a secure transportation method and acts as an extension of a comprehensive asset-management program. Shockproof or waterproof cases are available with etched foam tool-control packing. This way, every tool has its place, so users know immediately if one is missing. It reduces the likelihood of losing a tool in the confined space of a wind turbine, thereby protecting the investment.
Learning from other industries

The sliding yet captured ring allows tethering the wrench to a technician which practically eliminates the possibity of dropping the tool.
Foreign Material Exclusion (FME), a term originated by the nuclear industry, is a set of procedures that minimize the contamination of a system by foreign materials. For example, a tool that falls into a nuclear facility’s cooling tank must be removed. This is difficult in a radioactive environment, and the task can be just as difficult in other industries. The extra cost in dollars and safety concerns can be significant when a tool ends up where it shouldn’t be.
FME is a big issue in other segments of the power-generation industry as well. What would a misplaced socket do in a wind turbine? What are the cost considerations in shutting down a turbine, not to mention the maintenance necessary to bring it back on line?
The idea for tethered tools came from NASA requirements in the early 1980s, primarily for work done on satellites. These are extremely delicate designs that involve a lot of last-minute wrench turning at launch time. A socket dropped on a solar panel can create millions of dollars in damage. In the case of a satellite, it means sending the entire assembly back to the manufacturer for a repair that could have been prevented.
The offshore-oil industry has working conditions similar to those in the wind industry: confined spaces, workers
laboring one above another, a tool-intensive workplace, and potential to damage sensitive equipment. In this environment, a dropped tool can hit someone below or fall into the ocean. The problem with a tool lost to the ocean is that the rig could be 150 miles offshore with workers and equipment shuttled in by helicopter once a week. Oil rigs have little space for extra tools so dropping even one can significantly impact worker productivity.
The lanyard represents a low-tech component of any tools-at-height program. A good system includes a drop indicator that opens if the lanyard becomes overstressed. The indicator usually consists of excess strap material folded over on the lanyard and held in place by a threaded stitch. The open indicator tells the user the application has exceeded one limit and is approaching the tether’s capacity.
The socket is a challenging tool because it is relatively small and cannot be tethered. A solution is a pin in the socket to hold it in place and attach it to the ratchet. In turn, the lanyard attaches to the ratchet and to the worker’s wrist or tool belt.

Tool cases like this one let wind technicians quickly check that all tools are present and accounted for.
The wind-power industry has the advantage of learning tool security from older industries. The lanyard, socket pin, and tools tethered to the tool belt are components of a comprehensive tool-security program that enhances workplace safety and overall efficiency. Amateur modifications of existing tools are not an option in an environment where mistakes can lead to system failure or worker injury. Specialized tools with dedicated tethering systems are intended for use in close quarters or at height, supporting foreign material exclusion. The goal is superior site and worker safety, as well as increased productivity. WPE


