Trends in wind fasteners
May 13, 2011 by Windpower Engineering
Filed under Fastening-Joining for Wind Power, Mechanical Components, Turbine Design
Wind turbines, like helicopters, are fatigue machines—always vibrating and working to loosen their fasteners. More vibration will come as engineers develop longer blades to capture more wind energy and towers reach higher to accommodate them. These increased vibration levels will loosen some tower fasteners. To prevent this, engineers are looking for better ways to measure tension (than torque) and prevent corrosion. Finally, fastening companies are becoming more wary of costs especially as they count toward total cost of ownership (TCO).
Torque control is a risky way to achieve consistent pretension in structural bolts. As Barnaby Myhrum, application engineer at Applied Bolting Technology, explains it all comes down to the k-factor, the relationship between the torque applied to a fastener assembly and the actual tension reached in the bolt.
K-factors range from 0.10 to 0.20. “Add in the variability of torque tools and you can bet that when using torque control to generate a precise load, actual bolt tensions will vary ± 40% or more,” Myhrum explains. He says crews can find a better tension indicator in the squirter direct tension indicator—a washer that tells when a target tension had been reached in a bolt, regardless of the applied torque. When the bumps on the washer compress sufficiently, bright colored silicone squirts from cavities under the bumps. The bump compression and squirt appearance are calibrated to a required tension. GL certifies that the devices for M36, M42, and M48 bolts will reach target tension ±10%.
Other construction trends deal with ways to keep bolts tight. VP of Disc-Lock International Greg White says a locking washer can eliminate fastening failure. “The device consists of two preassembled washer-shaped pieces that have inclined cams on one side with a series of radial ridges on the other. These cam sides are placed between the nut and joint material. The cam angle is greater than the bolt-thread-pitch angle so the interlocking cams and non-slip ridges of the washer jam to prevent the nut from loosening under vibration.”
Tension-control bolts are replacing some conventional high-strength friction-grip ones, says White, because they are quick and easy to install with a lightweight electric shear wrench. “Guaranteed tension and a visual inspection eliminates the likelihood of operator error and ensures engineers that connections are tightened according to specifications,” he says. Another perk of this bolting system is that it is easily removed and reused, which saves costs. Other types of secure bolts are not easily removed and must be burned or cut off destroying the bolt and requiring purchase of a new one. White says another way to trim costs is by using an electrically powered shear wrench that’s lighter than hydraulic wrenches. It requires one worker and improves safety. “The shear wrench uses two sockets that rotate in opposite directions, allowing the nut to turn while the bolt remains stationary,” he says. “The counter-force operation transfers no torque to the operator thereby reducing fatigue that can cause carpal tunnel syndrome.”
In addition to keeping bolts tight, operators must protect them against corrosion. This will become more important as turbines head offshore. Coatings, such as Magni 501 from the Magni Group Inc. helps keep nuts, bolts, screws, and other types of hardware from corroding. The silver coat is a replacement for zinc plating and trivalent passivation, and can be applied in dip/spin or spray methods.
The industry is also growing more concerned about total cost of ownership. John Grabner, president of Cardinal Fastener & Specialty Co., says procurement managers must ask themselves several questions when submitting a quote for safety-critical fasteners. “When erecting a $3 million turbine, safety-critical fasteners amount to less than 1% of the total cost,” he explains. “More than just price must go into a procurement decision. Taking quality, delivery, and service into consideration will help lower TCO.” If a fastener doesn’t meet high quality standards, projects may incur costs related to replacing the parts or eventually repairing the turbine, he says. Choosing a domestic source also affects TCO, because OEMs can purchase products and have them delivered quickly to sites for construction and fabrications. Waiting for deliveries from overseas suppliers may result in expedited air-freight charges, lost or misplaced goods, and or liquidated damages. Hence, the shorter the supply chain, the better.
WPE
Manufacturer of fasteners offers products in more stores
November 9, 2010 by Kathleen Zipp
Filed under Fastening-Joining for Wind Power, Mechanical Components
A manufacturer of fastening products will work to increase their presence at Fastenal stores. Offering a range of fastening equipment, Fastenal locations are well suited for carrying Disc-Lock International products. The company has appointed Greg Bolduc as Disc-Lock account manager to be in charge of sales and service to Fastenal.
“Bolduc brings over 20 years of industrial sales and management experience to our company,” says Alistair McKinlay, Chairman of Disc-Lock International. “Fastenal maintains over 2,300 store locations and Bolduc’s past experience, including managing the Fastenal account at a previous company, will be an asset to both DISC-LOCK and Fastenal as we increase our presence at their stores.”
Bolduc will be demonstrating DISC-LOCK products to the Fastenal stores with mini seminars. In addition, he will continue to offer Disc-Lock products in smaller quantities (rather than large case lots) via the Bolt ‘n Lock website www.boltnlock.com, giving customers quick access to the company’s product line.
Disc-Lock www.disc-lock.com
Fastener manufacturer sells in Copper State Bolt & Nut
November 1, 2010 by Kathleen Zipp
Filed under Fastening-Joining for Wind Power, Mechanical Components
A California-based manufacturer of fasteners will make their products more available by offering them through Copper State Bolt & Nut Company. DISC-LOCK International, along with the Safety Wheel Nut, announced a marketing distributorship and affiliation with the Phoenix-based supplier to sell their products in 21 locations throughout the Southwest.
Copper State Bolt & Nut Co. supports 21 locations in Arizona, Texas, Colorado, New Mexico and Nevada. The company offers products and services throughout the Southwest U.S. in support of mining, construction, steel fabrication, MRO, OEM, and utilities/municipal.
“Our distribution collaboration with Copper State Bolt & Nut is a great juncture as they will merchandise our products to their affiliations in mining, construction, steel fabrication, MRO, OEM, utilities, municipalities, and fluid sealing industries,” says Alistair McKinlay, Chairman of DISC-LOCK International. Founder and Chairman of Copper State Bolt & Nut Martin Calfee says the company is glad to be extending its inventory to meet customer’s needs.
“In every market which we operate, opportunities exist to service customers who are not typically provisioned by Copper State,” says Yates Hudson, President of Copper State Bolt & Nut. “DISC-LOCK fastening technology fits precisely into our company objective of capturing new fastener markets,” Yates added.
DISC-LOCK manufactures a range of safety fastening solutions for transportation, industry and the military including trucks, trailers, buses and wind turbines and towers. DISC-LOCK products include; Safety Wheel Nut, Vibration Proof Locking Nut, Truck Frame Fastening System, Rail Car Fastening System, Armor Fastening System, Shear Wrench, Tension Control Bolt, Hex Head Bolt and Locking Washers. Copper State Bolt & Nut Company is a supplier of fasteners, industrial and construction supplies, tools and tool repair, cutting tools and abrasives, and fluid sealing products.
Disc-lock www.disc-lock.com
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
High-strength latches
June 17, 2010 by Kathleen Zipp
Filed under Fastening-Joining for Wind Power
The new draw latches feature riveted mounting baseplates, that allow distributing loads over a large bearing area. Protex 43-3292, 43-4292, and 44-4292 latches are well suited for the industrial, earth-moving, and process equipment sectors.
44-4292
The fasteners are compatible with Protex 40 and 41 series latches. They come in stainless or zinc-plated mild steel, reaching tensile strengths of 2,000 and 2,500 with type 04-4292 catchplates. All models have a standard grip range adjustment of 20 mm, and seal using lock wire or self-retaining pins. Both models can be padlocked for added security, while the 44-4292 is fitted with a side-action catch that locks when the latch is closed. The 43-4292 and 44-4292 models have an optional 150-mm long eyebolt, which increases the grip range adjustment of each product to 60 mm.
43-4292
Protex Fasteners Ltd.
Tight or Not, This Bolt Tells
November 26, 2009 by Windpower Engineering
Filed under Fastening-Joining for Wind Power, Maintenance, Materials, Wind Safety
The VLI or Visual Load Indicator is a tension indicator built into the head of a bolt or stud. Reading the dial tells whether or not the bolt has reached its proper fastener load. If the bright yellow tension indicator stripe is hidden on the black face, clamp load remains assured within ±5%. If the yellow tension indicator stripe appears, the fastener needs maintenance. The advantages of VLI are that it gives maintenance personnel a quick visual tension check that can be performed at up to 30 feet away and greater distances with binoculars. VLI also provides indication of tension overload as well as under-load conditions. All fasteners are affected over time in service by temperature changes, joint relaxation, pressure fluctuations, and vibration. Adding this indicator to key wind-turbine fasteners significantly reduces scheduled time for maintenance and fixed costs while improving bolted joint safety and durability. The fasteners are approved by Germanischer Lloyd.
EGC Inc.
Egc-ent.com
