Torque-free fasteners shrink
Smaller isn't always better, but it can be more versatile. Consider, for example, the recently downsized Huck Spin fastener. In the past, these fasteners from Huck International Inc. (Waco, TX) had a minimum diameter of 1/2 inch and were aimed at heavy-duty commercial transport applications. "They're used in 75% of new truck construction," notes Jim Hutchison, Huck's business development manager. The new small-diameter Huck Spins come in 1/4-, 5/16-, and 3/8-inch sizes and cover a clamp-force range from 1,500 to 8,000 lbs. They're intended for use in high-vibration machinery, durable goods, recreational marine products, and general manufacturing applications. Smaller metric sizes are also in the works.
Available for nearly ten years, Huck Spin fasteners don't rely on torque. Instead, they work by swaging the fastener's collar in place on a pin that has been stretched by Huck's installation tool. According to Hutchison, Huck Spin fasteners install quickly—because torque takes time. They don't function by fracturing the bolt, so they leave no pintail waste or fracture surfaces. And Huck Spins don't suffer from the friction effects that make torque-bolt tensioning "a guess at best," Hutchison says, adding that the derived tension of Huck Spins varies by±2% rather than the±40% of torque bolts.
Besides their relatively diminuitive size, the new fasteners have another important feature: "The collars swage on at half the force of conventional lock bolts," says Hutchison. The downsizing has let Huck offer the collars and pins in a wider variety of softer materials. In addition to the Grade A steel of the original Huck Spin, the smaller models come in all carbon steels, including Grades 2, 5, and 8. The company also offers aluminum and stainless Huck Spins for use in corrosive environments.
Huck International Inc., 8001 Imperial Dr., Waco, TX 76714; FAX: (800)798-4825; www.huck.com
Resbond™907GF 2300F adhesive and sealant is formulated to seal exhaust ducts against corrosive chemicals and high heat. It cures in 4-12 hours after application (can be accelerated with mild heat) to form a hard ceramic with good resistance to chemicals, solvents, electricity, oxidizing, and reducing atmospheres. Bondable materials include metals, glass, ceramics, ceramic tapes, iron, and instrumentation. Applications include sealing or repairing exhaust systems, gas turbines, stacks, flues, heating equipment, pipes, and diesel engines.
Cotronics Corp., 3379 Shore Pkwy., Brooklyn, NY 11235; FAX (718) 646-3028; www.cotronics.com.
TRA-CAST 243S01 is a clear, liquid material that cures in thick sections to a "lens-like" appearance when exposed to ultraviolet light. Because of its rigidity, it is recommended for the coating of a range of products, from nameplates to plastic and metal automotive parts. The non-yellowing formula offers low shrinkage during cure and high durability thereafter. With a 200-W/inch medium-pressure mercury vapor lamp, it will cure at 5-10 ft/min.
Tra-Con Inc., 45 Wiggins Ave., Bedford, MA 01730; FAX (781) 275-9249; www.tra-con.com.
EP33 is a room-temperature curing adhesive for high-temperature bonding applications. It has an operating temperature range of -60 to 450F and produces tough, durable, high-strength bonds, which are resistant to thermal cycling and chemicals. Adhesion to metals, glass, ceramics, wood, vulcanized rubbers, and most plastics is offered. The hardened adhesive is an electrical insulator. It is 100% reactive and does not contain any diluents or solvents. It is available in 1/2-pint, pint, quart, gallon, 5-gallon, and drum kits.
Master Bond Inc., 154 Hobart St., Hackensack, NJ 07601; FAX (201) 343-2132; www.masterbond.com.