Broken screws a thing of the past

Louise Davis

Global water, energy and maintenance solutions provider, NCH Europe, has launched Cryo Ex-Tract, an extraction system designed to easily remove sunken or sheared off screws, studs and bolts with an irregular, work hardened, surface. Cryo Ex-Tract is designed for easy extraction within industries such as industrial manufacturing, food processing, oil and gas, waste water, marine, transport and automotive.

Threaded fasteners including screws, studs and bolts can often shear off as a result of corrosion, misalignment and poor application. This leaves the threaded section seized within parts of industrial plant equipment or machinery such as a flange, casing, cylinder head, sump and gearbox housing.

The new system features three parts. The first is Cryo Ex-Tract End Mills, a range of five end mills manufactured from Cryophase treated tungsten carbide. This process involves cryogenically freezing the product to harden it. With a speed rating between 17,000-22,000RPM the End Mills can machine metals with a hardness of Rockwell 50 (HRC) and machine bolts up to and including grade 12.9. A toothless outer circumference prevents the End Mills from causing damage to existing internal female threads.

The second part is Cryobit LH 135, a range of Cryophase treated drill bits with a left-handed flute and 135 degrees split-point geometry, designed for use on any standard drill in reverse action. The third, and final part, is a range of hardened steel, straight fluted tap-in extractors that can bite into materials of up to 58 HRC and are designed to fit all standard ratchet sizes.

"The problem with conventional extraction systems is that they struggle with work-hardened metal fasteners that shear off at an angle," explained Peter Crossen, VP of the Maintenance and Partsmaster Innovation Platform at NCH Europe. "The 180 degrees chisel-point drill bit used in these systems simply can't bite into the irregular surface of the fastener. Conventional extraction systems also use a right-handed drill bit in a clockwise motion, which only serves to tighten the fastener even further and the extractors are typically spiral fluted, making it difficult to obtain the correct alignment in the pilot hole.

"It was for these reasons we developed Cryo Ex-Tract. We've used Cryophase treatment to increase hardness and double the component life. The system offers three unique benefits. The end mills work to flatten the irregular surface, left-handed drill bits are used with a 135 degrees, self centering and fast starting split-point. Finally, tap-in straight-fluted extractors ensure correct alignment," concluded Peter Crossen.

Cryo Ex-Tract forms part of NCH Europe's cutting and extraction range, which also features X-Tractalloy, a manual metal arc-electrode extraction system designed for larger applications from M16-M25, and Mega Cut, a unique lubricant and cutting aid to improve the performance and life expectancy of the drill bit.

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