TPT January 2007

A utomated S ystems for H andling, B undling & P ackaging

Diabolo conveyance systems: essential to the art of pipe blasting

Agtos GmbH, Germany, a surface preparation specialist, is geared towards providing application specific blasting solutions, based on an advanced plant concept from handling to transportation. The company have supplied such blasting technology to Calanbau GmbH, a specialist in fire protection systems. Calanbau offers solutions from the conventional sprinkler system to special extinguisher systems, with products including sprinkler units, spray extinguishing systems, foam extinguishing systems, argon and CO 2 extinguishing systems, and fire alarm and hydrant systems. Two blast units enable Calanbau to automatically process pipes of different diameters. For example, with pipes used in sprinkler

installations – which have diameters ranging from 114-210mm – external cleaning is essential prior to welding. In a combination of air and wheel blasting, the goal of blasting is workpiece hardening, following which no abrasive grains can be left inside the pipe. Pipes come from the production area and arrive in unsorted bundles at the blast unit (ie pipes with different diameters from 33-219mm).

› Calanbau specialises in fire protection systems

The pipes are automatically separated and placed, irrespective of their diameter, by a star wheel on a Diabolo conveyor. The rollers are positioned diagonally to the direction of travel, and the pipes are transported forward at an infinitely adjustable speed (5-17m/min), and also placed in rotation about their own axis. A switching threshold is installed before the entry vestibule of the blast cabin and this threshold activates an impulse as a pipe passes. Abrasive is immediately fed to the operational high-performance turbines, and this starts the blasting process. The pipes are uniformly cleaned from the outside. This ensures that abrasive is fed to the turbines only when a workpiece is in the machine, which limits wear and tear. Because of the abrasive effect of the blast media, the blast cabin, which is made of wear-resistant steel, is also protected by exchangeable anti-wear plates. Once blasting is complete, the processed pipe is transported into the exit vestibule, where it is automatically lifted until it reaches the ideal position in front of the blow-off nozzle. During this time, the next pipe is already being blasted. The sidewalls of the exit vestibule fold upwards and release the blasted and blown-off pipe, which then

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J ANUARY /F EBRUARY 2007