BOILER SHOP In later years machinery has figured largely in boiler construction, and the Swindon Boiler shop is thoroughly and efficiently equipped in this direction. Worthy of notice is the large hydraulic Flanging press which works at a pressure of 750 pounds to the square inch. The flanging of cold copper plates is carried out in this shop, which was the first to introduce that system. Electric machines are gradually replacing compressed air machines in this shop. Boiler plates are cut out and edges shaped by the oxy-coal gas process There is a Boiler Testing Plant by means of which all boilers are tested, first by hydraulic power and then under steam at high pressure, supplied from a master boiler, so that fires are unnecessary in the fireboxes of the boilers tested. This method permits of careful examination being made of boiler and firebox while under steam pressure.