Figure 3-47. - An oxygas welding outfit.
Being a liquid, MAPP is obtained by the pound, rather than by the cubic foot, as with acetylene. One 70-pound cylinder of MAPP gas does the work of more than six and one-half 225-cubic-foot acetylene cylinders. This is a ratio of 70 pounds of MAPP gas to about 1,450 cubic feet of acetylene.
Total weight for the 70-pound MAPP cylinder, which is the same physical size of a 225-cubic-foot acetylene cylinder, is 120 pounds when full.
MAPP cylinders contain only liquid fuel. There is no cylinder packing of acetone to impair fuel withdrawal. For heavy-use situations, a MAPP cylinder delivers more than twice as much gas as an acetylene cylinder for longer periods of time. The entire contents of a MAPP cylinder can be used, since there is no acetone that could be drawn into the regulators or the torch. As the gas burns with oxygen, it produces a flame temperature of 5300F (2927C) and equals or exceeds the performance of acetylene for
Figure 3-48. - Auxiliary equipment.Continue Reading