II. MANUFACTURING PROCESS
2.1. Manufacturing the housing (spiral)
The housing has a spiral form, and is manufactured in accordance with the
construction plans: Plans 01, 01-1 and 01-2.
A. Materials
The material employed to produce the housing are as follows:
• Steel sheeting. The steel sheeting used to construct the spiral and
suction tube is 1/8" thickness (equivalent to 3 mm), of heat-laminated
commercial quality. In this case ADC-C manufactured by Siderperú,
equivalent to ASTM A569. The sheet dimensions are 1.20m x 2.40m.
Electrically cut and welded steel sheeting is being used in the manufacture
of the housing and also of the suction tube, although they can be
manufactured using other methods, such as casting. Nonetheless, a prior
analysis of costs is required taking into consideration the location of
manufacture, series manufacture or other aspects considered significant.
• Oxygen and acetylene. The steel plates are oxygas cut, mainly using
oxygen and acetylene, although propane gas could be used in place of
acetylene.
• Electrodes. The electrodes used to weld the housing parts together are:
E6011 for penetration, Cellocord AP/P (Oerlikon) or similar, and E6013
for finishing: Overcord F/M (Oerlikon) or similar
• Paintwork. A base coat of anticorrosive paint is applied (zincromat), with
a finishing coat of vinyl or other metal paint.
• Other: Grinder discs, abrasive paper with a range of grit grades (60, 100,
120, 140, 240), vinyl thinners and plastic putty.
B. Method
The process of manufacturing the housing and suction tube includes marking
and cutting the materials (oxygas cutting) and the paint finish, as well of
course as the process of welding the parts or segments together.