What are pipes made of

Stoneware pipes have been used since antiquity and, because of their excellent resistance to corrosive action, they are still widely used for nonpressure drainage purposes in diameters up to 40 in. (1000 mm).

Clay is ground to a powder and brought to a plastic state with water and other additives. It is then passed through a vacuum chamber to remove trapped air, and fed into extruders in which the pipe is formed. The extruded pipes are trimmed and dried, and then passed into kilns in which the temperature is raised to about 2000° F (1100° C) to cause fusion of the clay particles, or vitrification. Salt is sometimes added to produce glazed surfaces.

How to fix cracks in concrete floors

Concrete floors that are badly cracked may be repaired by topping the existing floor with a 2-inch layer of 1:2:4 mix concrete. This should be reinforced by lightweight steel-wire mesh, not lighter than No. 14 gauge, placed in the middle of the new layer.  To prevent cracking, the floor should be kept moist for a period of not less than 3 days.

Immediately before new concrete is poured, dry floors should be roughened, cleaned, and wetted and cement-sand grout (1 part cement to 2 parts sand by volume) scrubbed in to form a bond. If the old floor has been penetrated by seepage, either a bituminous coating or membrane waterproofing treatment should be applied to the surface of the old floor before the new concrete topping is placed.

How to use a add on air conditioner unit

This was designed especially for adding cooling to an existing forced-air heating system. As shown on page 39, a cooling-coil section is put above the heater and pipe-connected to the cooling compressor, which is usually located outside.

Refrigerant is pumped to and from the cooling coil section is put above the heater and blower works the year round. In summer, the house air is pulled through the furnace (which is then inoperative), blown through the add-on cooler for air conditioning and distributed through the existing ducts.