Document NembrDZQxzOgoy9EgObY7Xppw

r/ American Society of Heating and Ventilating Engineers Guide, 1934 the casing. The casing is lined with bright tin and coated with asphalturri. The pipe is supported on rollers carried in a bracket which fits into the casing. The lengths of casing are tightly fitted together with a male and female joint. This form of conduit is illustrated in Fig. 1 at A. The casing rests on a bed of crushed stone with tile drains laid below. The tile drains are of 4-in. field tile or vitrified sewer tile, laid with open joints. Filler Type: The pipes are supported on expansion rollers properly supported from the conduit or independent masonry base. The pipes are protected By a split-tile conduit, and the entire space between the pipes and the tile is filled with an insulating filler. Thus the pipes are nested and the insulation between them and the tile effectively prevents circulation of air. The conduit is placed on a bed of gravel or crushed rock from 4 to 6 in. thick, which is extended upward so as to come about 2 in. above the parting lines of the tile. A tile underdrain is placed beneath the conduit throughout the entire length and is. connected to sewers or to some other point of free discharge. At B and D in Fig. 1 are shown two forms of tile conduit of the filler type. Circular Tile or Cast-Iron Conduit: The pipes are carried on expansion rollers sup ported on a frame which rests entirely on the side shoulders of the base drain foundation. iuo.iTXyBuii.oaff Chapter 36--District Heating F ig . 2. Steam Service and M eter Connections w ith Cooling Radiato r Fig. 1. Construction Details of Conduits Commonly Used The pipes are protected by a sectional tile conduit, scored for splitting, or a cast-iron conduit, both being of the bell apd spigot type. . The conduit has a longitudinal side joint for cementing, after the upper half of conduit is in piace, so shaped that the cement is keyed in place while locking .the top and bottom half of the conduit together with a water-tight vertical side joint. The cast-iron conduit has special side locking clamps in addition to the vertical side joint. The entire space between the conduit and the pipes is filled with a water-proofed asbestos insulation. The conduit is supported on the base drain foundation, each section resting on two sections of the base drain, thus inter locking. The base drain is so shaped that it provides a cradle for.the conduit, resting solidly on the trench bottom and providing adequate drainage area immediately under the conduit. The underdrain is connected to sewers or some other point of free discharge. For tile conduit the base drain is vitrified salt glazed tile and for cast-iron conduit it is either extra heavy tile or cast-iron. A free internal drainage area is also provided.to carry away any water that may collect on the inside of the conduit from a leaky pipe or joint in the conduit. Broken stone is filled in around the base drain and up to the vertical side joint. The broken stone is covered with an asphalted filter cloth to prevent sand, etc., from sifting through the broken stone and clogging the drainage area of the base drain. The tile conduit is made in 2 ft lengths and the cast-iron conduit in 4 ft lengths, cast in 522 N. I