Sanitary-Engineering Facilities, Construction and Installation of

the construction and installation of heating, ventilation, heat-supply, gas-supply, hot-water-supply, water-supply, and sewerage systems for buildings. A distinction is made between outside and inside work.

Outside work includes the outdoor laying of sewers and of mains and pipes for the supply of heat, gas, and water. It also includes the construction of boiler plants, gas distribution stations, and central structures for water-supply and sewage-collection systems—such as water intake works, pumping stations, water towers, and settling reservoirs. In the USSR, expenditures for such work constitute approximately 15 percent of the capital investment for present-day industrial, housing, and civil construction. Outside mains and pipes can be laid above or below ground. Underground laying involves earthwork performed by excavating and road-building machinery. Underground laying takes place in several steps: sections, or lengths, of pipe are prepared on the surface; the sections are lowered to the prepared base of the trench by means of truck cranes or winches; after being straightened, the sections are welded together; field joints (sockets) are caulked; and the line is subjected to hydraulic or pneumatic testing. It is very advantageous, especially in urban areas, to place mains for different purposes together in a single underground tunnel. Above-ground lines rest on metal or reinforced-concrete supports and are built primarily on the grounds of industrial enterprises.

The industrialization of pipe laying (seeINDUSTRIALIZATION OF CONSTRUCTION) is based on the preliminary preparation of the sections—including the application of corrosion-resisting and heat-insulating coatings—at a centralized production base and the subsequent installation of the sections at the site. In the case of very long lines, for example, gas pipelines, the preparatory work is done at mobile workshops.

Inside work includes the installation of parts and assemblies of sanitary-engineering facilities in buildings and structures. Such work accounts for approximately 10 percent of the total expenditures on the construction of a building. Installation is usually done by the industrialized method: all preparatory operations—such as the consolidation of assemblies and parts for installation and the completion of systems—are done at installation plants or at central preparatory workshops, where production processes are fully mechanized and automated.

In total prefabricated construction, some sanitary-engineering facilities are built into the structural elements of the building (seePANEL HEATING). The level of industrialization of the installation of sanitary-engineering facilities is considerably increased by the use of factory-made modular elements called sanitary-engineering modules, which are made of such materials as concrete, cement plaster, and asbestos cement. These modules are delivered to the construction site with sanitary fixtures and piping already installed and the interior finishing entirely completed. After the modules are installed, all that remains to be done is the connection of the pipes floor by floor.

Installation and assembly operations at the site involve primarily butt joints. This work is done by hand tools or power tools, such as pipe wrenches, spanners, electric nut drivers, and screwdrivers for wood screws. Ventilation equipment, air ducts, and mains are installed in industrial buildings by means of truck cranes, truck hydraulic hoists, and forklifts equipped with installation platforms.

To complete the inside work, the operating efficiency of the sanitary-engineering facilities is adjusted and checked.