For centrifugal pumps, "installation" encompasses the arrangement of the pump set on site, together with all piping connections necessary for commissioning. The pump set must be installed so that all external forces and moments (see Pump nozzle load) are safely carried by the foundation, supports, frames, plates or by the piping.
The type of installation depends on the pump type and frequently on the application: installation on a foundation or without foundation, wet well or dry installation, indoor or outdoor installation.
Installation on a foundation
In the case of an installation on a foundation (see Pump foundation), it is necessary to distinguish between horizontal and vertical shaft pumps.
Established designs for centrifugal pumps installed horizontally are the back pull-out design and for drive ratings of up to 50 kW the closed-coupled design (see Close-coupled pump). With the exception of close-coupled pumps, horizontal pumps and drives are supplied mounted on common baseplates. In the case of large pump sets and pump sets with gear units or booster pumps, individual baseplates are used for the components.
These baseplates are placed on the foundation and the cavities between them are filled with grout, e.g. cement mortar. The foundation bolts should only be tightened after the grout has set. Grouting provides the baseplates with the rigidity needed to prevent undue deformation or warping under load (e. g. pipeline forces).
After grouting, the couplings of the various pump set components are aligned by placing shims under the feet of the machines. After adaptation and connection of the piping to the pump (avoiding transmission of any stresses or strains onto the pump), and after installation of the accessories (e. g. lubricating device, filter, lubricating oil pump, valve etc.) an alignment check completes the installation of the pump set.
A V-belt drive is often used for horizontally installed pumps with single-vane or diagonal impeller (see Impeller). A V-belt drive with solid pulleys is suitable for minimising surge pressures in the system.
Instead of a belt drive, it is also possible to employ a variable frequency electric motor. The use of standardised electric motors makes operation at any pump speed possible (see Rotational speed) and allows the pump's output to be easily matched to the required performance data at maximum impeller diameters. An optimal hydraulic selection of the waste water pump with regard to its efficiency and NPSH can therefore be guaranteed.
The installation of vertical pumps and drives roughly corresponds to that of horizontal pumps. However, there is no need to align the couplings if the pump and drive are connected to each other via a motor stool. In these cases, the pump set is mounted onto the foundation via a foot flange. The motor stool determines the drive's exact position.
Installation without foundation
Installation without a foundation is chosen if the weights of the pump sets to be installed and the anticipated loads by the piping are limited, if the pump must remain transportable, or if vibration dampening is to be provided to ensure that solid-borne noise is not transmitted to the floor.
Submersible motor pumps, most in-line pumps and glandless pumps (e. g. circulating pump) are installed without a foundation. Large units are sometimes supported via additional simple foundations. If this is not the case, baseplates must be designed which are rigid enough to keep deformation within acceptable limits.
Transportable pumps such as fire-fighting pumps or mobile pipeline pumps are attached directly, or via their baseplate, to the mobile frame (e. g. carriage or skid). This type of installation requires flexible piping.
Portable pumps (e.g. garden pumps, cellar/basement drainage or dewatering pumps) are designed as close-coupled pumps which require no coupling alignment. They require no foundation as they are always small pumps attached to flexible hoses and not to a fixed piping. The motor housing and pump casing are designed for placing them on any even and firm surface.
Installation on a baseplate without foundation is sometimes specified for acid pumps to enable the straightforward removal of aggressive leakage fluids from underneath the baseplate. Such baseplates must be designed to be rigid enough to keep deformation within acceptable limits.
Wet well installation
An installation is termed wet well if the outside of the pump casing is in contact with the fluid handled. The advantage of wet well installation is that the installation and structural building costs are lower. The pump is submerged directly in the fluid handled, e.g. in the case of submersible pumps (see Deep-well turbine pump), submersible motor pumps or most tubular casing pumps. The installation types of
tubular casing pumps are further subdivided into those where the weights of the pump and the motor are carried either by a common floor level or by different floor levels of the structure and whether the discharge line can be installed either above or below the floor level of the pump sump.
If the pump casing remains dry on the outside, the pump is said to be dry-installed. The advantage of this installation is the fact that the pump room is accessible, which allows regular outside pump inspection (e. g. at the shaft seal) and the installation of other machinery.
This applies to most vertical marine pumps, whether pedestal-mounted (with the pump foot attached to a steel frame on the engine room floor, and with the pump casing and motor housing connected to one another by a motor stool) or bulkhead-mounted (the motor stool is attached to a bulkhead of the engine room).
Dry installation is also adopted for volute casing pumps used in other pump applications, e.g. in the petrochemical industry, waste water and sewage pumping (see Waste water pump), and for some tubular casing pumps.
The installation of a pump set with no protective building or roof is referred to as outdoor installation. General requirements for outdoor installation do not exist as the conditions depend very much on the place of installation.