D Series High Head Centrifugal Pump

The D series is a single-suction, multistage, sectional centrifugal pump used for clean water and liquids with physical and chemical properties similar to water, at temperatures not exceeding 80°C. Published coverage is 6.3-450 m³/h at heads of 49-650 m with motor ratings of 3-1120 kW, which puts it in high-head duty such as fire-fighting pressurisation, mountain water lifting, long-distance conveyance and small boiler feed. Head is built up by adding stages, so the same casing and hydraulic design covers a very wide pressure range without changing the footprint on site. The shaft seal is a combination of mechanical seal and packing seal using hard alloy seal rings, which raises the wear resistance of the sealing parts. The pump body is compact enough for outdoor placement, and a low-speed motor can be specified to smooth out running and reduce noise.

The supplier publishes one staged multistage table for the D, MD, DG and DF families. The rows below are the D-prefixed models taken from that table; head rises by one stage increment for each additional stage.

• Fire-fighting pressurisation: Supplies high-pressure water to fire main and deluge systems.
• Mountain and landscape water lifting: Raises water over large static heads for irrigation and landscaping.
• Long-distance conveyance: Overcomes pipeline friction on long water transmission runs.
• Small boiler feed: Feeds small industrial and heating boilers where high head is needed.
• High-rise building supply: Boosts water into tall buildings and elevated storage.
• Heating and hot/cold water circulation: Circulates water in heating, bathroom and process loops.

• Count the stages needed for the required head, since the D series builds pressure stage by stage at a fixed flow per casing size.
• Confirm the liquid stays inside the published 80°C limit and carries no solid particles, unless the build is changed for a special medium.
• Compare motor power with the duty shaft power; the published table gives the motor rating for each stage count.
• Choose the seal arrangement - mechanical, packing or a combination - against the liquid and the acceptable leakage.
• Decide whether a low-speed motor is wanted for quieter running, and confirm the outdoor installation conditions.