What is a Submersible Pump?

1. Home
2. Pump Station FAQs
3. What is a Submersible Pump?

A submersible pump is a mechanical & electrical piece of equipment which can be completely submerged in water or medium, used to transfer the same liquid from one location to another via a common connecting discharge pipe.

The pump would be electrically rated to IP68 and generally either 110v (portable site units), 230v (domestic/commercial units) or 415v (industrial units).

The pump has the electric motor mounted directed on the pump casing and drives an impellor. There are various different impellor arrangements to suit flow / head characteristics, sewage or drainage water applications and type of application, common ones are:

Channel Impellor (single or multiple) – More efficient, so higher flow and heads achievable from same size motor than vortex. Sometimes lower solids handling or slighter risk of blocking. Better suited to surface water applications.

Vortex impellor – Less Efficient. Generally better solids handling capabilities, lower risk of blocking, so better suited to foul sewage applications.

Macerator Type – Greater efficiency, used on high pressure sewage systems, where the distance to pump is very great and/or existing pipework is small bore i.e 40-50mm. The pump contains an intergal grinder which shreds sewage water and faecal matter to enable it to be pumped in smaller bore pipelines.

Pumps can be either:

Heavy duty construction - all cast iron and/or stainless steel i.e housing estate, commercial hotel, restaurant or school etc

Light duty construction – Plastic or polymer, pressed stainless steel, cast iron/stainless i.e single domestic sewage or drainage use.

Pumps can be free-standing with cast moulded feet for stand-alone use within tank, chamber, lightwell or manhole or provided with optional guide-rail pedestal kit which has to be installed within tank and pumps pulled up and down using lifting chains on guide pipes. The later is used more commonly on medium / large applications or where depth of tank may cause unsafe maintenance procedures.

Pump(s) will be selected to suit the following criteria:

1. Heavy duty or light duty construction depending of application, as above,
2. Type of application – Foul sewage or surface drainage,
3. Solids handling capacity to suit size of foul / sewage application – Generally the larger the better i.e 50mm, 60mm, 75mm, 100mm soft solids handling, to minimise risk of blockages within pump casing.
4. Flow rate - depending on type / size of application, water authority consent to pump to their drain / sewer, if a requirement.
5. Estimated pump head – normally in ‘metres head’ – calculated from a combination of static head (invert level to sewer invert) and frictional head or losses in discharge pipework from pumpset(s).
6. Power supply available, 230v 1ph or 415v 3ph.