Let’s talk about Bellmouths
As we near the end of our series of flow control blogs, we turn to the Bellmouth and find that – as with so many of our highly technical products – it’s actually based on some much less high-tech, historical, everyday concepts. Imagine a bell, with a mouth, which can open and close as necessary and you’re pretty much there!
Hydrostatic Bellmouths (or sometimes referred to as Telescopic Bellmouths) are used in all areas for flow and level control, from changing the overflow levels in a water tank, to removing sludge from sewage treatment settling tanks – enabling these process to be automated, thus streamlining the treatment processes.
The shape of the Bellmouth cone is critical to ensure an even flow either into or out of the pipework to which the Bellmouth is attached, this shaped section can also reduce the exit head losses when used on pumped outlets.
There are 3 main components of a Hydrostatic Bellmouth:
- The operating equipment
- The inner pipe with bell shaped top
- The outer pipe
In its simplest terms, the operating equipment raises and lowers the inner pipe within the outer pipe, to regulate the flow of liquid in to or out of the top of the inner pipe. The outer pipe connects to a pipe flange at the base of the chamber and the total height of the Bellmouth is determined by the range of movement required, along with the top and bottom water levels.
IBS Engineered Products is a key provider of Bellmouths in the UK. We can provide hydrostatic Bellmouths in a range of sizes with varying features and material specifications, including:
- 100mm – 600mm diameter
- Manual or electrically actuated operation
- Inner pipes in stainless steel 1.4301/1.4304 (304/304L) or 1.4401/1.4404 (316/316L)
- Outer pipes in mild steel (painted) or stainless steel 1.4301/1.4304 (304/304L) or 1.4401/1.4404 (316/316L)
- Standard PN16 flange, other flanges available upon request
- Pillars in mild steel (painted or galvanised) or stainless steel 1.4301/1.4304 (304/304L) or 1.4401/1.4404 (316/316L)
- A2 or A4 fasteners
As well as these options, IBS’s expertise and unique approach to projects and customer satisfaction, means that specialised tailor-made solutions can be created for any client’s needs. One specific example is from the Snarrows Wastewater Treatment Works (WwTW), where IBS was tasked with the design and manufacture of a unit to replace a cast iron desludging Bellmouth. The problem was that the existing Bellmouth was cast into the floor of the desludging chamber, preventing the usual connection of the new product. IBS developed a special gland plate connection, enabling the new Bellmouth to be fixed directly to the concrete floor of the chamber, spanning the existing pipework connection. The full project case study for Snarrows WwTW is available on our website here.
Many flow control products are based on technology from hundreds of years ago; several are brand new, modern designs based on the latest technology. And interestingly, even more are actually a mixture of both. For further information about IBS’s Bellmouths, or any of our flow control products – whether old, new or a hybrid idea – give us a call!
