IN Brief:
- Four pump applications reduced sealing water consumption from 8–12 litres/minute to approximately 1–2 litres/minute each.
- John Crane calculates savings above 6.2 million litres across a continuously operated 180-day sugar-production campaign.
- The supplier reports no seal failures on the four converted applications since 2019, compared with previous three-to-four-month failure intervals.
John Crane says a mechanical-seal retrofit across four pumps at a German sugar factory has reduced sealing water consumption by approximately 80%, cutting calculated water use by more than 6.2 million litres during a six-month production campaign.
Water consumption fell from 8–12 litres per minute to approximately 1–2 litres per minute on each converted application. With all four pumps operating continuously, the company calculates a minimum saving of 34,560 litres every 24 hours and more than 240,000 litres over seven days.
Extended across a 180-day sugar campaign, the stated minimum daily figure equates to 6,220,800 litres. The arithmetic therefore supports John Crane’s claim that the converted applications save more than 6.2 million litres during a full campaign.
Sugar factories operate under unusual maintenance constraints because seasonal processing can require equipment to run continuously for several months while harvested crop is available. An unscheduled pump or seal intervention during that period risks interrupting a process that has limited flexibility to defer throughput until later in the year.
The unnamed German producer had been experiencing mechanical-seal failures every three to four months before the retrofit. John Crane attributes the failures to high heat generation, poor lubrication, and abrasive and crystallising process media.
Several applications also consumed substantial quantities of water for seal cooling and lubrication. The customer’s stated objectives were therefore to improve mean time between repair while reducing utility demand rather than pursuing water reduction independently of equipment reliability.
The programme covers four pumps handling thin juice, thick juice, and recirculation or distillation streams. Operating conditions range from 80°C to 133°C and pressures from 1 to 4 bar, with the pumps running at 960rpm.
Those differences required separate engineering decisions for the individual applications. John Crane measured the installation space available on the existing pumps and selected Type 587, Type 5620, and SB2 Upstream Pumping seal configurations according to the process and support arrangement.
The installations include 65mm and 95mm SB2 USP designs, with API Plan 52 or John Crane SafeUnit SFD barrier-fluid support where required. The retrofit allowed the plant to retain the existing pumps rather than replacing the complete rotating assets.
That matters commercially because a seal problem does not necessarily justify changing the pump itself. Replacing a complete machine can extend a maintenance project into pipework, foundations, drives, electrical work, and recommissioning even where the underlying pump remains suitable for the process.
A seal retrofit provides another route, provided the replacement arrangement fits the available equipment and can tolerate the actual temperature, pressure, speed, and process fluid. In this case, the varying conditions across the four applications prevented the supplier from using a single identical configuration throughout.
The conversion programme was also introduced progressively rather than across all four pumps at once. Planning and preparation for the first installations took approximately a year, and John Crane says conversion work began around seven years ago.
That phased approach allowed the customer to observe operating performance before extending the technology to further applications. The supplier reports that all four converted pumps have operated without a seal failure since 2019.
Before conversion, average reported seal life was three to four months. The company now describes service life as several years, giving the case a maintenance consequence alongside the water saving.
The figures are significant because sealing water is consumed continuously while the pumps are operating. A reduction measured in litres per minute becomes much larger when multiplied by four machines running 24 hours a day throughout a 180-day campaign.
The project also separates water efficiency from reduced production. The pumps continue operating through the campaign; the saving results from lower water demand at the sealing arrangement rather than fewer operating hours or reduced sugar throughput.
That makes the case relevant to wider process-plant efficiency work. Utilities consumed by pumps, seals, cleaning equipment, cooling systems, and other ancillary assets can be less visible than the water or energy used by the main process, despite accumulating continuously across long production runs.
John Crane says the customer is considering further conversions. The 80% figure cannot simply be applied to other pumps because water use and sealing requirements will depend on each application’s existing arrangement and process conditions.
The supplier has not identified the German sugar producer, and the published case is based on John Crane’s own operating figures rather than an independently released customer dataset. The multi-year operating history nevertheless gives the retrofit a longer evidence period than a short demonstration or single-campaign trial.
Further conversions will show how much of the reported water and reliability performance can be reproduced across the remainder of the plant. On the four applications already converted, the measurable result is a reduction from 8–12 litres per minute to around 1–2 litres per minute per pump, alongside the supplier’s report of no seal failures since 2019.
