Proactive seal reliability strategies: Maximising pharmaceutical uptime

For any industry, unplanned downtime is an everyday risk and business problem. But for the pharmaceutical industry, the financial consequences of each operational failure can amount to an existential threat for smaller operators.  

Industry data specialists IDS-INDATA estimate that U.K. and European manufacturers lost £80 billion due to downtime in 2025.   

That means a loss of up to £10 million every time equipment failure leads to an unexpected interruption. And that figure does not include the additional risk of non-compliance with GMP and MHRA regulatory requirements or the reputational risk of missed delivery windows.  

And the chances of failed batches, quality deviations and compromised sterility are increasing as pharmaceutical companies cope with the increasing pressures that modern production complexity places on rotating equipment reliability.  

New challenges include: 

Wherever they are based, pharmaceutical companies must also mitigate the day-to-day challenge of regulatory compliance, such as:  

Sealing the pressure – pharmaceutical equipment  

Recent technical product challenges and the well-established regulatory obligations put equipment under stress, and it is often the mechanical seal in any process that is subject to the most extreme pressures, temperatures and materials.  

If a non-contacting mechanical seal has been selected for the application, correctly fitted, used within the specification and managed sympathetically during testing Sterilise-in-Place (SIP) and Clean-in-Place (CIP) routines, process owners can expect a long working life. However, failures can and do occur. Equipment in these circumstances will often fail for one or a combination of three reasons: 

The life of the seal can also be dictated by the host equipment. For example, running a pump beyond the optimal efficiency point – outside the preferred or acceptable operating range – can adversely affect seal life. 

Another potential cause of premature seal failure is thermal shock, which can be triggered during SIP cycles, underlining the need to choose a seal specified, designed and selected appropriately for the application.  

Similarly, effective processes can prevent thermal shock during CIP and SIP by adjusting temperatures to preheat the seal before introducing steam and gradually lowering temperatures after sterilisation. 

While failure is inevitable, predicting the tipping point is difficult and, therefore, a challenge for those planning maintenance schedules. In the context of pharmaceutical processing, success means ‘business-as-usual’ while avoiding the technology failures that risk product contamination, environmental release and safety incidents.  

Mechanical seals face many challenges. They include: 

Demanding operating environments 

Water and utility management constraints 

Ageing assets and inconsistent maintenance practices 

Other factors influencing seal life and performance include deploying the incorrect seal selection for clean/sterile applications, and, by extension, thermal shock from SIP regimes; poor system design causing dry-running damage due to lack of monitoring. 

Condition monitoring (CM) or the lack thereof, does not cause, accelerate or prevent failures. Selected to target known failure modes, CM can provide early warning of unsatisfactory operating conditions and/or onset of failure to allow corrective actions to take place before unwanted consequences are experienced. 

With seal integrity crucial to processing success, seal selection and technical support are key to maximising uptime for manufacturers. John Crane brings more than 100 years of sealing success to the pharmaceutical industry and supports customers both with technologies and support systems that maintain uptime.  

Engineered for pharmaceutical – high reliability mechanical seals  

Vessel, mixer and agitator seals 

Type 5600 series  

These high-performance O-ring pusher seals are a truly universal cartridge seal. One seal family covers more applications to address the issue of diversity in pharmaceutical plants to simplify maintenance, reduce downtime, increase efficiency and lower costs.  

John Crane’s Type 5615, Type 5615Q, Type 5625 and Type 5625P cartridge seals are available with Alloy 20 or Alloy C-276 bellows, in either a rotating or stationary arrangement, with tangential inlet and outlet ports.  

Designed for consistent sealing performance and long life across varying operating conditions, the Type 5600 series is a strong performer in hygienic and clean-process applications, making it deployed globally. 

The heavy-duty Safeseal Type SB1 single-cartridge seal is versatile and suitable for applications using water, clean fluids, oil and solvents. Easy to install and maintain, the uncomplicated design supports advanced technical features.  

These include seal face holders installed using an innovative heat-shrink process for correct, distortion-free face alignment at all recommended temperatures.  

The Type SB1 seal is calibrated for metric units (DIN), the Type SB1A for imperial units (ANSI), the Type SB1B fits big box bore pumps, while the Type SB1B suits fit larger stuffing box diameters. 

Meanwhile, the double-balanced design of the dual-cartridge Type SB2 and Type SB2A seals suits popular pharmaceutical industry process equipment, including agitators.  

Meanwhile, the Type SAF double-acting cartridge seal supports liquid transfer in heavy equipment in process industries that involve solid particles and impurities. 

The Type SE1 is a customer-fitted (OEM standard) single mechanical seal matched to Sulzer APP and APT pump series.  

Meanwhile, the Type SE1C is dedicated to the Scan process pump, and the Type SE1F is fitted with a flush. All suit clean and lubricating fluids, including water and solvents. 

The John Crane JCS series is another Sulver-specific solution. The Safeseal JCS1 O-ring pusher seal is a rugged, pump-integrated single seal compatible with Sulzer AHLSTARUP and Andritz process pumps, while the Type JCS2 O-ring pusher seal is suited to more demanding conditions, and the JCS2A fits both Sulzer liquid ring pumps and Andritz ACP pumps. 

Looking beyond the seal 

While every pharmaceutical processing ecosystem is dependent on a reliable mechanical seal, selected to meet the specific demands of that industry, that is not the complete solution.  

In the second part of our blog, we look at additional options, including support systems, maintenance programmes and proactive digital monitoring solutions.  

Further reading