Designing for zero leakage
Article Abstract:
Many developments have been made in rotating mechanical seals to reduce leackage. Plant leakage in the US exceeds 349,000 t per year, mainly due to valves and pumps. A pump with an adjusted gland packing is designed to leak annually as much as 4,745 lt of product. A single mechanial seal can control emissions to under 1,000 ppmv. Double seals consist of two seals and a barrier fluid, and allow zero emissions of product into the atmosphere. Ferrofluid seals work together with mechanical seals, which seal the process liquid. The ferrofluid seal acts as a barrier for volatile emissions. A spring energised seal for sealing valve stems also has secondary seals, which are energised by the force on the first seal. Tandem seals involve two seals, to prevent a butter fluid from contaminating another fluid. Causes of leakages are also presented.
Publication Name: Eureka
Subject: Engineering and manufacturing industries
ISSN: 0261-2097
Year: 1992
User Contributions:
Comment about this article or add new information about this topic:
Reducing friction is just the start
Article Abstract:
The correct choice of grease, oil or zero lubrication for industrial rolling bearings depends on operating temperature, speed and conditions. The lubricant must cool the components and reduce friction and corrosion. Grease lubrication is suitable for normal temperature and speed. Oil may be more appropriate at greater speeds and temperature or if oil lubricates other components. Compressed air mists or jets of oil may be necessary at high speeds. However, in food and pharmaceutical industries problems of contamination may necessitate zero lubrication.
Publication Name: Eureka
Subject: Engineering and manufacturing industries
ISSN: 0261-2097
Year: 1992
User Contributions:
Comment about this article or add new information about this topic:
'Thinking' bearings just round the corner
Article Abstract:
'Intelligent' bearings, recently introduced for automotive uses, give advanced warnings of wear on a bearing. The new bearings do not undertake self-diagnosis, but send information about the wheel to a brake management system. Premature failure of bearings can be dangerous. There will hopefully continue to be miniaturised sensor systems, until bearings are developed to monitor their own temperature, acceleration, load and velocity levels.
Publication Name: Eureka
Subject: Engineering and manufacturing industries
ISSN: 0261-2097
Year: 1992
User Contributions:
Comment about this article or add new information about this topic:
- Abstracts: Fusion bonding grows new honeycombs. 'Shrink bonding' makes joints stronger. Software models seal's future
- Abstracts: Are you listening? Implementing Deming's fourth point. Performance appraisals and Deming: a misunderstanding?
- Abstracts: Keypads take on toughest conditions. Short circuit damps stepper oscillations. Hydraulic leaks stemmed at source: soft seal technology is playing a key role in the development of totally leak-free hydraulic systems
- Abstracts: Paint overspray fed back into gun. Polymer friction pads can slip for years. Lateral thought cuts PTFE costs