Best-efficiency point (BEP), the flowrate at which a pump operates at its highest or optimum efficiency for a specific impeller diameter, is a key consideration when assessing pump performance. While most pumps do not consistently operate at their exact BEP,…
Figure 1. During tightening, hydraulic pressure load within a bolt should be uniformly and accurately applied to avoid gasket damage and other issues that can create leakage Common knowledge dictates that planning ahead ensures effective results, regardless of the task…
New safety and environmental regulations, longer plant uptime and changes in maintenance practices have created new requirements across the chemical process industries (CPI). Among the plant equipment affected by these changes are control valves, since they are used in numerous…
Pressure variations resulting from the oscillatory flow patterns found in positive-displacement machinery, especially reciprocating compressors, are referred to as “pulsations.” Found in both liquid- and gas-handling systems, pulsations are a common phenomenon in the chemical processing industries (CPI). Operational problems…
There is a temptation that steam design engineers find difficult to resist — to put condensate from high-pressure (HP) steam mains directly into the low-pressure (LP), pumped condensate-return (CR) mains. After all, the CR main is so convenient — it…
Lubricants in rotating machines reduce friction and wear, dissipate heat, protect surfaces, keep out foreign contaminants and remove wear particles. Commonly used liquid lubricants fall into two main categories: mineral (petroleum-based) oils and synthetic oils. Mineral oils…
Good troubleshooting skills are invaluable in chemical engineering practice. While their value is clearly gleaned from the impact they have on plant performance, it is also a reflection of the intangible process of learning them. Last month, at the AIChE…
The massive buildup of new petrochemical capacity in the Middle East and Asia has been well documented, and its effect on future supply-demand much discussed. But a look at the average ages of plants in different regions in the years…
Water hammer — a high-pressure surge or wave created by the kinetic energy of the moving liquid — is not only a system issue, but primarily a safety concern. Understanding the nature and severity of water hammer in a…
A customized inspection and maintenance program will minimize operational and performance problems with glass-lined equipment Glass-lined steel equipment is used in a wide range of chemical processes that involve harsh chemicals, including the production of pharmaceuticals, specialty chemicals, agricultural products…