The delayed coking unit is potentially one of the most profitable operations at any refinery. It is also a dependency for plant-wide downstream operations. Valves must handle a range of gases, liquids and solids at varying pressures and temperatures: Reliability is not optional.
Coke drum isolation, 4-way switch and overhead vapor valves all play performance and safety-critical roles in the coking process. So do the support valves around the coke drum. In either case, poorly designed valves will quickly allow heavy residuum to creep into ball/seat or stem areas causing a valve seizure, downtime and unsafe working conditions.
The extreme heat and potential volatility of the thermal cracking process make coking a potentially dangerous application. The escape of process medium must be prevented to avoid potentially lethal situations. These safety considerations, in addition to increasing uptime requirements and yield goals demand exceptional valve technology and performance.
Coke drum isolation, 4-way switch and overhead vapor valves typically experience the most severe conditions and are the focus of the greatest scrutiny within the process. Valmet's engineers have meticulously developed valves to tackle the extreme conditions these valves experience. For example, seat back cavities are designed to prevent residuum from entering in the first place and are more easily purged. Also two body purge ports are used instead of one to further prevent residuum accumulation in the valve.
Valmet has gone one step further by applying the innovations and technologies developed for the severe-service valves to the ancillary process valves also likely to experience similar problems associated with coke residue.
The reliability offered by Valmet's valves helps refineries to run more efficiently and meet yield targets. They also help to support overall system uptime and reduce maintenance costs and the frustration that comes with poorly performing valves.
Valmet brings over 25 years of delayed coking process experience in designing and building valves and assemblies. This experience and expertise results in innovative technologies proven to lengthen run-times and reduce costs.
Improving availability with field proven reliability and advanced diagnostics