Coker Drum Replacement requires significant planning due to the unique specification, the turnaround time required, and the normal inclusion of Automatic Unheading Valves, such as DeltaValves.
Coke Drum Replacement Complications:
Coke Drum Specification.Although Coke Drum must meet ASME code, the consensus is that Coke Drum wall thickness, welding and manufacturing procedures, etc. must exceed ASME code requirements.Cases wherein thin walled Coke Drums have been utilized have resulted in short Coke Drum life.
Lift plan, project execution plan, and schedule to replace drum during turnaround.
Unique aspects include lay down space for both old and new drums, wind speed limitations, inclusion of Automatic Unheading Valves, and planning to remove and reinstall the drill gantry structure.
Safety is always a concern.
Automatic Unheading Valves are a safety item sought by most Refinery Operations.During Coke Drum replacement is the natural time to install them.However, the addition of Unheading Valves adds many additional challenges as discussed below.
Unheading Valves also require side inlet to the drums which add piping, Coke Drum modifications, and often platform and structure modifications.
DeltaValve and Zimmermann & Jansen both offer automatic unheading valves.The design of the valves is different but the safety aspects and time reduction benefits are similar.DeltaValve was first to be installed and has many installations.
Unique considerations when installing Automatic Unheading Valves:
Spacing and piping design. - The valves are large, requiring piping modifications to install them.Unheading Valves also require side entry to the Coke Drum cone.
Weight of unheading valves. - Structure has to evaluated consistent with seismic and civil requirements.
Instrumentation required. - Location for instrument and control valves.
Delivery. - Bidding, purchasing, contracting and manufacturing takes time.
Costs. - Installed costs are significant, especially when considering the additional instrumentation, platforms, piping modifications, drum modifications, etc.
Justification. - Safety and cycle time improvement justify costs.
Adams Project Managers, Inc. (APMI) 14162 W. 142nd Street, Olathe, Kansas, USA, 66062 Call:913-706-5238 Email: APMI.Jack@Gmail.com
Adams Project Managers, Inc. (APMI) 14162 W. 142nd Street, Olathe, Kansas, 66062 USA Call: 913-706-5238 Email: APMI.Jack@Gmail.com