Reline Fired Heater – Pump casting
Background
Cape Refractory Industries (CRI) was commissioned to evaluate the feasibility of relining a fired heater on a petrochemical refinery with lightweight refractory castable, without necessitating the removal of the internal tubes. The client’s heater, originally lined with a duel lining medium-weight insulation refractory material, required repairs. However, the conventional reline process, which involves tube removal, was impractical due to its cost and the extended downtime it would incur.
Objective
The primary objective was to safely and effectively remove the existing dual refractory lining located behind the tubes, without causing damage to the tubes. The subsequent goal was to install a new anchoring system that would secure the insulation lining and support the new refractory material.
Plan of Action
CRI's strategy involved a detailed assessment followed by meticulous planning and execution. The plan encompassed the following phases:
Planning
Effective collaboration between CRI and the client was crucial to the success of the project was tasked with managing the turnkey project.
Demolition
Installation
The installation involved several key components:
- Anchoring System: Rapid Ark Stud Welding was the utilised to install anchors. RASW is and efficient very quick installation method that reduce installation time dramatically. RASW anchors are specifically designed for the installation to support the ceramic fibre insulation board lining against the shell.
- Specialised Steel Former: CRI designed and manufactured a custom steel former to maintain parallel spacing between the wall and tubes. This former was meticulously installed and levelled to ensure accurate casting.
Challenges
The pump casting method posed several challenges:
- Equipment Costs and Maintenance: The equipment required for pump casting is costly and necessitates regular maintenance.
- Only specific pumping equipment can be used for this installation.
- Blockages: A skilled team applying proven methods is paramount in order to prevent frequent blockages
- Casting Process: To address the challenges of refractory casting, CRI collaborated with a renowned refractory material manufacturer to implement a pumping method. This approach facilitated the rapid and efficient transfer of approximately 3.2m³ – 3.6m³ of material per section per day without using large teams, buckets and reduced wastage. The consistency and quality of the castable were closely monitored to ensure optimal results.
Throughout the project, comprehensive quality control documentation was compiled and provided to the client for their records.
Results
Despite the challenges, CRI’s team successfully completed the project in under six weeks. This efficient turnaround alleviated the client’s concerns about sourcing new tubes and the complexities of tube removal and reinstallation. The reline was executed within a contained area, followed by a controlled dry-out and cooling cycle. Upon final inspection, the unit was returned to production, continuing its operations seamlessly.
This case study demonstrates CRI's ability to innovate and execute complex refractory projects, ensuring minimal disruption and optimal performance for the client.