Custom Scraper Pigs Deliver Efficient Decoke Without Costly Modifications

When a major refinery faced a significant coke build-up in the crude charge heater of its unit, standard decoking solutions came with an expensive caveat – cutting out the existing plug headers and replacing them with return bends to allow pig passage. Thanks to years of research and development, we were able to offer a smarter approach.

The Challenge

The refinery’s crude charge heater consisted of a vertical radiant section and a horizontal convection section, with tube sizes of 6” and 8”. In the radiant section, plug headers presented a particular challenge; the header throats were reduced by ¾” in the 8” tubes and 1¼” in the 6” tubes. Other decoking vendors proposed cutting and replacing these plug headers, citing their standard pigs’ inability to navigate the reduced dimensions.

However, this modification would result in additional downtime and considerable costs – both of which the client wanted to avoid.

Cokebusters’ Solution

We proposed a bespoke solution, supplying custom-engineered scraper pigs specifically designed to compress through the plug headers while retaining enough hardness to effectively remove coke deposits. Unlike solid-bodied or soft-core pigs, Cokebusters’ patented scraper pigs are manufactured with a laminated construction, providing an optimal balance of strength, durability and flexibility.

Produced at our UK Technology Centre, each pig is crafted through multiple casting processes, ensuring tight quality control and the ability to adapt designs for unique client challenges.

Execution & Results

Cokebusters’ decoking team deployed these bespoke pigs to clean the heater without any need for pipe modifications. Upon completion, the refinery conducted radiographic inspections of the tubes, which confirmed successful coke removal across nearly all passes. Only two tubes showed minor residual patches.

A subsequent flow test revealed a 22% improvement in heater performance, validating the effectiveness of the custom pigs and the cleaning process.

Conclusion

This case study demonstrates how Cokebusters’ ability to design and manufacture custom pigs in-house allows for efficient cleaning of challenging heater configurations without the need for costly mechanical alterations. By eliminating unnecessary downtime and providing a tailored solution, Cokebusters once again reinforced its reputation as an innovative service provider in mechanical pigging and fired heater maintenance.

Clients are always welcome to witness pig manufacturing and testing at Cokebusters’ in-house test loop, ensuring transparency and confidence in our custom solutions.

Looking for a smarter decoking solution?
Cokebusters’ bespoke scraper pigs are designed to navigate complex heater configurations without costly modifications. Contact our team to discuss how we can optimise your next turnaround.