Newsroom - Mar 8, 2024

Webinar – The Latest Innovation in Fired Heater Convection Section Cleaning

tube tech robot on convection section tubes

We have hosted a webinar and Q&A session on March 7th, 2024, at 1 pm GMT, providing an in-depth exploration of the new system and its capabilities.


Watch the webinar recording





  1. How does it work?

Our bespoke cleaning robot is a compact remotely operated vehicle (ROV) placed on the top row of every convection coil to be cleaned (subject to height clearance between banks). The ROV travels along the length of the bank. The cleaning arm is computer controlled and can be of various lengths dependent on the pitch and depth of coil. The ROV arm slides down between the  (finned or studded) tubes. The ROV arm cleans deep between the tube rows. Due to the 5 to 10mm  proximity of the cleaning head  to the fouling ,the pressure easily removes the hardest type of fouling that can be found e.g.  cement, sulphur, and concrete like deposits.

  1. What cleaning medium do you use?

The robotic system uses hydro jetting technology (water only). It uses a low flow of water and only 100mm of high-pressure cleaning area, so the system is very precise.

Some plants request passivation of stainless-steel tubes before cleaning and supply us with 5% soda ash solution, which we are happy to accommodate.

  1. . What is the flow rate and pressure of the water jet?

The working pressure can reach 15,000 psi (1,000 bar). However, we usually operate at  10,000 psi (700 bar).

The flow rate of the jetting arm is 24-l/ min, and the flush bar is 67-l/min.

The fins in the convection section are steel, not aluminium so they are very strong and robust – the pressure and flow rate is generally not an issue from a material protection perspective.

  1. Will the debris and water harm the refractory and where does it go?

No. The debris falls with the water and is collected in a catchment area that is set up below the convection box. The water does not harm the refractory as it is not blasted or soaked with water; the cleaning head is kept away from the refractory. It may become damp but dries out very quickly.

There is also no need to protect the refractory in the convection section as it is castable or castable brick. The refractory that needs to be protected is in the radiant section. Therefore, a containment area is built below the convection section, so all effluent is collected and does not reach the burner floor. All water and debris is collected and can be disposed of responsibly.

  1. How does the cleaning rover reach each convection tube row?

The cleaning rover moves on the top of the bank and the patented lance system penetrates between the tube rows, oscillating as it moves and adjusting its angle to each bundle. It’s fully adjustable depending on the severity of fouling.

  1. Can the robot clean banks with intermediate tube supports?

ROV is designed to cross over tube supports up to 50-mm (2”) high above the top tube in the bank;

  1. How long will the robot clean a complete a convection section coil?

It depends on the size of the heater and the level of fouling.

For a project time estimation, submit your ‘as-built’ furnace drawings to our team at [email protected]

  1. Are there any disadvantages of the system vs traditional methods?

The rover system is far advanced in terms of the level of cleaning provided. The only downside is that we can’t clean online. We can debottleneck the convection section online with our Hot Convection Cleaning Service.

Chemical cleaning or dry ice can typically only reach 20-30% of the surface area. The rover system can clean more than 90%. Chemicals can also compound the fouling if the type is unknown and there are environmental, and health and safety concerns associated with chemical use.

  1. Will Robotic/ROV Technology damage fins?

No – Unless fins are severely corroded. If they are generally in good order, and made from ca 1 to 2mm steel plate, they can theoretically take a distributed load of 500 kg over 24-cm2. Our rover system weighs no more than 25kg.

  1. How to inspect Convection banks with a robot?

We provide audit and inspection via Robot/ROV-mounted cameras or video probes or digital camera, which is positioned to take images between the triangular pitch of tubes. When you start the unit, you’ll also see the stack temperature drop.

  1. What is the approximate price for cleaning?

Pricing is dependent on heater dimension, accessibility, fouling levels, site supplies etc. For this reason, all projects are quoted independently.

For a  quote, send us ‘as-built’ drawings to [email protected]

  1. How quickly can you mobilize?

We need a 90-day notice to book equipment and team. If the team has not been booked for another project, the mobilization will take five to ten days. Visa requirements should be taken into consideration for countries other than USA, UK and Schengen area.

  1. Are there any video clips showing the actual cleaning of the tubes by the system?

You can request an in-person or Microsoft Teams meeting with a local representative where we will present to you and your team and show you videos and references of many projects.

To arrange a meeting, contact [email protected] with your requirements.

  1. Have you done any projects in my area?

We have completed projects globally. Read our range of case studies to find out more or contact your local representative by submitting an enquiry via our contact form.

  1. What if there is no access doors to some ports or they are too small?

We build/increase access ports as a part of our Hot Access Creation Service.

  1. Can you debottleneck the convection section on the live heater, not waiting for a TAR?

We can debottleneck the convection section online with our Hot Convection Cleaning Service.

  1. My convection section has another problem – the gas temperature entering it is too high/too low.

Our Cetek coating often helps with the problem, increasing the efficiency of the radiant section.