ThyssenKrupp

Keeping the pot boiling

Wherever boilers are employed for energy generation – be they in power plants or waste incinerators – the experts from ThyssenKrupp Xervon provide their high-quality inspection services.

GMVA Niederrhein (public-benefit waste incinerator) in Oberhausen, for example, is being supported by the Xervon Dortmund location during all the shutdowns in the current year. The routine inspection of boiler line 3 (waste throughput 25 t/h) was scheduled at the end of May. In need of cleaning were the downstream heating surfaces of the 4-pass boiler system and their electrostatic filter, which had been in operation for a year.
This is an absolutely typical task for the Germany-wide team of location manager Herbert Stremmer. His proficient inspection experts are fully conversant with boilers of all designs. Within a few working days, they reliably clean the in most cases skyscraper-tall, key components of the energy-generating plant – inclusive of prior scaffold erection performed by the associated Xervon department, if requested by the customer.

Two roughly 6 x 10 meter wide and 20 meter tall open passes in Oberhausen had to be cleaned in five days. These were joined by a third pass comprising six banks of tubes (each 6 meters long and about 4 meters wide), a fourth pass with three banks of tubes, and an electrostatic filter (30 x 30 x 20 meters). All these components underwent expert cleaning by Xervon's specialists, i.e. blast-cleaned with granulate and/or had their refractory linings processed with pneumatic hammers. A total of 14 employees – seven each during the early and late shifts – were assigned to these cleaning tasks. With a high-performance compressor (12 bar, 20 cubic meters) and a blast-cleaning and extractor system, the two practiced teams gradually removed all the contamination from the refractory linings and tube banks. As usual, three employees handled the blast-cleaning and two others organized continuous operation of the blasting boiler while the remaining two men operated the extractor system, safely collecting the contaminated abrasive and packing it in big bags for safe disposal.

The blast-cleaning work proper is a job for experienced power plant cleaners who are perturbed neither by the extreme heights nor by working in full protective gear with respirators in confined spaces. At the same time, a delicate touch is required. This is because although all the dirt has to be removed during the cleaning of the tube banks, walls and filter surfaces, the materials must not be damaged. This also applies to the electrostatic filter, on which the wires within the sheet metal blades have to be blasted clean.

The job in Oberhausen was accomplished without a hitch and on time – just as location manager Herbert Stremmer had assured the customer at the outset: "Even if the originally estimated volume of work is increased by unforeseen damage in the course of the project, we're able to quickly adapt to the new situation by managing our manpower and huge array of machinery accordingly. If necessary, the teams are bolstered by specialists from other projects or locations. And we respond just as flexibly in the event of short-term requests