rb bertomeu, S.L.

 Pol. Ind. Fondo de Llitera, Par. 82-83

E-22520 Fraga, Huesca (SPAIN) 

Tel. +34 974 47 48 04

+34 630 43 08 43



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When using heavy fuel oil of poor combustion properties in Diesel engines, there may appear phenomena that cause problems in their operation. Among these problems, the most well known are Scuffing and Liner Lacquering, which arise especially when running at full load.


A heavy fuel oil with poor properties of combustibility (of high density, high C.C.A.I., etc.) tends to take more time to burn than a fuel oil of higher quality.

Due to the prolonged time of combustion of the heavy fuel oil in the engine’s combustion chamber, the flame can come into contact with the cylinder wall and burn its protective film of lubrication oil. This can cause a process of abrasion or wear on the surfaces involved: cylinder liners and piston rings.

This phenomenon is termed scuffing and is characterised by the appearance of marks, abrasions, or scratches on these surfaces.

Liner Lacquering:

A heavy fuel oil containing a high quantity of polyaromatic hydrocarbons or higher percentages of asphaltenes and resins produces combustion residues with unburned particles able to adhere to the grooves of the cylinder liner that are designed to ensure the movement and distribution of lubrication oil.

The accumulation of these resinous-asphaltenic adhered substances forms a sort of coat of varnish or lacquer on the cylinder liner, a phenomenon known as liner lacquering.

Because of this, less lubrication oil is found between the surfaces in contact on the cylinder liner and the piston, and a greater quantity of oil reaches the combustion chamber and is burned.This causes increased consumption of lubrication oil, but only in most extreme cases does it cause damage to the engine.

The treatment of heavy fuel oil with high-quality additives, such as “rb bertomeu” beco F1/ASF and “rb bertomeu” beco F1-Ship, specifically formulated for Diesel engines in Cogeneration Plants and in marine vessels respectively, helps to minimise occurrences of these phenomena. A common experience is that the regular use of these additives (in addition to the main benefits of saving fuel, reducing corrosion and fuel oil sludge, etc.) causes consumption of lubricant oil to decrease by around 15-20 %, which is further evidence of their properties as improvers of combustion for asphaltenes and other heavy hydrocarbons.



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