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



n. 12    

"rb bertomeu" bewax OB

In order to prevent problems caused by the solidification of paraffin contained in gas oils in general, additives are used as depressors of the CFOP that modify the structure and behaviour of the paraffin crystals formed when the temperature falls below 0º C. These additives are added at source by each manufacturer or supplier of gas oil, in sufficient quantity to reach the minimum CFOP temperatures specified for each type of gas oil by law in each country (according to the annual temperature range). In Spain and neighbouring countries, the gas oils used in winter and summer have a different CFOP specification because the ambient temperature is very different in each season. Thus, whilst the CFOP specified for summer is at 0º C, that specified for winter is -10º C (automotive Diesel fuel in Spain).
On numerous occasions, it is advisable to resort to further additive treatment of the gas oil available with the antifreeze product "rb bertomeu" bewax OB, to prevent problems of fluidity. For example:

  • When a user of winter gas oil intends to drive the vehicle in regions where the ambient temperature may fall below the -10º C guaranteed in the supplier’s specification.
  • When a user of summer gas oil needs to keep a store or consume it during the winter period, for whatever reason.
  • When there is uncertainty as to whether the gas oil has an adequate CFOP.

The efficacy of further additive treatment with antifreeze depends largely on the type of gas oil and the additive treatment at source (type and quantity). For this reason, not all antifreeze additives are effective in all circumstances; therefore, the antifreeze for gas oil "rb bertomeu" bewax OB covers a wide range of eventualities, allowing for a significantly improved CFOP of the gas oil in use, providing reductions of between 4º and 10º C on the initial CFOP. At periodic intervals, we perform tests in order to monitor the reduction in the CFOP on samples of gas oils of various brands obtained from different Service Stations. In the most recent sample test performed on a sample of winter gas oils, the following reductions on the CFOP at source were obtained when applying additive treatment using the antifreeze "rb bertomeu" bewax OB at a ratio of 1 - 2 parts per thousand:



Obstrucción Point

Obstrucción Point


Several samples of

(CFOP) at source

(POFF )reached


Diesel oil in Spain, from


when using


Service Stations

guaranteed     analized

bewax OB


No. 1(automotive)

- 10º C              -14º C

-18/- 19º C


No. 2(automotive)

- 10º C              -14º C

-16/- 23º C


No. 3(automotive)

- 10º C              -10º C

-16/- 20º C


No. 4(heating)

-6º C              -9º C

-14/- 16º C

In most situations, this reduction in the Obstruction Point, of between 4 and 10º C, reached from the antifreeze treatment with "rb bertomeu" bewax OB, prevents awkward problems.
For further information on this subject, consult the following documents compiled by rb bertomeu (by clicking on the chosen title):




Click here to view previous bulletins.
Manufacturer of additives for fuel oil and crude oil
(c) rb bertomeu, S.L. - Copyright