A substrate steel of the comprising from 0.01 to 0.60 wt. % of La, from 0.0 to 0.65 wt. % of Ce; from 0.06 to 1.8 wt. % of Nb up to 2.5 wt. % of one or more trace elements and carbon and silicon may be treated in an oxidizing atmosphere to product a coke resistant surface coating of MnCr.sub.2O.sub.4 having a thickness up to 5 microns.

A substrate steel of the comprising from 0.01 to 0.60 wt. % of La, from 0.0 to 0.65 wt. % of Ce; from 0.06 to 1.8 wt. % of Nb up to 2.5 wt. % of one or more trace elements and carbon and silicon may be treated in an oxidizing atmosphere to product a coke resistant surface coating of MnCr.sub.2O.sub.4 having a thickness up to 5 microns.

The present disclosure relates to a heat transfer tube including an inner surface and an outer surface. The heat transfer tube further includes a first mixing element and a second mixing element disposed on the inner surface of the tube and projecting inwardly toward a central longitudinal axis of the tube. Adjacent mixing elements are separated by a gap arc distance of about 0.5 inches (1.27 cm) or greater. The first helical row has an angle () from about 15 degrees to about 85 degrees relative to the central longitudinal axis of the tube. The tube has an inner diameter of about 1.85 inches (4.7 cm) or less.

The present disclosure relates to a heat transfer tube including an inner surface and an outer surface. The heat transfer tube further includes a first mixing element and a second mixing element disposed on the inner surface of the tube and projecting inwardly toward a central longitudinal axis of the tube. Adjacent mixing elements are separated by a gap arc distance of about 0.5 inches (1.27 cm) or greater. The first helical row has an angle () from about 15 degrees to about 85 degrees relative to the central longitudinal axis of the tube. The tube has an inner diameter of about 1.85 inches (4.7 cm) or less.

A substrate steel of the comprising from 0.01 to 0.60 wt. % of La, from 0.0 to 0.65 wt. % of Ce; from 0.06 to 1.8 wt. % of Nb up to 2.5 wt. % of one or more trace elements and carbon and silicon may be treated in an oxidizing atmosphere to product a coke resistant surface coating of MnCr.sub.2O.sub.4 having a thickness up to 5 microns.

A substrate steel of the comprising from 0.01 to 0.60 wt. % of La, from 0.0 to 0.65 wt. % of Ce; from 0.06 to 1.8 wt. % of Nb up to 2.5 wt. % of one or more trace elements and carbon and silicon may be treated in an oxidizing atmosphere to product a coke resistant surface coating of MnCr.sub.2O.sub.4 having a thickness up to 5 microns.

In chemical processes for cracking hydrocarbons, reactors are subject to coking. This results in carburization of the metal substrate for the reactor leading to a reduced reactor life. If the reactor is subject to a decoke process, followed by a steam scour and nitriding there is a reduced tendency to carburization of the metal substrate improving the reactor life.

In chemical processes for cracking hydrocarbons, reactors are subject to coking. This results in carburization of the metal substrate for the reactor leading to a reduced reactor life. If the reactor is subject to a decoke process, followed by a steam scour and nitriding there is a reduced tendency to carburization of the metal substrate improving the reactor life.

The disclosure relates to an anti fouling composition including a metallic component comprising of at least one alkali metal salt and a non-metallic component and method for preparation of anti fouling composition. The disclosure also relates to a process of reducing fouling in reactors or furnaces using said composition.

The disclosure relates to an anti fouling composition including a metallic component comprising of at least one alkali metal salt and a non-metallic component and method for preparation of anti fouling composition. The disclosure also relates to a process of reducing fouling in reactors or furnaces using said composition.