Services - Heat Treatment Services
Heat treatment is one of the most critical stages in manufacturing of
rotary and fixed equipment in oil, gas and petrochemical industries. In
general, it includes heating and cooling the metal equipment to achieve desired
properties. The main reasons why heat treatment is required, include:
- Relieving stress and tension caused by
fabrication and welding operations
- Modification of size and structure of
metals
- Creating a smooth metal surface, thereby
increasing the reliability of the surface tensile strength of the metal in
contact with the fluid
- Improving steel properties in order to
make it possible to replace the more expensive steel types with the cheaper
types and consequently increasing the economic efficiency
- Increasing absorption of the impact
energy of steel
- Improving the cutting properties of the
tool steels
- Improving electrical properties
- Modification or improving magnetic
properties
The requirement for heat treatment is primarily specified by codes and
standards on one hand and with regard to the application of the equipment and
the type of services they are ought to provide on the other hand. Heat
treatment can be conducted through different methods.
MFS is capable of providing the following heat treatment methods:
1.
Heat treatment using stationary furnace
2.
Heat treatment using mobile
furnace
3.
Heat treatment internal firing
4.
Topical heat treatment
Heat Treatment Using Stationary Furnace
After completion of design, simulation of the furnace performance with aid
of computing simulation software and evaluation of operation of the furnace (to
find the best and most efficient arrangement of burners, thermocouples and
dampers), MFS heat treatment furnace was fabricated with the following
specifications.
Specifications of MFS stationary furnace
- Applicable dimensions 20×9×9 meters.
- Applicable for both complete and topical
heat treatment operations
- Capacity to handle a single 200,000 kg
piece without limitation in thickness
- Heating up the pieces up to 1200 0C
- Thermal capacity 12,000,000 kcal/h with
high velocity burners
- Fully automatic control system
- Dual fuel including LPG and CNG
- Transporting pieces inside the furnace
with railed trolley
- Insulation with ceramic blanket
Advantages of MFS furnace
- Utilizing years of experience in MFS and
taking advantage of the capabilities of specialized operators and engineers
- One of the largest and most modern heat
treatment furnace in Iran
- Working with both CNG and LPG, reducing
the production of environmental pollutants.
- Reducing the risk of damage to sensitive
components used in sour service, caused by contaminants in fuel
- Increasing energy efficiency due to
minimized waste of energy
- Amongst the major causes of damage and
distortion in components, temperature
difference in different parts of the furnace can be noted. For this reason ASME
standard allows 46°C temperature difference. Using an exclusive design, despite
affording higher expenses, MFS has reduced temperature difference to 8°C
- Utilizing high velocity burners to
enhance air and fuel mixing and combustion and also to create thermal integrity
in furnace area
- Ability to provide continuous graphs and
reports at any stage of the operation
- Precise control of the components and
furnace temperature using PLC control system with the ability to control
burners, fuel gas and air inlet vanes and flue gas outlet from furnace stacks
- Using 250mm ceramic blanket as
insulation in order to minimize heat loss and reach thermal integrity in
furnace area
- A removable door, adjustable to size of
different pieces, for hazardous area classification zone 4.
- Ability to conduct heat treatment on
components which are lengthier than furnace
Heat Treatment Using Mobile Furnace
Another service
of the company is performing heat treatment using mobile furnace. In a way that
first all sides of the component is insulated and covered by temporary structures
in an allowable distance, then the burners which are located at regular
intervals from the component will heat up the component indirectly. The
advantages of this method include the possibility to assemble and dismantle the
furnace promptly and that it does not require large separate spaces .For this
method, MFS has mobile control panels which can be located around the component
enabling the operator to control the operation. Component will heat up the component
indirectly. The advantages of this method include the possibility to assemble
and dismantle the furnace promptly and that it does not require large separate
spaces. For this method, MFS has mobile control panels which can be located
around the component enabling the operator to control the operation.
Internal Firing Method
MFS also offers
Internal Firing as another method of heat treatment. Instead of moving the
component to stationary furnace or even providing mobile furnace, it is heated
up inside out through combustion gases and by transferring the hot fluid flow
to the nozzles located on the component. This method is basically used for Post
Weld Heat Treatment and Refractory Drying. It is mainly conducted on pieces
which are large in size and weight and costly to move. It should be noted that
this method is not recommended for components with internals. In this method
heating is done through combustion burners and temperature control is done
through thermocouples attached to the body of the component. It is important to
stay alert of the rate of heat increase during internal firing operation to
prevent probable damages which are caused by sectional overheating.
Topical Heat Treatment
One of the most
common heat treatment methods for stress relieving, pre-heat Treatment,
annealing and PWHT is Topical Heat Treatment, which can be done through two
different techniques, namely Inductive and resistance. MFS applies Resistance
heat treatment using flexible ceramic thermal elements. These elements consist
of nickel chrome wires coated with alumina ceramic and are directly attached to
the component. Temperature control is done by k-type thermocouples which are
placed between the elements and are connected to thermo regulator and recording
device. Inductive and resistance topical heat treatment are mainly used for
heating the peripheral weld lines, small components and field activities on
storage Tanks and components which are hard to move.
MFS applicable Heat Treatment Techniques
1. Post weld Heat Treatment
2. Annealing
Annealing is a
thermal operation cycle which can improve the ductility properties of a
component. After forming processes like rolling, extruding, forging etc., ductility
of component deteriorates to some extent; in this situation annealing can be
used to modify the component’s micro structure improving its dynamic properties.
During this process, firstly according to the related codes of standards the
component is exposed to temperatures higher than Austenite Temperature for a
few times. Then based on the material type, annealing is applied in open air or
even through quenching in water or cold oil or in furnace to improve its
mechanical and structural properties.
3. Normalizing
Normalizing is a
heat treatment technique which is mainly applicable for ferrous metal parts. In
addition to operation temperature this technique also differs from annealing in
cooling rate, which is done by air in normalizing.
The main objective
of normalizing is to eliminate internal stresses caused by operations like
topical heating of the welded part, casting, forging, forming and machining.
4. Stress Relieving
5. Quench&
Tempered
Technical and Engineering Capabilities
Mechanical and
process equipment for oil, gas, petrochemical, and power plant industries, MFS
recognized the necessity for an exclusive heat treatment furnace for large
scale industries to be accountable to the requirements of clients in the above mentioned
industries. Finally in 2011, MFS fabricated its furnace in accordance with
market requirements.
MFS takes
advantage of a knowledgeable and experienced engineering team with high
proficiency. During numerous projects, MFS has been responsible for preparing
the instructions and procedures for heat treatment and stress relieving and is
completely acquainted with the standards, Project specifications and client
requirements. Consequently having a state of the art furnace alongside highly
qualified engineering staff, MFS is now capable of conducting heat treatment in
full compliance with ASME sec VIII UCS 56. We have trained our operating and inspection
staff in a way that after completing a heat treatment operation, they provide
our clients with a report including charts and curves of different stages of
operation in accordance with standard principles. If required, they are also
capable of measuring hardness, the amount of ferrite and any other requested parameters
using calibrated measuring tools under the direct supervision of our clients.