4/23/13 Updates on improving refractory lining service life | Hydrocarbon Processing | March 2011 www.hydrocarbonprocessing.com/Article/2780144/Updates-on-improving-refractory-lining-service-life.html 1/8 COPYING AND DISTRIBUTING ARE PROHIBITED WITHOUT PERMISSION OF THE PUBLISHER Updates on improving refractory lining service life 03.01.2011 | Maity, M. , SABIC Technology Centre, Jubail, Saudi Arabia Tips help maintenance and operations care and maintain refractory products in high-temperature operations Keywords: The hydrocarbon processing industry (HPI) utilizes high-temperature conditions and relies on the performance of refractory lining for various furnaces and vessels. The total installed cost of refractories in HPI facilities is negligible compared to the total cost of the entire complex. However, refractory lining is very important and it plays a critical role in the total performance, profitability and reliable operation of the plant. There are several instances of refractory lining non-performances and premature failures resulted in unplanned emergency shutdown. We will discuss common problems and failures encountered in HPI facilities and some remedial measures to follow. Background. In the HPI, refractories are mostly installed on fired heaters, hydrogen reformers, ammonia primary and secondary reformers, cracking furnaces, incinerators, process gas boilers, catalytic cracking units, coke calciner, sulfur furnaces, utility boilers, air heaters, ducting, stacks, etc. Some of the listed equipment operate under high pressure, and operating temperature can vary from very low to very high (approximately 500°C to 1,600°C). Refractories play a critical role for the total performance and reliable operation of high-temperature processing units. Refractories can be the controlling factor in the success or failure of a furnace and vessel’s service life, as well as the safe and profitable operation of the plant. Most HPI facilities operate under continuous operating mode and will run for several years before a scheduled shutdown for maintenance or turnaround. Therefore, the prime objective here is equipment reliability. Also, in the HPI, the time between shutdowns and maintenance outages is increasing with the implementation of stringent quality control and preventive maintenance programs. The shutdown period is usually short in duration and is planned primarily for mechanical overhaul. The life and durability of refractory lining should not be the determining factor in the frequency and duration of shutdowns. In spite of its importance, refractories are, in many cases, neglected, misunderstood and abused, and the uncared for refractory can cause several problems during regular plant operations. The unexpected problems can cause an emergency shutdown or require longer maintenance time to rectify both the damages in the refractory lining as well as mechanical damages to unit equipment. Also, the sudden failure of the lining can pose a significant risk and threat to plant safety. Therefore, it is important for HPI facilities to optimize the lining reliability and performance in various applications. It may be possible to minimize refractory related problems and reduce unnecessary expenses by introducing sound engineering practices, following proven guidelines and sharing practical experiences while designing the lining and selecting construction materials, installation methods, etc. This article will discuss several common problems and failures of refractory lining and highlight important considerations to mitigate such problems. Common problems and failures. The performance of any lining in a furnace is considered to be reasonable when similar service lives are achieved on a regular basis. Premature lining failure may be defined as one that does not achieve normal or average performance and service life. The furnaces and vessels in the HPI do not consume the refractory with corrosive liquid metal, slag, abrasion, impact, etc., which are common in metallurgical furnaces. Refractory lining problems and failures are mainly due to thermo-mechanical stresses, erosion and chemical attack. The most common refractory problems as experienced in the HPI are: • Hot spots (higher casing temperature) • Excessive cracking • Spalling of lining (thermal, mechanical, structural) • Erosion and thinning of lining • Chemical attack/corrosion from process gases (such as hydrogen, carbon monoxide, sulfur dioxide, alkalies), flue gases (sulfur, sodium, vanadium), steam, etc. • Acid-gas dew-point corrosion of refractory and metallic parts • Partial melting and degradation of lining • Excessive shrinkage and development of gaps • Anchor failure and detachment of lining from wall • Failure of metal liner over refractory • Explosive spalling during dry out • Mechanical damages. The extent of damages and failures may vary equipment to equipment. Sometimes the problems appear within a short time of operation or during commissioning, and this can become a major concern. Most processing industries handle highly combustible hydrocarbons. Therefore, lining problems in critical pressure vessels and boilers are a major concern and, in many cases, causes immediate shutdown to avoid any accidents. HPI processing plants are complicated involving continuous chain reactions in the interconnected network of reactors, vessels and pipelines. Any problem in any particular vessel due to a refractory problem can result in a complete shutdown of the unit and/or the entire facility. Here are some of the common examples of refractory damage (Figs. 1–12). The reduction in lining thickness in the catalytic cracking unit is caused either by cracking and spalling due to heavy thermal shock or erosion by catalyst particles and subsequent hot spot or partial exposure of shell plate. Also, mechanical damage in the cyclones due to erosion of the lining and plate may disturb the unit operation. Failure of the lining due to inadequate anchor system is very common for all kinds of lining. Explosive spalling may be caused during the initial dry out due to uncontrolled heating.
Transcript
4/23/13 Updates on improving refractory lining service life | Hydrocarbon Processing | March 2011
COPYING AND DISTRIBUTING ARE PROHIBITED WITHOUT PERMISSION OF THE PUBLISHER
Updates on improving refractory lining service life
03.01 .201 1 | Maity, M. , SABIC Technology Centre, Jubail, Saudi Arabia
T ips help m aintenance and operations care and m aintain refractory products in high-tem perature operations
Key words:
The hy drocarbon processing industry (HPI) utilizes high-temperature conditions and relies on the performance of refractory lining for various furnaces and vessels.
The total installed cost of refractories in HPI facilities is negligible compared to the total cost of the entire complex.
However, refractory lining is very important and it play s a critical role in the total performance, profitability and reliable operation of the plant. There are several
instances of refractory lining non-performances and premature failures resulted in unplanned emergency shutdown. We will discuss common problems and failures
encountered in HPI facilities and some remedial measures to follow.
Background.
In the HPI, refractories are mostly installed on fired heaters, hy drogen reformers, ammonia primary and secondary reformers, cracking furnaces, incinerators,
process gas boilers, cataly tic cracking units, coke calciner, sulfur furnaces, utility boilers, air heaters, ducting, stacks, etc. Some of the listed equipment operate under
high pressure, and operating temperature can vary from very low to very high (approximately 500°C to 1 ,600°C).
Refractories play a critical role for the total performance and reliable operation of high-temperature processing units. Refractories can be the controlling factor in the
success or failure of a furnace and vessel’s serv ice life, as well as the safe and profitable operation of the plant.
Most HPI facilities operate under continuous operating mode and will run for several y ears before a scheduled shutdown for maintenance or turnaround. Therefore,
the prime objective here is equipment reliability. Also, in the HPI, the time between shutdowns and maintenance outages is increasing with the implementation of
stringent quality control and preventive maintenance programs. The shutdown period is usually short in duration and is planned primarily for mechanical overhaul.
The life and durability of refractory lining should not be the determining factor in the frequency and duration of shutdowns.
In spite of its importance, refractories are, in many cases, neglected, misunderstood and abused, and the uncared for refractory can cause several problems during
regular plant operations.
The unexpected problems can cause an emergency shutdown or require longer maintenance time to rectify both the damages in the refractory lining as well as
mechanical damages to unit equipment. Also, the sudden failure of the lining can pose a significant risk and threat to plant safety . Therefore, it is important for HPI
facilities to optimize the lining reliability and performance in various applications.
It may be possible to minimize refractory related problems and reduce unnecessary expenses by introducing sound engineering practices, following proven guidelines
and sharing practical experiences while designing the lining and selecting construction materials, installation methods, etc. This article will discuss several common
problems and failures of refractory lining and highlight important considerations to mitigate such problems.
Common problems and failures.
The performance of any lining in a furnace is considered to be reasonable when similar serv ice lives are achieved on a regular basis. Premature lining failure may be
defined as one that does not achieve normal or average performance and serv ice life.
The furnaces and vessels in the HPI do not consume the refractory with corrosive liquid metal, slag, abrasion, impact, etc., which are common in metallurgical
furnaces. Refractory lining problems and failures are mainly due to thermo-mechanical stresses, erosion and chemical attack. The most common refractory problems
as experienced in the HPI are:
• Hot spots (higher casing temperature)
• Excessive cracking
• Spalling of lining (thermal, mechanical, structural)
• Erosion and thinning of lining
• Chemical attack/corrosion from process gases (such as hy drogen, carbon monoxide, sulfur dioxide, alkalies), flue gases (sulfur, sodium, vanadium), steam, etc.
• Acid-gas dew-point corrosion of refractory and metallic parts
• Partial melting and degradation of lining
• Excessive shrinkage and development of gaps
• Anchor failure and detachment of lining from wall
• Failure of metal liner over refractory
• Explosive spalling during dry out
• Mechanical damages.
The extent of damages and failures may vary equipment to equipment. Sometimes the problems appear within a short time of operation or during commissioning, and
this can become a major concern.
Most processing industries handle highly combustible hy drocarbons. Therefore, lining problems in critical pressure vessels and boilers are a major concern and, in
many cases, causes immediate shutdown to avoid any accidents. HPI processing plants are complicated involv ing continuous chain reactions in the interconnected
network of reactors, vessels and pipelines. Any problem in any particular vessel due to a refractory problem can result in a complete shutdown of the unit and/or the
entire facility .
Here are some of the common examples of refractory damage (Figs. 1–12). The reduction in lining thickness in the cataly tic cracking unit is caused either by cracking
and spalling due to heavy thermal shock or erosion by cataly st particles and subsequent hot spot or partial exposure of shell plate. Also, mechanical damage in the
cy clones due to erosion of the lining and plate may disturb the unit operation. Failure of the lining due to inadequate anchor sy stem is very common for all kinds of
lining. Explosive spalling may be caused during the initial dry out due to uncontrolled heating.
Differential movement of the shell and lining due to a mismatch in expansion behavior, uncontrolled heating-cooling, mechanical stresses, etc., can cause various
problems in the lining. In many cases, localized hot spots or high temperatures are controlled by steam impingement to reduce the casing temperature and continue
plant operation. Reductions in thermal efficiency , as well as associated risks and plant safety , are major concern for such cases.
Failure analysis and corrective actions.
Refractory -lined equipment function as a sy stem. There are several interacting phy sical and chemical effects that may be ongoing, progressive, cy clic, etc., that will
definitely control the performance of refractory . Therefore, in most of the cases, it may be very difficult to conclude a single reason for nonperformance and premature
failure of the lining. Also, there are numerous precommissioning factors related to design, material selection, installation, etc., as explained prev iously that directly
4/23/13 Updates on improving refractory lining service life | Hydrocarbon Processing | March 2011
In some cases, the poor quality material or installation workmanship of the refractory may contribute to the problem. But it is also possible that a good quality
refractory or installation can give unsatisfactory performance because of a combination of other factors. The analy sis of any refractory problem should consider
numerous factors and identify the main root cause for the problems and select appropriate recommendations.
Identify ing the actual reason of non-performance for the lining is a difficult task, and this involves sy stematic study and analy sis of the problem. Reviews of
background information particularly design engineering, quality and source of material, installation procedures and records, operational records, post-serv ice
inspection and maintenance history are important for the root-cause analy sis. Awareness of the operational parameters and potential degradation mechanisms that
can lead to failure of the lining is essential to understand the problems and remedial measures. A thorough sy stem analy sis should result in a better understanding of
the various factors that control the performance of the lining and y ield in sound basis for corrective remedial measures and actions. Therefore, clues and relevant facts
of failure should be gathered, analy zed, explored and studied to make a meaningful conclusion. Collecting samples and selective laboratory testing should be part of
the failure analy sis, if required. Important factors responsible for the performance of the lining are briefly explained here.
Important factors governing refractory lining performance.
Whenever there are some problems in lining, we mostly conclude that either the refractory material was bad or the installation was poor. However, in reality , the
problems are probably due to a combination of multiple factors and may not be solely just one factor—poor installation or inferior refractory quality . Clients as well as
the project contractors, suppliers and others don’t alway s recognize that their actions and oversights can directly affect the performance of the lining.
To address the problems associated with refractories, it is necessary to recognize the main factors that are involved and contribute refractory related problems. These
factors are:
• Design of furnaces/vessels
• Design of refractory lining and detail engineering
• Selection of refractory materials and specification
• Quality of refractory materials
• Installation of lining
• Curing, startup and maintenance of lining
• Operation practices
• Inspection and maintenance practices.
It is important to give attention to these listed factors to avoid and minimize unexpected and premature failure or problems of lining.
Design of furnace/vessels. The performance and stability of the refractory lining depends on the structural design of the furnace and its configuration. Sometimes
adequate attention is not given to the refractory lining and its engineering related issues during early plant equipment design and detail engineering. One of the most
common observations is that the refractory designers or specialists are involved at the final stage of project implementation or during installation. This may lead to
several compromises with refractory -lining design and engineering practices as there is limited scope for change in vessel design, operating conditions and the process
to reduce the impact of these factors on lining performance.
The problem of refractory lining may be due to insufficient combustion volume. The heat released within the sy stem is more than absorbed by the process and is
dissipated through walls or exhausted with flue gases. In such cases, there are possibilities of the lining approaching the flame temperature and causing several
problems. The burner ty pe, its design, location, flame shape, possibilities of flame impingement, flowing pattern of flue gases, etc., may affect the lining. In many cases,
limited vessel dimensions, inaccessibility and complicated configuration restricts the best lining practices during initial construction as well as subsequent
maintenance and repair.
Design of refractory lining and detail engineering. The design and detail engineering of the lining for a furnace and vessel should be done on the basis of careful
analy sis of serv ice conditions, availability of refractory materials, thickness requirements, anchorage, ease of installation and future repair and maintenance.
Adequate knowledge on operating conditions that are active—such as temperature, pressure, chemical attack, thermal shock, abrasion, erosion, furnace gas
composition, mechanical movement, v ibration, etc.—should be very useful for the optimum lining design and selection of refractory . Chemical attack may occur from
gases such as steam, hy drogen, carbon monoxide, alkalies, sulfurous gases, etc.; these acid gases can initiate various problems in the lining, which are explained in the
literature. All of the important operating factors and any other criteria specific to the process under consideration should be verified for their possible effect on the
performance of the lining.
Thermal calculation is essential for any lining to ensure design casing temperature, temperature gradient in the wall and heat losses. Thermo-mechanical FEM analy sis
may be carried out for critical vessels and load bearing refractory structures to predict temperatures, stresses and displacements in the lining. The FEM analy sis is a
reliable tool to investigate the spalling mechanisms and to develop way s on improving the lining behavior.
Anchors are used for almost all ty pes of refractory applications. These are mostly metallic ty pe. Lining failures due to inadequacies in the anchoring sy stem are very
common (Figs. 6, 9 and 10). Selecting the proper metallurgy , anchor dimensions, configurations, and spacing are very important to achieve the maximum serv ice life
of the lining. Where metal liners are used over the lining, the mechanical design should be sound and allow free movement of the liner on one end from its fixed
positions.
Fig. 8. Ty pical refractory
lining failures—Acid
condensation below lining.
4/23/13 Updates on improving refractory lining service life | Hydrocarbon Processing | March 2011
While designing a new lining for a vessel it is important to consider ease of future maintenance and repair. However, this aspect of the lining design is compromised in
many cases because a lining sy stem that is maintenance friendly may be more expensive with respect to initial materials and installation expenses as compared to a
lining that is adequate to meet the initial contractual requirements.
Details of the lining lay out structure, thickness, dimension, shape and sizes of indiv idual bricks and other shaped items, their lay ing and bonding patterns, prov isions
for expansion allowances, support of brick-wall, etc., should be part of the detail engineering for each piece of equipment.
Finally , practical experiences and experience-based judgments are very important for successful and reliable design of any refractory lining. Therefore, involvement
of experienced engineers from the design stages to final implementation is one of the essential parameters to get the optimum performance of lining.
Selection of refractory m aterials and specification. The majority of refractories used in the HPI are alumina–silicate and high alumina varieties—both
insulating and dense ty pes. Mainly bricks, monolithics, ceramic fiber items, different ty pes of insulating blocks, etc., are used for lining. Bricks and monolithics are
available for both dense and insulating ty pes with a wide range of properties and each material has an application that is more suitable.
Selecting materials should alway s be based on properties and specifications suitable for the specific application and operating conditions. Most refractory materials
react and change during serv ice according to the principle of thermo-chemistry . It is important to know the furnace atmosphere, presence of any major or minor
chemicals and their possible effects on the lining. Selecting materials solely based on price and ease of installation should be avoided. Very often, monolithic lining
sy stem is selected in the lining design of critical vessels where brick lining or some other design may be more suitable. The selection may be due to cheap and easy
availability of monolithics and easier installation than brick lining and to avoid preparation of too many engineering drawings for the complicated brick shapes and
lay ing details. In many cases, recommendations of refractory manufacturers are biased and based on their available product ranges, which may not be appropriate for
the required conditions.
Selection should be based on the desired serv ice life and cost considerations. Initial cost of refractory lining should not be the selection criteria but rather the serv ice
life of lining under operating conditions. It is better to develop the material specification for any application based on discussions with the manufacturers to ensure it is
more practical and realistic. The specification should be regularly rev iewed and updated based on actual performance of used materials and current industry practices.
Quality of refractory m aterials. Refractory materials are heterogeneous, and quality varies both as manufactured and as installed. Materials should be procured
against specifications most appropriate to the specific application. For critical applications, purchasing of materials based on a comparison of product datasheet or
catalogue specifications or equivalent principles should be avoided. The actual performance references and records for specific products or brands should be verified
against similar applications. Rev iews of manufacturing facilities and quality -control program, and random inspection and testing of important properties are essential.
Lining installation. Unlike other engineering subjects, there are very few well-established and recognized engineering standards, design and installation guidelines
for refractory jobs to ensure quality installation of the lining and its subsequent satisfactory performance. In many applications and contracts, the only quality
assurance is limited to warranty and guarantee of material and lining for a limited operating period. Installations of refractory rely upon manpower. Because of the
human element, care should be taken to ensure involvement of only experienced manpower in the installation. Developing job specific installation procedures, quality
plans and acceptance criteria of the installed lining, prequalification materials, and installation crew are some of the important factors that companies must address
4/23/13 Updates on improving refractory lining service life | Hydrocarbon Processing | March 2011
API 936 guidelines, developed by the American Petroleum Institute (API) are very useful tools for quality control of monolithic lining. There are also some
specifications and standards developed by Process Industry Practices (PIP) especially for process industries. Prequalification of materials, installation procedures,
machinery and crew, testing of as installed samples, ambient condition monitoring, acceptance criteria for installed lining, involvement of neutral inspection agency
for quality monitoring, etc., are important requirements of these standards. Many clients and licensors have started recommending compliance to these guidelines for
critical applications. Possible quality control for brick and ceramic fiber lining in similar lines are expected to improve quality for the total installation job and
compliance to engineering practices.
Using common standards and guidelines will help the industry to mitigate installation problems. This also helps in developing quality installation manpower that are
actually executing the jobs in the field, particularly crews, masons and superv isors.
Dry out and heat up. The heat dry out of a new lining, particularly monolithic lining, is a critical step when considering the total quality for the installation. Slow and
controlled removal of free and chemically bonded water from the lining sy stem is essential before actual startup of the unit. Explosive spalling or cracking may occur
in lining when quick and uncontrolled initial heat up or dry out of the refractory is done.
Also, alkali hy droly sis is a major concern for monolithic lining in tropical and subtropical weather conditions. Dry -out needs to be done at the earliest to prevent
damage. When delay s in dry out or complete dry -out are not practical, suitable sealants may be used on monolithic lining to reduce alkali hy droly sis reaction and
damage. Also, natural-air circulation should be maintained within the furnace to avoid hot and humid conditions.
Developing job specifications for the dry out schedule is essential instead of following general guidelines from the supplier. Burner size and location, exhaust location,
air volume, velocity , temperature-control locations, etc., need to be properly addressed. Permanent burners or special external burners may be used for dry out
depending on requirements. Permanent burners have limitations of inadequate temperature control at the initial stage. Many specialized dry -out agencies are
available to carry out this job in most professional manner.
Unit operation. Production and operation personnel should be aware of the process parameters that may affect the serv ice life of the refractory lining for furnaces or
reactors. Minor changes in operating conditions and processes may strongly influence the performance of any lining. Abnormal changes in burner operation—such as
flame impingement on refractory surface, incomplete burning of fuel causing change in furnace atmosphere, changes in temperature, pressure, fuel quality (dirty fuel),
heating and cooling rate, etc.—have direct effects on the refractory lining. Operating at a higher temperature than specified in the design can reduce the serv ice life of
the refractory . High limit thermocouples should be located at strategic positions for monitoring and controlling temperatures within the sy stem.
In many cases, the problem or initiation of deterioration in lining due to operational issues may not become v isible immediately . Therefore, it is important to gather
information on operational information and records while study ing the problem.
Inspection and m aintenance. Regular inspection of the lining and condition monitoring should be part of the operating plan for critical equipment. The frequency
of inspection may be decided based on historical problems, severity of operating conditions, complexity of design and other factors. Timely identification of problems
and corrective actions may lead to longer life of the lining. Temperature-sensitive paints are widely used to monitor casing temperature and locate hot spots. Infrared
thermography is an important tool for online-temperature measurement, condition monitoring of lining, predicting problems, and maintaining equipment uptime
during a problem.
Thermography is very useful for locating and monitoring effected areas in case of any operational upset or localized problem in the furnace, and thus allowing the
inspectors insight into what is happening inside the lining. This allows the plant to make appropriate decisions in planning the shutdown schedule and maintenance
repairs and estimating the total materials needed for these repairs.
The maintenance strategy for refractory linings should be based on cost-effective proactive sy stems rather than on conventional reactive sy stems. The probable
reasons and mode of failure should be ascertained before redesigning or repairing a lining. Change in lining design and installation practices without proper analy sis of
factors limiting the serv ice life of the existing lining may not be a long-term solution. All repair and maintenance jobs should be treated like a new job with proper
quality control. It is important to inspect and record all repairs to maintain a proper trend and database.
Other factors. There are many other factors that may directly or indirectly affect the performance of the lining. In most construction sites, refractory installation is
one of the last activ ities. With any delay in other pre-activ ities, there is alway s pressure on shortening and possibly compromising the refractory installation schedule
to make up for earlier delay s. This attitude of getting the job done fast may have major adverse effects on quality .
Ambient temperature and working conditions for workers have direct effects on the quality of the installation job. Implementing cost-cutting measures, purchasing
refractory and selecting the contractor solely on the basis of commercial issues with less importance on quality , serv ices, etc., may be the contributing factors to poor
performance over the longer term.
Fig. 11. Ty pical refractory
lining failures—Brick wall
bulged.
4/23/13 Updates on improving refractory lining service life | Hydrocarbon Processing | March 2011
Refractory is a diverse class of materials that are used to insulate and protect industrial furnaces and vessels. The properties of the refractories are tailored to specific
applications by vary ing the composition of raw materials. The technology of refractories is making remarkable progress recently . Developments in refractory lining
design sy stem and performance specifications with as-built quality requirements are very important for this specialized field. With every lining failure, there is a degree
of uniqueness that results from variability in design and application, complexity of serv ice conditions and material behavior. Awareness of the potential degradation
mechanisms of lining and operating parameters is essential to mitigate such problems. Implementing various quality control programs, advanced installation
procedures and online inspection can contribute to satisfy results. HP
BIBLIOGRAPGHY
American petroleum Institute, “API RP 936, “Refractory installation quality control guidelines-inspection and testing monolithic refractory linings and materials.”
Biglin, J., “Refractory Maintenance and repair,” The American Ceramic Society Bulletin, Vol.7 5, No. 5, May 1996.
Crowley , M. S., “Design better vessel linings,” Hydrocarbon Processing, December 197 9.
Devera, D., “After installation the importance of a controlled dry -out for castable refractories,” The Refractories Engineer, July 2003.
Gardner, A., “FCC Cy clone Refractories,” Today’s Refinery, November 1998.
Hanley , R. M., “Refractories utilization in the hy drocarbon processing industries,” The Refractories Engineer, July 2000.
Hancock, J. D., “Practical Refractories,” Cannon & Hancock CC.
Heard, N. E., “Quality Control Practices in the US Petrochemical Industries,” Unitcer, 1989.
James, S., “The Fundamentals of Refractory Inspection with Infrared Thermography .”
Schacht, C. A., Refractory Linings, Marcel Dekker, Inc.
Semler, C. E., “Overv iew of refractory problems in industry ,” Interceram, Vol.40, No.7 , 1991.
T he author
Manabendra Maity is working as a refractory specialist at the Materials & Corrosion Section of Sabic Technology Centre, Jubail, KSA. He holds B.Tech
degree in ceramic engineering from Calcutta University and a M.Tech degree in ceramic engineering from IT-BHU, India. He has more than 16 y ears of
extensive experience in refractory lining design, engineering, installation & quality control, failure analy sis and troubleshooting for furnaces and vessels
for the refining, petrochemical and metallurgical industries. He started his career in 1994 as a refractories & non-metallics engineer in Engineers India
Ltd., New Delhi and continued there until 2007 . It was followed by two y ears in Ciria Div ision of Thermal Ceramics. Mr. Maity is life member of India
Ceramic Society & Indian Institute of Ceramics. He has qualifiedfor API-936 Refractory Personnel Certification Program.
what is normal pitch for anchors in castable lining
Refractory break down in boiler
a. overheating b.moisture present during start up c. Highly fluctuating temperatur/load d. excessive v ibration
which one or which all are causes frm these option?plz rply
I am working on an enquiry to prepare estimae for HDRI Feed bin of a Steel manufacturer. Need help to know what are liner plates used for
refractory in such ty pe of bins. They need liner plates 10mm.
Y ou have mentioned dry out has to be as earliest after castable refractory lining. If the commissioning is delay ed for months after the
dry out is there any preservations required for the lined dry ed out refractory castable? Can we box up the heater and forget till start up?
Please indicate y our v iews.
20-01-2012
Dear Friend:
Hope y ou have a great day !
Sinabuddy Mineral Co.Ltd is one large manufacturer of Refractories Materials in China and knew y ou are one of the importers in Refractory .
4/23/13 Updates on improving refractory lining service life | Hydrocarbon Processing | March 2011
