Panipat Lining Inst

Revamp Job I.P.C.LVadodara GUJARAT, INDIA

LINING INSTALLTION INSTRUCTIONS FOR CRACKING UNITRADIANT SECTION, TRANSITION ZONE, COLLECTOR, DUCT AND STACK,

CONTENTS

1. SCOPE 2. REFERENCE DOCUMENTS 3. TYPE OF LINING 4. LINING INSTALLATION SEQUENCE 5. LINING INSTALLATIN DETAIL

6. QA-PLAN FOR SITE INSTALLATION ACTIVITY

1. SCOPE: This document covers the installation sequence and modalities for Installation of Refractory Lining materials viz. CFB Modules, Pyro module, Ceramic Fiber blankets, Castables, and Bricks, etc. for cracking furnace radiant section, Transition zone, collector, shadow boxes, ducts & stack. The document also describes the storage requirements of the materials & Quality Control requirements during installation. 2.

REFERENCE DOCUMENTS: Lining arrangement and relevant details are shown in the drawings made for the subject job. The List of Drawing & documents is attached along with this document as an Annexure- A1.

3. TYPE OF LINING: The various parts of furnace shall be lined as indicated in the relevant detailed drawings. And listed in Annexure- A2 (Tabulate Detail of Lining Description). 4. LINING INSTALLATION – SEQUENCE: The sequence of installation of refractory for various parts of the subject unit is shown as bellow.

4.0

LINING INSTALLATION - SEQUENCE: • • •

• • • •

• • •

5.0

Radiant lower walls brick lining Wall burner blocks installation Upper walls Module lining Radiant Arch module lining Transition Zone wall module lining Transition floor lining with bottom bull nose lining Radiant floor lining Castable lining of Collector, Duct & Stack are to be lined at ground Trough CFB lining is to be done at ground and its erection will be done at last. Shadow boxes ceramic fiber blanket lining

LINING INSTALLATION - DETAILS: While executing refractory linings extreme care shall be taken to install the right materials in the proper way and manner for attaining the best properties and life of linings. The installation and its requirements may be broadly classified as, 5.1 5.2 5.3 5.4 5.5

Anchor Layout and Welding. Surface Preparation. Lining Installation. Equipments, Tools and Tackles for Installation. Drying out.

5.1

Anchor Layout and Welding Anchor layout is the first process in refractory lining installation and is very critical in some areas like Ceramic fiber Module installation where the dimensional tolerances for anchors are kept to the minimum. Anchor pitch and layout are given in the relevant

drawings. The drawings are laid out and orientation of the plates is checked to establish the correctness of the grid lines. Initially the out line and cut outs like openings for the doors, peepholes, burner blocks etc are marked out. Then lines parallel to both length and width of the panel as per anchor spacing are marked and intersecting points are punched to give the anchor positions. Locations of any special anchors around openings or objects are also marked out as per drawing thus completing the anchor lay out.

5.2

Prior to welding of anchors, initially spot grinding of the area around the anchor position is carried out to ensure that the anchor has welded on clean (steel) surface. Welding is done under carefully controlled conditions and care taken to ensure undercutting of anchors does not happen. Care should also be taken to prevent threads of studs being damaged by any welding flux. Also prior to welding the type of anchor and location should be verified to prevent welding of incorrect anchors. Surface Preparation Surface preparation shall be as per CIRIA standards wherever it is applicable / as per drawings. At other areas the surface to be refractory lined shall be cleaned of heavy rust or mill scale, dust, loose particles oil etc., by wire brushing.

5.3

Lining Installation. The lining installation for this furnace basically consists of the following lining combinations, which has to be meticulously followed in addition to the specific requirements of each locations described along with. 5.3.1 Corrosion resistance coating 5.3.2 Ceramic fiber Modules (Z Blok-3, Pyrofold M, Pyro M module &Pyro T Bar Module) with CF Blanket as back up. (for typical detail of Modules refer drawing No.VD-8668.) 5.3.3 Ceramic Fiber Blanket Lining. 5.3.4 Brick with back up Block Lining. 5.3.5 Castable with backup block lining. 5.3.6 Castable Lining.

5.3.1 Corrosion resistance coating Corrosion resistance paint (Shalikote) to be applied wherever the shell plate is in contact with ceramic Fibre blanket. 3mm layer is be built up uniformly on the shell plate either by hand or by a soft brush and allowed

to dry. Precautions should be taken to avoid damage to the coating in the form of mechanical damage, rain etc.

5.3.2 Ceramic Fiber blanket as back up for CF modules A) Locations Used : Radiant Upper Walls, Radiant Arch and Transition zone Arch & side walls. B) Procedure The lining of both the Radiant and Transition zone arch are to be carried out after erection of the same and in position. Walls lining are to be lined after erection of burner block as insitu. As described above, the stud welding has to be completed as per the layout shown in the drawing and painting as per CIRIA Specification furnished, prior to commencing the lining installation. Stud welding and painting can be done in at ground or insitu.

Back up blanket lining is a simple installation; however care should be taken to ensure that tight compression joints are obtained between adjacent blanket butt joints. Blanket lining can be held in place using rubber bands. The lining is to be done as followings:Lining has to commence from the Side wall. One layer of blanket is impaled on the studs starting from a bottom end corner with the blanket length vertical. While installing the adjacent blanket, care to be taken to ensure that joints are tight. Typical compression joint detail has given bellow in the sketch. Back up blanket is laid completely including one blanket on the end wall from where module lining is to start. Similarly prior to lining of each wall, the back-up blanket lining has to be completed.

Once the back-up lining is completed Module lining can commence.

Note: The anchor for vacuum formed peephole block should be welded simultaneously along with the installation of vacuum formed peephole block in the trough.

The detail of module installation has given in the Installation Manual.  

   

5.4

5.5

5.6

5.6.1 5.6.2

5.6.3 5.6.4 5.3.3

Ceramic Fibre Module Lining Systems CONTENTS

A

Introduction Ceramic fiber products are extensively used in the lining of furnaces. And products are used basically due to its light weight, low thermal conductivities and thermal shock resistance etc. General •

Design Considerations

•

Design Check List

B

•

Surface Preparation

•

Installation Sequence

Installation • •

Equipment Check List Installation Procedure of Z-Blok 3 modules: Step 1 - Marking out the anchor pattern Step 2 - Grinding anchor positions Step 3 - Anchor welding Step 4 - Application of coating / painting Step 5 - Starting a row of modules Step 6 - Installation of a module Step 7 - Completion of the module installation Step 8 - Packer details Step 9 - The module installation is built up in rows Step 10 - The plastic bands are removed Step 11 - Finishing process Step 12 - Completion of module lining installation

• •

Installation Procedure of Pyrofold M modules: Installation Procedure of Pyro M & Pyro T- Bar corner modules. Detail of procedure is attached at last A

GENERAL Design Considerations Z-Blok 3 Modules are designed to be installed in a soldier course fashion with packing strips between each row of modules. Figure 1 shows the layout of a typical Z-Blok 3 Module installation. When using the soldier course system in overhead applications packing retaining staples (U-Pins) may be used.

Figure 1 - Typical Z-Blok 3 Module Lining and Anchor Layout

Prior to installing the Z-Block 3 Modules, it is necessary to lay out the anchor pattern and weld the anchors in place. At this point coating / painting & blanket backup can be applied. While installing the back-up blanket the butt joints should be tight compression joints as shown in drawing. Once the anchors and backup materials are in place, the Z-Block 3 Modules can be installed. The Z-Block 3 Module is easy to cut or trim to allow for obstructions such as burners or inspection doors. Best results will be achieved if the module is trimmed, so that the anchor tubes will remain in line with the pre-determined anchor pattern. It is best to cut less than necessary and compress the module into place to ensure the tightest possible joint. Design Check List

When planning to carry out a modular lining a simple checklist of items required to ensure a trouble free installation. • Required Ceramic Fiber Modules as per drawing. • Check: Temperature grade, Density & thickness of the modules, to ensure that the correct modules are being installed. • Ceramic Fibre blanket packing is 128Kg/M3 X 25mm thick, of the same temperature grade as the module, cut into strips with L shaped edges as described in this document. • Anchor sets of the correct length depending on backing lining. Note one anchor set extra is required per row of modules. • T Bar yokes. Note one T-Bar yoke extra is required per row of modules. • Packing retaining staples, necessary for overhead applications. Suggested centers are one staple at 600mm to 900mm centers depending on lining thickness and application. • For casing coatings, check the thickness of coating required and quantities of material. The coating shall be as per CIRIA painting standards. Surface Preparation (The steel surface to be lined should be free of heavy rust or scale, non-conductive paints, dried refractory cements or oil. Wire Brushing will be required to clean the surface. Local cleaning is recommended at each anchor location prior to welding. Set up good scaffolding so there will be easy access to the areas to be lined. Also, make arrangements for the material to be as close to the work area as possible without being in the way, so it can be efficiently delivered to the working crews. Installation Sequence A furnace with four fixed walls and a roof should be lined in sequence to ensure an open face during the installation. Ceramic fiber Module lining of side walls shall be done first after that end walls lining. Top most one or two row of walls ceramic fiber Modules shall be installed after completing the arch lining and then the left out one or two row of walls lining shall be completed. Figure 2 - Installation Sequence for a Four Fixed Wall Application.

B

INSTALLATION

Equipment Check List The following list details the basic equipment required to carry out a typical Z-Blok 3 Module installation. • Welding equipment suitable for welding of studs • Hand Tools. • Measuring Tape • Chalk line • Angle Grinder • Long sharp knife suitable for cutting Ceramic Fiber. • A means of cutting SS tubes in the modules and T Bar arms. • Slip plates (approx 1mm) sheet steel or plastic (lining thickness x 600mm) to allow modules to slide into position during installation. • 10mm socket and extension bar suitable to access the locking nut, through the thickness of the lining. • Tools to adjust welder; screwdriver, pliers, hexagonal keys etc. • Tamping tool to finish the surface. This can be formed in wood or expanded metal (300x 250mm).

Installation Procedure of Z-Blok 3 Modules The Z-Blok 3 Modules are installed in a soldier course layout with a packing strip between rows. (Figure 1). The Z-Blok 3 Module requires a pre-determined anchor pattern so the first step is to establish the layout.

Step 1 Measure the correct distance vertically and horizontally and mark with a chalk line. Typically, the soldier course anchor spacing is 290mm horizontally and 430mm vertically, as shown in the drawing.

Step 2 At the points where the chalk lines cross it is good practice to spot grind an area approximately 10mm diameter to ensure that the weld is made onto clean steel. This is especially important on old steel casings.

Step 3 At the points where the chalk lines cross, weld a T Bar anchor onto the steel casing

Step 4 If coating / painting is being used it is a good idea to protect the threads of the anchors by installing plastic covers over the anchors. If a coating is not being used, plastic covers for the anchors are not needed. At this point, back-up layers of

blanket and Aluminium or Stainless Steel foil vapour barriers should be installed if being incorporated into the lining of the furnace.

Step 5 When the necessary backing coatings and or linings have been installed the Z-Blok 3 Modules can be installed. The modules are installed in rows therefore at the start of a row remove the arms from one side of a T Bar yoke. Locate the T Bar yoke onto the anchor, which has been welded to the wall previously, fixing it into position with a locking nut.

Step 6 The tubes in the module are then located onto the arms of the T Bar yoke, another T Bar yoke is located into the tubes in the opposite end of the module. The module is then compressed into position.

Step 7 The sequence is completed by fitting the T Bar yoke onto the anchor and securing with the locking nut.

Step 8

The procedure mentioned above is repeated until the row is completed. Before commencing the installation of another row of modules a packing strip of Ceramic Fibre blanket should be installed (folded & compressed as per lining arrangement & detail drawing). This blanket packer should be jointed using a staggered joint and not exceed 2 metres in length.

Step 9 When the packing strip is in place the next row of modules can be installed. The anchor positions will ensure that the modules are compressed during installation. The use of thin steel or plastic plates allows the modules to be slid into position making the task of obtaining the necessary compression easier. Step 10 The lining is carried out as described above till the end of the row is reached. For the last but one module a half split yoke is used to complete the Z-Blok 3 lining with one module space at the end left vacant. Because of this the split yoke can be easily fixed. For the last module a center fixing module Pyrofold M Module is used which can be easily installed and fixed to the prewelded shell as described below under stop end fixing.

Step 11 When the installation is complete, remove the plastic retaining bands from the module. This is carried out with the aid of a sharp knife.

Step 12 The procedure mentioned in steps 5 to 10 are repeated until the area to be lined is completed.  The  final task is to tamp the face of the lining to tighten all the joints, close any small superficial openings  on the face of the lining and to improve the overall appearance. The tamping shall be done using a  wooden Board or plywood kept on the surface to be tamped and then a wooden mallet shall be used  for tamping. Limited force only can be applied while using a wooden mallet and since the applied  force is distributed, extent of force may be described as force generated by a normal human being  using a wooden mallet. Excess force will only cause the mallet to break.

•

Installation Procedure of Pyrofold M modules: The general lining installation procedure of PyroFold M-module is as follows: (i) Remove the thread cover from the stud. (ii) Lift the module and push the module against the backup blanket. (iii) Insert a hexagonal nut into the end of the nut driver and thread the nut by hand on to the stud and tighten. (iv) Remove the nut driver and the collapsible access tube from the module. (v) Pinch the fiber together to eliminate the hole. (vi) Repeat the process until all the adjacent modules have been installed.

(vii) Install batten strips. (viii) When all the modules have been installed, the lining should be tamped out to further tighten all the joints and close any gaps that may exist. •

Pyro-Bloc M & Pyro T Bar corner module See Pyro-Bloc M module Design Manual as attached

and

installation

5.3.4 Ceramic Fiber Blanket Lining. A) Location :

Arch cover plate

B) Procedure : Inner surface lined with Ceramic Fiber shall have Acid Proof Coating. The arch cover is to be lined in several pieces with compression joints between the ceramic fiber linings. For blanket lining, the cold face blanket is cut with excess width so that it can be wrapped over the hot face layer as shown in drawing. The intermediate layers are cut to the exact required width so that the wrap over of the cold face layer would be protruding out and will form a tight compression joint when fixed to the next piece already lined. Also when lining the backup blanket layers, compression joints of 10mm has to be achieved as detailed in the drawing. Care should be taken to ensure that the blankets are tight around the tube sleeves if any. 5.3.5 BRICK LINING A) Location: BRICK & BLOCK: Lower Radiant Section B) Procedure: Lower Radiant Section is lined with a combination of 2 layers of insulating blocks and one layer of hot face insulating bricks anchored to the casing.

The blocks are then laid out starting from one corner. Blocks are supplied in standard size of 1000 x 600mm. The first layer of blocks are cut and laid out in between the anchor plates for b/w. Bricks hooks are inserted through the Cleat slots and kept in position. The gaps between adjacent boards if any and at brick hook locations are filled with block mix (block powder mixed with water to paste consistency). When the second layers of blocks are installed necessary cuts are done on the blocks to allow for the brick hook anchors. The gaps so formed are again filled with the block mix. While laying the second layer of blocks, care should be taken to ensure that the joints of second layer are staggered by a minimum of 50mm from the joints of the first layer. At the top, the blocks are cut tight against the bottom of the shelf plates.

To commence the brickwork, first the corner bricks are laid with expansion joint blanket strip between them. Then the bricks are laid along end wall and sidewalls as shown in drawing using blakite mortar mixed to proper consistency. Mortar joints are between 1.5 to 2mm in thickness (horizontal nominal joint thickness of 1.8mm and nominal vertical joint thickness of 1.4mm). Layer as shown in drawing is followed for each course. In the fourth course on each brick, after marking the anchor location insitu, a small hole of 6mm dia and 35mm deep is drilled and then a saw cut 6mm deep x 6mm wide is made to enable the anchor snug fit with the bricks it is holding. Same procedure is continued to complete the brick work as in drawing. The anchors are located on various courses as shown in drawing. At the top of brickwork and below the shelf plate a folded blanket is introduced to enable the vertical expansion of brickwork as indicated in drawing. While installing expansion joint bricks great care should be taken to ensure that the central joint between the two expansion joint bricks are dry laid and not with mortar to assist movement between them. During brick lining in lower radiant wall, the shelf plate bricks and expansion joint bricks have to be cut / shaped at site as shown in drawings.

General points to be followed for brick work•

Each brick should be checked, prior to installation, for defects, cracks etc.

•

The mortar for bricks is supplied in drums on ready to use wet blend form and would harden when it comes in contact with air. So drums should be opened only when its necessary and required quantity taken out, mixed and supplied to the mason.

•

The layout should be first marked out and expansion joint positions fixed.

•

The brick lining should be in plumb and in straight line.

•

The anchor positions should be properly marked and holes drilled in it. Anchors should not be inserted into the brick by hammering it in. It would create cracks in the bricks.

•

Mortar should be evenly applied over the bricks face. Trowelling excess mortar on the edges should be avoided.

5.3.5 CASTABLE WITH BACKUP BLOCKS: A)

Location

B)

Procedure:

i) ii) iii)

Radiant Floor Transition Floor Bull Nose

As in brickwork, for Castable also blocks are lined initially, with care taken to ensure that adjacent joints are offset by at least 50mm. In case of walls, the blocks are first placed in location and pressed slightly against the studs for making the impressions of the studs on to the blocks. Holes are then drilled into the blocks at these points. After lining the blocks the gaps are filled tightly with block mix and V anchors are installed along with the washer to hold the boards in position. Once the back up lining is completed, formworks are fixed on alternate panels and Castable lining carried out by pouring the mixed Castable into forms. Formwork is removed after 24 hours and curing carried out Panel sizes are determined based on the shuttering dimensions and expansion joint locations in the drawing. At expansion joints, blanket strips wrapped in polythene sheets are placed prior to

casting. The general construction considerations detailed below has to be adhered to strictly. 5.3.6 Castable Lining: A) Location : B) Procedure

Collector, Duct and Stack :

Castable Lining procedure is similar to as explained above. Initially the casing plate is cleaned and side formworks fixed for Castable lining. Mixed Castable is then poured, ramming and then discard the access material from the top of the side forms to attain the casing contour. After lining and once the Castable start setting, the surface is covered with wet gunny bags for proper curing or cover it with polythene sheet properly for self curing. In horizontal position, the castable lining shall be carried in alternate / staggered panels (each panel / segment should not be more than 0.9sq.m area but not larger than 1.44sq.m. Segments shall be made of plywood templates along with the wooden strips, which are useful for construction joints. And templates for curved surfaces shall match the contour of the surface.

Note : ground.

The collector’s duct and the stack are to be lined at

The stack is lined in three parts, circumferentially, by rotating the stack segments. Initially the stack pieces are kept horizontally on supports and side forms fixed. Then the bottom 1/3rd, i.e. from 4 'O' Clock to 8 'O Clock position is line by pouring and ramming. Once the entire segment has been lined at this position, the stack segment is rotated to bring the upper 1/3rd to ground level (i.e. 12 'O Clock to 4 'O Clock position is now in 4 O' Clock to 8 'O Clock position after rotating). Same process as above is carried out to complete the lining activity of the subject segment. The stack is made available for lining in two segments.

SPECIAL CARE TO BE TAKEN ON: (i & ii) Radiant Floor and Transition Floor:

Radiant Floor refractory lining is installed in the end after the completion of arch / wall lining and radiant tube erection. Lining is carried out in-situ. The back up insulation board is initially laid out. Towards the wall side the blocks are laid out tightly against the insulating Fire Bricks already lined on the walls. Next course is then laid similarly. Care should be taken to ensure that the joints are offset by a minimum of 50mm between adjacent layers. Balance layers of blocks are also similarly laid out to complete the back up board insulation. A strip of 19mm thick Cerachem blanket of required width, covered with polythene sheet is laid against the insulating Brick lined on the walls. Side forms for Castable is then laid out in line with the construction joints and alternate panels are poured. After few hours when the Castable has set, the said forms can be removed. Care should be taken to ensure that lining is not disturbed or damaged while removing the side forms. Intermediate panels are then poured to complete the lining of the subject layer. Final layer of Castable is poured similar to the first layer, after ensuring that the joints are offset by a minimum of 100mm between the bottom layer Castable. Relevant drawing gives the necessary guidance regarding expansion joint locations. In case additional construction joints are required, care to be taken to ensure that the joint is 'Z' shaped similar to the expansion joints. The installed Castable can be cured by either intermittent spraying of water or wet gunny bags laid out over the Castable lining.

The bottom nose castable is also to be lined as above described method. Area around De-Cocking connections shall be lined with castable after laying two layers of block 607 as back up. All the expansion joints of floor are to be covered with JM 26 STD brick and mortared one side as shown in the relevant dwg. During castable lining, the instrument connections should be wrapped with Ceramic Fibre Blanket and then covered with

polythene sheet, before pouring the Castable. In case instrument connections are not fitted, a PVC tube of similar diameter is placed in position after wrapping it with blanket to ease removal after casing.

Expansion Joints & construction joints if any shall be staggered as shown in drawing. At the bottom of the wall lining a recess of 38mm is kept to enable the floor lining to extend inside the wall by 25mm. The installed Castable to be cured by using wet gunny bags or intermittent spraying of water. (iii)

Bull Nose along Radiant wall (Radiant to Transition):

The lining is carried out in-situ after erection. As in walls initially the blocks are lined and secured in place with washer & 'V' anchor. The watertight formwork is then fixed, properly supported from the bottom. Castable is then poured from the top. Formwork can be removed only after a minimum of 24 hours as it is in overhanging position. The convection section is lined at ground in shop.

As in other areas, initially the blocks are lined and then secured with 'V' anchor. Castable lining is carried out by pouring castable into watertight side forms in alternate panels. After removing the side forms once the castable has set, in-between panels are cast after an interval of one day from the previous casting. Pockets, as shown in drawing, have to be left for intermediate tube supports. In ETS the next row of tubes shall be filled with castable. Instrument connection nozzles are wrapped with Ceramic Fibre Blanket 19mm thick compressed and covered with polythene sheet prior to pouring. (iv)

:

Collector Duct

In ducts Castable lining as explained above has to be carried out. Ducts should be lined at ground level by rotation.

General instructions for Castable Lining Work Planning Work planning is very important for a smooth and quality lining work. The day prior to the planned casting activity, all parameters associated with lining activity should be checked for adequacy like cleanliness of the casing, availability of sufficient Castable material and potable quality water at site, manpower etc. Ambient Conditions Castable lining is ideally carried out in temperatures between 10 to 32°C. If the ambient temperature exceeds 32°C,the mixing water can be cooled down by using ice made of potable quality water. A rough shade over the castable lining area shall also help in preventing direct sunlight falling on wet installed castable. In hot weather direct sunlight shall be avoided on out side casing where castable refractory is applied.

Surface preparation The work surface shall be completely free of dust, scale, oil, water dirt and loose foreign material. (Wire brush cleaning to be applied).

Formwork Formwork should be constructed from strong materials. Generally 3/4 inch plywood or steel forms are favored for this job because of their inherent strength and non-absorbent nature. The surface of the formwork must be cleaned, lightly and thoroughly oiled or greased to facilitate easy removal from the face of the casting after completion of lining activity. The surface of the formwork should be uniform and smooth to give a goods surface finish to the casting. It also aids in formwork release. Formwork must be as watertight as possible, so all joints and holes must be sealed. The formwork should also be properly supported, especially in the case of vertical wall casting, to prevent collapsing of the system when loaded with wet concrete. Water: The water used for mixing should be clean and of potable quality, of low acidity, free from salt, sugar and other foreign matter. Should quality of water be uncertain, it should be analyzed and ensured that it complies with the following specification advised by Thermal Ceramics.

PH Ca2+ Mg2+ K++Na+ ClFe3+ SO42-

: : : : : :

6.5 to 8.35 < 300 PPM < 300 PPM < 150 PPM < 200 PPM < 300 PPM : < 200 PPM

Residue after Evaporation at 180 Dg C

:

1500 PPM

In case the available water does not conform to the above specification, de-mineralized water should be used. The amount of mixing water added to the Castable plays a very important role in the strength and quality of Castable. Hence the ratio of mixing water has to be determined initially using the date provided in the date sheet as guidance, it has to be adhered to strictly. Water amounts shown on the back of the monolithic bags are intended as a guide only. Actual amounts will depend upon field conditions. Mixing – Mixing combines the dry materials and water into a homogenous mass. Mixing must be done in paddle type mixer of sufficient capacity to ensure through mixing of the Castable. The mixer and tools used in casting must be clean. Some substances like lime or Portland cement, found in dirty mixers can cause flash setting or otherwise lower the ultimate strength of the Castable. The mixer should also be washed periodically during the course of mixing to prevent buildup of material. Do not mix more material than can be placed within 15 minutes from the start of mixing and do not combine different type of materials. In no circumstances should be Castable be remixed after they have stiffened or started to set. The moisture content in Castable is critical for dense concretes where maximum strength with optimum density is required. Insulating concretes by nature are weaker than dense concretes and thus it is important that they too should be mixed properly with correct amount of water.

Too much water will reduce density and strength while too little water will decrease the yield and may cause difficulty in proper placing of Castable / working with the Castable. Because of the possibility of segregation of the various components of the Castable within the bag during shipment, it is essential that only full bags should be used for mixing. If any a small quantity of material is required for some reason, then the full be bag should be dry mixed and then required material from it taken for mixing. The balance should be packed in bags immediately for further use preferably in the next immediate requirement. To mix the Castable, it is recommended to add first 80 ≅90% of the water specified by Thermal Ceramics Data Sheet and then to gradually add water till required consistency is obtained. Guidance for consistency is as follows: -For insulating Castable water addition should be as specified in the latest technical data sheet of the Castable. For dense Castables the water quantity will be the minimum required to install the material properly. Ball in Hand test can also be used to gauge the consistency of the Castable.

Add the minimum quantity of water in the mixer while mixing the Castable and then scoop out sufficient mixed Castable in the palm of the hand to make a ball. The ball is then bounced in the hand. Too dry a mix will break up and too wet a mix will slump through the fingers. If the bouncing imparts a wet glistening look to the ball without any appreciable transfer of water and cement to the palm, the water quality is the optimum. The mixing time is normally around 3 minutes and should be controlled Excessive mixing may lead to crushing of aggregates and changes the properties of the materials.

The discharge gate should be cleaned out after every mix to prevent build-up of old material in the region. At the end of every day or at the end of casting activity on each working day, the mixer shall be thoroughly cleaned. Similarly the mixer should be thoroughly cleaned with water whenever a different type of Castable is mixed.

Placement: The Castable shall be installed immediately after mixing. The aim should be to position and consolidate freshly mixed material within 15 minutes of it leaving the mixer. The location of mixer machine and manpower required to shift the mixed Castable and for placing should be adequate for fast placement. This has to be taken care of while planning the Castable lining. Also the time between pouring of consecutive batches must be such that the setting of the first batch should not begin before the second batch is poured. The Castable must be installed in a manner, which minimizes material segregation. It should be poured slowly into position, taking care that every undercut or profile is completely filled up and the lining is devoid of any air pockets. For insulating Castables rodding or tamping is sufficient to remove voids and to consolidate the material without excess compaction. Excessive rodding is also not advisable for lightweight Castables as it will crush the materials and increase the density. Striking the formwork from outside with hammer will also help to avoid formation of air pockets. Once the installation has started, it should proceed without interruption until the lining of the part or section concerned is completed. In case of any unavoidable interruption in lining activity, the wet edge of the lining shall be cut back at right angle to the surface of lining and all material ahead of the cut shall be removed and discarded. Each batch from the mixer shall be installed so that the full thickness of the lining is produced, rather than building up

the thickness in layers. When doing vertical casting as in walls, the Castable shall be spread evenly along the length of the shuttering and tamped in order to obtain a homogeneous lining. Joints Construction joints are designed the break the job up into conveniently sized panels. Adjoining panels are cast against each other without leaving any gaps using the set face of previously cast section as the formwork edge. Typical joint details are as shown in relevant drawings. At expansion joints, Ceramic fiber blanket strips covered with thin polythene sheet (to prevent absorption of water) are used. Finishing When finishing the exposed surface of the refractory Castable lining, it is important to avoid smooth / excessive trowelling of the surface. Excessive working draws water to the surface along with the fines and cement binder and produces a fine finish rich in cement which is easily dislodged by peeling on curing and certainly on exposure to elevated temperature / alternate heating and cooling. Thus the lined Castable surface only needs to be leveled with a screed or wood float and not to be trowelled to a smooth finish. Curing Curing prevents the loss of moisture from freshly cast refractory concrete. Loss of water from the surface of the cast before the bond is fully hydrated results in a weaker lining. To prevent this, various methods of moist curing can be used. Formwork should be left in place for a minimum of 24 hours and exposed refractory concrete either sprayed with water, covered with plastic sheeting or with wet gunny bags. This is called moist curing. Moist curing can start immediately after the initial setting when the lining surface is hard enough to prevent impinging water from washing out the surface cement and shall proceed for a minimum of 24 hours. During the curing process the refractory lining and casing temperature shall be maintained between 10 to 32°C, if the lining is done in open air, the surface of lining should be

protected from direct sunlight by shading until the wet curing process is complete. After the initial 24 hours of moist curing, formwork can be stripped away, being careful not to damage the lining as this could possibly occur. A further 24 hours air curing should be allowed before the lining is fired to further increase the final strength. Refractory lined equipments or panels should not move at all from its place of lining on site, until the curing operation (wet curing + air curing) is completed. Besides general guidelines regarding the castable application shall be followed as detailed above. 5.4

Equipments, Tools and Tackles for Lining Installation: Welding • • • • • • •

Welding equipment suitable anchors: Angle Grinder with discs Wire Brush Measurement Tape Chalk Lines Punch Hammer

for

welding

of

various

Ceramic Fiber / Module Lining • • • • •

Measurement Tape Long Bladed Knife Hack Saw for cutting SS Tubes in Modules Lubricators / Slip Plates Socket with extension arm for tightening nuts to fix modules

• •

Hand Tools like Screw Driver, Pliers etc. Tamping Tool (small flat piece of ply wood / wood or expanded metal Approx.300 x 250mm with a handle for tamping modules after installation.

Castable Lining: • Paddle Mixer • Water Tank • Wooden tray with GI or Aluminium facing • Rubber / GI Buckets for transporting mixed castable. • Formwork, Supports and hand tools for fixing formwork / supports. • Pans • Tamping Rods • Electric or Diesel Vibrator • Thermometer • Trowel • Gunny Bags for curing • Wooden Hammer • Binding wire. • Spirit Level / water level. • Measuring Jar • Moulds for sample preparation. Insulation Block and Brick Lining: • • • • • • • • • • •

Measurement Tape Drill Machine with 6mm & 12mm drill bits for bricks and blocks Hand Saw for cutting Pans for mortar / block mix Heavy Duty Drill Machine with spatula for mixing mortar Wooden / Robber Hammer Plumb Bob Trowel Straight Edge Angle Water Level

5.5

Drying Out The process of curing of castable does not end with wet curing. After wet curing for 24 hours, the castable should be air dried for a minimum of 24hours. Subsequently it has to be dried out gradually by using Flue Gas to remove the water content inside the castable as detailed in Ciria Doc. No. 2051522. Drying out has to be done meticulously and carefully.

6.0 QUALITY ACTIVITY:

ASSURANCE

PLAN

-

SITE

INSTALLATION

A successful refractory lining owes equally to good application practices as to the quality of material. As refractory linings are applied manually, it is essential that the applicator should be aware of the various quality control requirements and its impact on the life of installed linings. Thus it is advisable that the applicators are tested to check their awareness of the various requirements and given proper instruction on good working practices. Equipment's used for the various lining activities should be thoroughly checked to ensure that they are in proper working condition before they are brought to site. Proper quality control of installation can be segregated as • Installation Pre Cautions • Inspection and Test Plan Installation Pre Cautions: Only sufficient quantity of the correct type of material should be brought near the equipment to be lined, prior to lining activity. Storage requirements and precaution against inclement weather should be met at the installation site for the material stocked.

Care should be taken while shifting the material to avoid damages. Different type of blankets and boards should be stored separately to enable identification at work site also. Installers should be properly instructed by qualified persons prior to all types of installation activity on good working practices and the requirements of the job. While mixing mortar for brickwork only sufficient quantity should be mixed. In case of any excess the same should be covered with a thin layer of water on top to prevent contact with air. The same may be drained off prior to use of the mortar. All equipment's and hand tools should be properly cleaned at the end of working shift. Batch No. of castable used should be noted down along with the location of installation of castable. Inspection and Test Plan for Site Installation Activity Anchor Welding Anchor welded to the casing must be securely attached without any weld undercut. Any anchor properly welded shall be capable of withstanding being bent upto 15 degrees from its initially welded plane to the direction o greatest resistance and back without evidence of any weld failure. The anchor weld should be inspected by hammer test wherein striking of the anchor would give a good ringing sound when hit with a hammer. The inspection of anchors can be random. Visual inspection of welding is also done.

Castable Lining: The main objective of physical testing of samples made at site is to assess and judge the quality of installed lining to

some extent without disturbing the lining. Thus the essence of sampling is to ensure that the sample represent the installed lining in all aspects, including the material batch, method of installation etc and is marked properly to correlate the sample to the installed portion of the unit. Sampling for application by casting: One sample per section of the lining for each quality and batch of castable being installed is made during the actual installation. Each sample consists of 3 nos. 50mm ± 4mm cubes, which are cast in metal moulds. The metal moulds are cleaned, slightly oiled and kept ready for sampling. When the installation work / castable lining is ongoing the cubes are cast with the same material. The cubes are then cured, carefully coded and marked. The codes are then mentioned on the lining drawing to indicate the location where the parent material, from which sample was cast, is lined. The batch number of the castable is also noted while sampling to enable correlation of the sample with the batch of the material. The cubes per batch of Castable are then kept together and randomly 3 cubes are selected for testing. 3 cubes per lot (supplied batches of each type of Castable material) of Castable material are then sent for testing (Bulk Density and Cold Crushing Strength). The cubes after wet curing of 24 hours are allowed to air dry for 24 hours before being sent to testing to an approved laboratory or the laboratory specified by the customer/client. The cubes are tested for bulk density and cold compressive strength after oven drying at 105°C, B.D. as per ASTM C 134 & CCS as per ASTM C 133 standards. The results are then compared with the acceptance criteria with an additional tolerance of 10% of the material. Ie for Cold Compressive strength, the permissible value shall be the minimum value as per acceptance criteria less 10% and no limit for the maximum value. Similarly for Bulk Density, the permissible value shall be the maximum value as per acceptance criteria + 10% and no limit for the minimum value. Thus permissible values are

Bulk Density : Value + 10%) Cold Crushing Strength : Value – 10%)

Max

of

(Acceptance

Criteria

Minimum (Acceptance Criteria

In case of any significant variation in test results, another set of 3 bars from the same lot is sent for testing. All other sample shall be preserved with their tag nos. for future use if any. An inspection checklist as detailed below shall be used at site to ascertain the quality maintained during installation of materials.

Cracking Heaters

EIL Job No. LHT Job No. Ciria Job No. Page Ciria Doc. No.

:

6569 6-2426

:

199

:

2 of 29

:

: 199-1502

Cracking Heaters

EIL Job No. LHT Job No. Ciria Job No. Page Ciria Doc. No.

:

6569

:

6-2426

:

199

:

3 of 29

: 199-1502

Cracking Heaters

EIL Job No. LHT Job No. Ciria Job No. Page Ciria Doc. No.

:

6569

:

6-2426

:

199

:

4 of 29

: 199-1502

Cracking Heaters

EIL Job No. LHT Job No. Ciria Job No. Page Ciria Doc. No.

:

6569

:

6-2426

:

199

:

5 of 29

: 199-1502

Cracking Heaters

EIL Job No. LHT Job No. Ciria Job No. Page Ciria Doc. No.

:

6569

:

6-2426

:

199

:

6 of 29

: 199-1502

Cracking Heaters

EIL Job No. LHT Job No. Ciria Job No. Page Ciria Doc. No.

:

6569

:

6-2426

:

199

:

7 of 29

: 199-1502

Cracking Heaters

EIL Job No. LHT Job No. Ciria Job No. Page Ciria Doc. No.

:

6569

:

6-2426

:

199

:

8 of 29

: 199-1502

Cracking Heaters

EIL Job No. LHT Job No. Ciria Job No. Page Ciria Doc. No.

:

6569

:

6-2426

:

199

:

9 of 29

: 199-1502

Cracking Heaters

EIL Job No. LHT Job No. Ciria Job No. Page Ciria Doc. No.

:

6569

:

6-2426

:

199

:

10 of 29

: 199-1502

Cracking Heaters

EIL Job No. LHT Job No. Ciria Job No. Page Ciria Doc. No.

:

6569

:

6-2426

:

199

:

11 of 29

: 199-1502

Cracking Heaters

EIL Job No. LHT Job No. Ciria Job No. Page Ciria Doc. No.

:

6569

:

6-2426

:

199

:

12 of 29

: 199-1502

Cracking Heaters

EIL Job No. LHT Job No. Ciria Job No. Page Ciria Doc. No.

:

6569

:

6-2426

:

199

:

13 of 29

: 199-1502

Cracking Heaters

EIL Job No. LHT Job No. Ciria Job No. Page Ciria Doc. No.

:

6569

:

6-2426

:

199

:

14 of 29

: 199-1502

Cracking Heaters

EIL Job No. LHT Job No. Ciria Job No. Page Ciria Doc. No.

:

6569

:

6-2426

:

199

:

15 of 29

: 199-1502

Cracking Heaters

EIL Job No. LHT Job No. Ciria Job No. Page Ciria Doc. No.

:

6569

:

6-2426

:

199

:

16 of 29

: 199-1502

LARSEN & TOUBRO LTD.NEO STRUCTO CONSTRU CTION LIMITED

Cracking HFurnace eaters RevampProjec t Job I.P.C.LO. C. L.VPanipatadod ara GUJARATHariy ana, INDIA

EIL Job No.

:

L&HT Job No. Ciria Job No. Page

:

Ciria Doc. No.

65569 3000262426

:

205199

:

17 of 29

205: 15231991502

LARSEN & TOUBRO LTD.NEO STRUCTO CONSTRU CTION LIMITED

Cracking HFurnace eaters RevampProjec t Job I.P.C.LO. C. L.VPanipatadod ara GUJARATHariy ana, INDIA

EIL Job No.

:

L&HT Job No. Ciria Job No. Page

:

Ciria Doc. No.

65569 3000262426

:

205199

:

18 of 29

205: 15231991502

LARSEN & TOUBRO LTD.NEO STRUCTO CONSTRU CTION LIMITED

Cracking HFurnace eaters RevampProjec t Job I.P.C.LO. C. L.VPanipatadod ara GUJARATHariy ana, INDIA

EIL Job No.

:

L&HT Job No. Ciria Job No. Page

:

Ciria Doc. No.

65569 3000262426

:

205199

:

19 of 29

205: 15231991502

LARSEN & TOUBRO LTD.NEO STRUCTO CONSTRU CTION LIMITED

Cracking HFurnace eaters RevampProjec t Job I.P.C.LO. C. L.VPanipatadod ara GUJARATHariy ana, INDIA

EIL Job No.

:

L&HT Job No. Ciria Job No. Page

:

Ciria Doc. No.

65569 3000262426

:

205199

:

20 of 29

205: 15231991502

LARSEN & TOUBRO LTD.NEO STRUCTO CONSTRU CTION LIMITED

Cracking HFurnace eaters RevampProjec t Job I.P.C.LO. C. L.VPanipatadod ara GUJARATHariy ana, INDIA

EIL Job No.

:

L&HT Job No. Ciria Job No. Page

:

Ciria Doc. No.

65569 3000262426

:

205199

:

21 of 29

205: 15231991502