Room temperature vulcanized silicone rubber compensator design and manufacture process

Rubber compensator has good characteristics of corrosion resistance, anti-vibration, a large compensation quantity, high pressure intensity compensation, market demand is huge.

Gas turbine power plant A shortfalls in a gas turbine start intake pipe position has a rubber compensator, due to careless when overhauling burst damage, need within 10 days of maintenance cycle rushed the new added installation. The product size is 990 * 650 * 290 (mm), the working medium is the clean air pressurization filter, working inner pressure is not greater than 0.25 MPa, the working temperature is less than 120 ℃, and the working life of the product is more than 3 years. The company promises to develop qualified product to the user on time, the product will face product working pressure is higher and the development cycle is very short and other problems. This paper reviews the design and development process of the product, the introduction of room temperature vulcanized silicone rubber compensator design and process technology.

Product development plan
Usually non-metallic fiber fabric compensator working pressure is less than 0.01 MPa, the rubber compensator working pressure relative to increase 25 times, must use the new material and product structure. Bearing strength of rubber compensator is dominated by enhanced fiber or fabric layer as a skeleton materials, rubber materials and organic polymer substrate materials can be considered as composite products, interlayer thickness is thin, the colloid shop because of its high elasticity, contribution to the strength of the composite material component can be tentatively approximation, strength calculation of the product only for its design and calculation of skeleton material mechanics performance data. Considering the urgency of the product manufacturing cycle, to make the most of the company’s inventory non-metallic fiber fabric compensator is the main raw materials to the new product of rubber compensator, at the same time because the company doesn’t have high temperature vulcanization tank (or large size high temperature plate vulcanizing machine), it ‘s late for the temporary production or purchasing the procurement of rubber molding equipment, temperature vulcanized rubber materials can only be considered as the rubber material. The final design scheme is the base material chooses 106 room temperature vulcanized silicone rubber, organic tooling and choose simple steel sheet forming internal model, rubber skeleton material selection is rubber coated fiberglass cloth of thickness 1.2 mm and 0.2mm double-sided rubber coated fiberglass cloth, and 40 mesh 316 stainless steel wire mesh, etc.

Though the strength of 106 room temperature vulcanized silicone rubber is lower than high temperature vulcanization rubber material, but can not use any mechanical equipment and high temperature vulcanization molding mould, only using thin plate with simple internal model can be formed, which can significantly save the time of manufacturing high temperature vulcanization molding.

To clear the strength of the material performance, the relevant material performance test sample was sent to the Technical quality inspection institution, obtaining performance test report; And immediately design the room temperature vulcanization simple internal model and compound colloid sample test fixture.

Product design calculation
Rubber compression strength calculation formula of compensator [1]
1
Type of – rubber compensator theoretical burst pressure, MPa; – the number of unit length cord arrangement, counts/cm; – single cord minimum tension, N/count; – the product diameter, cm; – the number of fabric layer; – the skeleton strength loss correction coefficient, generally take 0.7 ~ 0.9; – comprehensive correction coefficient, when D≥50cm, usually take 0.9.

The calculation of rubber compensator skeleton material design layer
From the material performance test report provided by the Quality inspection institution:
1.2 mm thick rubber coated fiberglass cloth of unit length minimum tension = 978 N/cm;
0.2 mm thick double-sided rubber fiberglass cloth of unit length minimum tension = 368 N/cm;
Computing framework material layer formula:
2
Skeleton material per unit length minimum tension, take =+=1346 N/cm,Take the design input pressure P = 0.25 MPa; Because of the performance test report by direct reference to the quality inspection institution, therefore, take C = 0.9 , According to the product the perimeter converted to the equivalent diameter of the products is: D = 99 ㎝, C’ = 0.9 .
According to the calculated formula ⑵: I = 2.27 (layer).
Skeleton material design means the product layer select each with 3 layer of 1.2 mm thick rubber coated fiberglass cloth and 0.2 mm thick double-sided rubber coated fiberglass cloth can meet the design requirements of the product working pressure is less than 0.25 MPa.
According to = 3 put it into the formula (1) :
3

Consider the product to leave some redundancy design safety pressure margin
Add 1 layer of 40 mesh 316 stainless steel wire mesh as skeleton material, according to the experience, the unit length minimum tension of 40 mesh 316 stainless steel wire mesh F=300 N/cm, which can increase the product load about 0.025 MPa pressure; Consider the room temperature vulcanization glue organic silicone rubber matrix material tensile strength, look-up table is 4.5 MPa [1], if the thickness of rubber layer is about 5 mm, relative to the product diameter = 99 cm rubber compensator, and can increase the product structure bearing 0.045 MPa pressure value, integrated to calculate the actual product design working pressure:
P2=0.33+0.025+0.045 =0.4(MPa)
P2 compared to the design input pressure indicator P , which left 60% of the strength margin, indicating that the product design is still relatively reliable.

The final design scheme
The rubber compensator products using 3 layer rubber fiberglass cloth of 1.2 mm thick and 3 layer double-sided rubber fiberglass cloth of 0.2 mm thick, add 1 layer of 40 mesh 316 stainless steel wire mesh as skeleton material, using the 106 room temperature vulcanized silicone rubber for organic substrate adhesive material, the whole thickness of rubber layer is about 5 mm, with skeleton material thickness, thickness of the whole product is about 10 mm.

Product process development
Product drawings (figure 1)
Figure 1
Figure 1 Gas turbine start pipe rubber compensator product design

The internal mold of preformed product molding simple steel sheet
2.0mm thick A3 steel plate as shown in Figure 2 into two templates, and then bending into a cylindrical, both ends with M8 × 30 bolts fastening.
Figure 2
Figure 2 Internal mold design of simple thin steel sheet forming

Skeleton material of cutting reinforced fiber fabric layer
Cut 1.2 mm thick rubber fiberglass cloth into a strip of cloth 9300 mm * 340 mm; At the same time, cut 0.2 mm thick double-sided rubber fiberglass cloth into two pieces of strip cloths of 6500 mm * 340 mm and 3500 mm * 340 mm; Cut 1 layer of 40 mesh 316 stainless steel wire mesh into 3100 mm x 320 mm long. Remove the moisture in the electric oven for hearing dry.

Glue preparation
Separate 106 room temperature vulcanized silicone rubber to A, B, C components in accordance with the provisions of the proportion of weighing 3700 grams, Stir evenly

Cover molding
Figure 3
Figure 3 The picture of rubber compensator tape after products molding

Cover a layer of PP plastic film as the release layer on the surface of the assembled simple steel plate internal molding; The stirred batch of 106 room temperature vulcanized silicone rubber colloid was evenly coated on the internal molding surface, to dry for several hours; Coat the mixture of glue on the cut reinforced fiber fabric covering layer evenly, and immediately flattened on the molding of the inner surface of the mold, first wrapped in a thick layer of 0.2 mm double-sided rubber coated fiberglass cloth, and then 1.2mm thick dipped glass fiber cloth filled with three layers and wrapped a layer of 40 mesh 316 stainless steel mesh, 2 layers of 0.2mm thick double-sided coated glass fiber cloth wrapped continuously; remove the bubbles from the rubber layer with scrapper during the whole process; Finally, the remaining silicone rubber mixed colloid evenly coated on outer layer of product; and cover a layer of PP plastic film as the release layer on the outside surface, and then cover with two layers of thick cardboard; and then wrapped with acrylic long rope tightly, with contact pressure, so that the product can be compact after vulcanization molding.

Room temperature vulcanization
To ensure that the product has good strength, ring construction forming stand for the workshops, to ensure that the room temperature curing time is greater than the specified process time.

Demolding and dressing
Products which meet the requirements of room temperature vulcanization time, dismantle the long rope of the outer layer, peel the thick cardboard and PP plastic film, remove the molding of the internal model of the connecting bolts, remove the shape of simple thin steel plate mold, strip the product carefully; Prepare 190g 106 106 room temperature vulcanized silicone rubber, repair rubber tire inside and outside the surface of the bubble defects and uneven place, after waiting for several hours at room temperature vulcanization again for final assembly.

Assembly finished products
For the inspection of silicone rubber ring product size and appearance, after meeting the requirements of the drawings, the steel flange is loaded into the rubber compensator products at both ends, after clamping the pressure plate, with electric drill with bolt holes, install M12×50 stainless steel bolts; after the completion of the assembly, cut off the outer ends of the excess rubber ring with waste side; and then use the hydraulic press to preload the rubber compensator product to the installation size, and install the positioning flat rod.

Inspection and test
Inspect the rubber compensator assembly product, and test the pressure performance of products in the same period by the same process, the product samples were fitted with test fixture clamping, pressurized to 0.3 MPa with air pump, 30 minutes of holding pressure, no obvious escape of bubbles and leaks by checking of soap and water, qualified delivery.

Conclusions
This organic room temperature vulcanized silicone rubber compensator, on the basis of relevant professional experience, from the site survey the original size, the early stage of the preliminary planning design, rushed material performance test samples, test the performance index, confirm product design drawings, design schedule of simple interior steel mold, molding, products design rushed colloid sample internal pressure test fixture, to complete the development of samples, product inspection and testing, qualified product delivered to the user scene, to help users solve the urgency, on time with good quality to meet the requirements of the users. This product has been used for more than eight years and is still intact. This also fully proves that the rubber compensator product design method is correct, adequate safety margin, manufacturing process is applicable, the development of efficient, fully realize the requirements of fast and provincial, for the future technical research work has accumulated valuable experience.

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pdfRoom temperature vulcanized silicone rubber compensator design and manufacture process.pdf

Installation position of fabric expansion joints in CFB boiler

Due to the characteristics of circulating fluidized bed boiler, several large parts have each fixed expansion center, such as the hearth, tail shaft flue, cyclone separator, so the two connected parts should be connected with expansion joint. The service life of fabric expansion joint is generally about two to three years, the price is relatively more favourable. Now fabric expansion joint is chosen for boil, and the fabric expansion joint is installed in the exit of hearth, the entrance of cyclone separator, the exit of cyclone separator, the flue of the exit of cyclone separator and shaft flue entrance, etc. According to the different size of boil, the quantity of different fabric expansion joint is also different.

The installation requirement of the fabric expansion joint

In the early time of the fabric expansion joint, the supplier supply the goods dispersively, because of the large size of the fabric expansion joint, and it’s not convenient to transport. In the subsequent installation, the user ask for the overall delivery, so it’s easy to install, but also increase the difficulty of casting refractory.

Because the stiffness of the non-metallic expansion joint is poor, the fixed part of the fabric expansion joint can not be taken off during the installation, however, it can be taken off before the trial operation and after the installation. All the parts should be lifted from the installed time. When using steel wire rope to hoist, be sure that the place where the rope is wrapped with rubber or thin iron wrapped, to avoid the steel wire burr scraping the cover of the fabric expansion joint. The T-lifting lug can also be installed on the fabric expansion joint temporarily, this method can guarantee symmetry of lifting without damaging the cover.

Fabric expansion joints can absorb the expansion of the three-dimensional direction, the adsorbed expansion value is different from the different position of installation. So finding the installed part according the drawing at first, and mark the number for each part with the oil plant. Secondly, point out the working direction of the fabric expansion joint from the drawing, since the direction of smoke flowing has been considered in the fabric expansion joint.

There is metal or non-metallic package material on the cover during the delivery. Do not take off the package material from the cover during the installation, because it is to protect the cover of fabric expansion joint. The welding beans from slag and welding , which is with high temperature, once it falls on the cover, it will burn the cover and lead to leakage.

Fabric expansion joint should be delivered reasonably without pry, in case of the damage of the cover. After the installation, be sure that do not damage the the fabric expansion joint when take off the fixed device. When cutting the inside fixed steel plates with the gas cutting torch, the worker must cut from the fixed plate of the weld, because the fixed steel plate is below the stainless steel wire mesh, and it is easily burned. When taking off the outside fixed device, it is not allowed to cut with the gas cutting torch, because the outside is the cover, and it cannot resist the high temperature. The outside fixed device is fixed with screws and nuts, so take the wrench to take the nuts off, remove the screw, and the fabric expansion joint is in free state.

Inspection of fabric expansion joints before operation

After the installation of the boiler, and before the sub-trial operation, the fabric expansion joints should be with comprehensive inspection, mainly to check whether the temporary support fixed parts removed, otherwise it will affect the normal displacement of fabric expansion joints.

Check the fabric expansion joint furnace inside the pillow-shaped sealing material and the skin is intact, to avoid high-temperature flue gas from the internal channeling, burning fabric expansion joints. Check non-metallic gasket and the bolt is tightened to prevent the high-temperature materials from the sealing surface fall on the surface of the cover to damage. After inspection without problem, the boiler is ready to operate.

Sealing is very important for circulating fluidized bed boiler, and fabric expansion joint is relatively weak in the circulating fluidized bed boiler seal , so the installation of fabric expansion joints in the process should be strictly controlled to ensure that the Installation quality for the circulating fluidized bed boiler seal and the boiler will have a good operation.

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pdfInstallation of fabric expansion joint in circulating fluidized bed boiler.pdf

Storage requirements for fabric expansion joints

The storage environment of fabric expansion joint is the same with other boiler equipment, firstly, the ground should be flat, when putting the fabric expansion joint on the ground, the bottom The bottom that mat with sleepers symmetrically, do not contact with the ground to avoid rust corrosion.About the storage of fabric expansion joint, the same type part can be stacked together, different type part can not be stacked because of the flexibility of the fabric expansion joint. Though it is fixed with steel plate and bolt, the size of the stacked parts are different and lead to the distortion, the fabric expansion joint can not be revised finally.

Fabric expansion joints are mainly made of non-metallic materials, there is no hydrophobic function under un-working storage state. So it’s better to choose warehouse for the storage of the fabric expansion joints, if there is no warehouse, there should be good rain protection facilities. About the storage of the fabric expansion joint, should pay attention to fire and away from the fire operation area, be away from a place where corrosion of metal media to prevent the skin burning and corrosion of fabric expansion joint. Most fabric expansion joints work in the state of micro-positive pressure, the leakage and perforation of the cover will affect the normal operation of the boiler.

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pdfInstallation of fabric expansion joint in circulating fluidized bed boiler.pdf

The structure and function of fabric expansion joint

Fabric expansion joint, also named non-metallic compensator, the main function is to absorb the relative displacement of two parts with relative displacement and two with a relative displacement between the parts of the connection channel seal.
The fabric expansion joint consists of non-metallic cover, thermal insulation part, metal flange, rib plate, bolt and stainless steel mesh, ceramic fiber rope or pillow-shaped sealing material. The cover is made of heat-resistant rubber and glass cloth. Different parts of the fabric expansion joints, there are differences in the internal structure, such as the inside of the cover and a layer of PTFE insulation film, the insulation part of the aluminum silicate fire-resistant fiber felt or rock wool ceramic fiber cloth composition insulation, insulated by the aluminum silicate fire-resistant fiber mat, and covered with glass ceramic fiber cloth. The main design parameters of fabric expansion joint :

Design pressure: 0.1 MPa
Working pressure: ≤0.1MPa
Working temperature: 900 ℃ (Short time temperature resistance 1000 ℃)
Working medium: high temperature flue gas

The expansion direction of the fabric expansion joint in three-dimensional direction is different due to the working position of the non-metallic expansion joint. The design of fatigue life of the fabric expansion joint is about 3000 times. The service life of fabric expansion joint is not only concern the material, but also the sealing structure design of the furnace side of the flue gas, and this is proved on the operating boiler.

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pdfInstallation of fabric expansion joint in circulating fluidized bed boiler.pdf

Application prospect of fabric expansion

As a result of fabric expansion joint has its own inherent characteristics, which are widely used increasingly in the gas turbine, thermal power, metallurgy, chemicals, building materials and other industries. Some of the equipment itself configure with non-metallic expansion joint, and will also further promote the development of fabric expansion joints. At present, the fabric expansion joints of the most popular using occasions is a large displacement at high temperature and low temperature vibration, such as gas turbine flue, circulating fluidized bed, entrance and exit of fan. In the low-temperature situations, as the fabric expansion joint benefit the design, installation, replacement. Compared with previous years, under the appropriate conditions, some design institutes, equipment manufacturers and users select fabric expansion joints. With the fabric expansion joints put into operation and fabric expansion joints selection, design, process to further improve. The use of fabric expansion joints will be further expanded.

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pdfCharacteristics and Application of fabric expansion joint.pdf

The key research of fabric expansion joint

In recent years, Fabric expansion joints are in the direction towards high temperature and improve the life of the development. In the power industry, with the development of circulating fluidized bed boilers, the requirements of the expansion joint is higher, expansion of the circulating fluidized bed cyclone generally need to install expansion joints, and the working fluid temperature here has reached about 1000℃. Therefore, high-temperature design of Fabric expansion joints is an important point. But the difficulty of high-temperature fabric expansion joints is less dependent on the choice of non – metallic materials (Resistant to more than 1000℃ non-metallic materials is still quite a lot). The key is to take what kind of structure and make the metal frame at the lowest possible temperature. At the same time, the metal rack should take special structure to reduce thermal stress. According to the success of the experience gained on the gas turbine, a fabric expansion joint of circulating fluidized bed has been designed and has been delivered, can be applied to metallurgical, chemical and other industries of high-temperature smoke duct.

The life of fabric expansion joints has been the focus of the majority of users. As a result of fabric expansion joints in the operation of the stress is less than the metal expansion joint. After adopting appropriate material and reasonable structure, its fatigue life should be better than the metal expansion joint. An important factor that directly affects life expectancy will be the aging of non-metallic materials, this requires further work on material selection. The specific life of the expansion joint may also have to be running time to prove. However, according to the unit on the use of non-metallic expansion joint understanding of the situation, there are many closing to metal expansion joint. Therefore, as long as the proper selection and reasonable process, fabric expansion joint life should be able to achieve the desired effect. It should be noted that the service life of fabric expansion joints and its structural design, selection, processing, installation are very closely related. Some products do not meet the expected life expectancy, most of these relate to this factors.

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pdfCharacteristics and Application of fabric expansion joint.pdf

The basic structure of fabric expansion joint

According to the working conditions of fabric expansion joints, its basic structure consists of four parts (shown as the attached pic): The inside baffle (it can be omitted some time), its role as a thermal insulation material bearing body and to avoid direct airflow scouring insulation material resulting in premature failure of fabric expansion joints; (2) Rack (it can be omitted for some structural forms and certain working conditions), on the one hand, which is associated with the smoke duct as part of fabric expansion joint, on the other hand, it is used as fixed bracket of fabric expansion joint. (3) Insulation material (medium temperature ≤ 150 ℃ can be omitted), it is mainly isolated heat of the rumors to improve the rack and outer cover of the working conditions, at the same time, possessed noise reduction effect. (4) Sealing pressure layer (cover), its role is to seal and pressure resistance. Main structural forms of fabric expansion joint is relatively wide, which can be summarized and divided into A, B, C, D four forms from its characteristics.
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1—inside baffle;2—Rack;3—Insulation material;4一Sealing pressure layer

A type structure. High versatility, easy installation and replacement, good sealing performance, and large absorption displacement (axial and lateral). Two types, A2-type structure is mainly used to install the vertical pipe to prevent water corrosion at the flange.

B-type structure. Axial size is small, displacement amount absorbed per unit effective length is small. Installed in a vertical pipe at the flange is not easy to be waterlogging, and suitable for making negative pressure resistant type. At room temperature conditions, the rack can be omitted so that can reduce costs and installation time. But the device starts frequently and the displacement of the large amount of cases, which be easy to fatigue damage. It is mainly used for the entrance and exit of draught fan. As a vibration damping device, such as for starting frequent and large displacement conditions, in order to avoid premature failure of the expansion joint, special measures should be taken.

C type structure. With a great absorption of lateral displacement and axial displacement of the capacity. At room temperature conditions, the rack can be omitted so that can reduce costs and installation time. However, it consumes more materials (expensive), large size, should not be made resistant to negative pressure type. Its sealing performance can match B type.

D-type structure. Which is a special structure, its basic characteristics and A-type structure the same, but compared with human-type structurethe, installation of fabric of replacement time-consuming is too long. It is mainly used for internal replacement of non-metallic body of the occasion, which are not restricted with the surrounding space conditions reduce the workload of scaffolding system and so on.

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pdfCharacteristics and Application of fabric expansion joint.pdf

Characteristics of fabric expansion joints

Fabric expansion joints (fabric non-metallic expansion joints) as a kind of expansion joint, it has been in the international community for more than 30 years of history. Fabric expansion joints have some unparalleled characteristics to metal expansion joints, and the scope of its application is becoming increasingly expanded, which is one of the the expansion joints.

Compared with the metal expansion joints, fabric expansion joints characteristics are: (1) Good flexibility and no impact on the equipment and system thrust, convenient for pipeline design and improvement of equipment and system security. (2) The unit length of absorption of displacement is large, which can absorb three-dimensional displacement, up to the effective length of 40%; (3)Simple to install, easy to replace, without the need for high-demand, no need to replace the lifting equipment and short required time. Meanwhile, after adaptation of pipe renovation and Pipeline foundation settlement caused by permanent misalignment in Medium or long term working. (4) Adaptability, any shape and arbitrary circumference can be made. (5) Good effect of Vibration isolation and near zero vibration transmission. (6) High temperature up to 1000℃or more. (7) Corrosion resistance, and as a result of thermal insulation measures to avoid the expansion joints on the surface of certain media condensation corrosion. (8) Soundproof and heat insulation.

The shortage of fabric expansion joints, low pressure, pressure within 1 Kg. Resistance to liquid medium technology is not mature.

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pdfCharacteristics and Application of fabric expansion joint.pdf

Installation precautions for fabric expansion joints

The installation of fabric expansion joint is complicated, especially the the above-mentioned power plant with large diameter fabric expansion joint installation is much more complicated.

According to the drawing, connect the movable end of the fabric expansion joint to the comb box of the lower box one by one. Do not tighten the bolts. After the connection, adjust the gap between the joints to ensure the gap is 5mm. Adjustment is completed, confirming that is correct to weld the pipe and and pipe, pipe and comb plate.Adjacent tubes are connected by connecting plates, the connection plate is connected with the bolt at one end (connected before delivery), the another end is connected with connecting tube. Shown as Pic 3, welding with continuous fillet weld, the implementation of JB / T4709 – 2000 Steel Pressure Vessel Welding Rules. Note that the connection between the angle connecting plate and the connected tube is not welded.

Taking the lap joint form for the 3 layers insulation layer during installation, amount of lap is 300~400mm.After lapping, sew the lap joint with stainless steel wire, and pay attention to the installation of insulation layer, do not pull too tight to destroy it. Special attention to install the expansion joint itself up and down caliber inconsistent that the thickness insulation cotton lap joint is too thick, if the overlap is too thick, and it’s inconvenience to operate, so it’s ok to cut the lap, and sew again.it’s ensured that the thickness of the lap shall not be less than the thickness of a single layer of insulation.

The side with stainless steel wire mesh is mounted towards the furnace during the installation of fabric expansion joint. Do not pull the expansion joint cincture too tightly, and pay attention to protect the cover during the installation, in case of Welding spatter and protect the skin from scratches, cuts, and other mechanical damage.

For the large caliber fabric expansion joint, after installation, must pay attention to check the fabric expansion cincture whether there is damage, leakage, and uncompressed; for steel structure whether there is leakage welding; or whether fastening bolts are not tightened.

For the large caliber fabric expansion joint, manufacture individual parts, transport individual parts, and install each part to large caliber fabric expansion joint. Now it’s one of the essential equipment in the power plant.

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pdfDesign of super large caliber fabric expansion joint for power plant.pdf

Design of super large caliber fabric expansion joint for power plant

Fabric expansion joints has been widely used in various industries and fields in recent years. Fabric expansion joint’s structure is simple, easy to install, and with good corrosion resistance.Shorter length can compensate for the larger axial displacement and lateral displacement and angular displacement; itself does not have the displacement caused by the stiffness of the reaction of the output, the requirement of distance between the fixed bracket and load capacity is not high, the safety of the equipment and system has quite improved. Meanwhile with good sound insulation, vibration isolation, thermal insulation function, easy to install and easy to replace. The disadvantage of fabric expansion joint is withstanding lower pressures.The device between the boiler slag well of the dry-type deslagging equipment of the 2 × 660MW generating unit of a thermal power plant and the comb-shaped plate of the boiler lower header box is designed to absorb the expansion deformation of the boiler in all directions and to withstand the maximum working of the furnace pressure. When the vertical expansion of the boiler deformation in the range of ± 10%, should be ensured that its normal use.

Design condition
The device is used for the outside position of the comb-plate of the boiler’s water-wall lower-section header and can withstand the working pressure of ± 9.8kPa in the furnace.There is dusty hot air with a maximum temperature of 950 ℃. Boiler water wall Lower side comb box Outer side position Interface size is 21598 (boiler furnace width direction) × 4460mm (Boiler furnace depth direction).Thermal displacement value of boilers:Direction X (Boiler furnace width direction of the two-way)59 mm,35mm;Direction Y(Boiler Furnace Depth Direction Horizontal Unidirectional)59mm,35mm;Direction Z (Down)465mm.The outer surface temperature of the device is not higher than 100℃, the upper end is the movable end and the bottom is fixed with the H-shaped steel frame.

Design
Since the diameter of the device to be designed is large, but the installation space is small, the fabric expansion joint can meet the above-described displacement amount.The working temperature of fabric expansion joint in the current market is -40~90℃, the working pressure is ±30kPa, it can be used for high dust concentration of cement production lines, metallurgy, power industry, smoke exhaust pipe. This device can be designed as fabric expansion joint.The structure as Pic 1.
2016121201
Pic 1 Simplified diagram of super large fabric expansion joint
1. Upper end plate pipe
2. Insulating layer fixing device
3. Insulation layer
4. fabric expansion cincture;
5. Platen
6. Firmware
7. Connected tube of the bottom plate
The internal temperature of the fabric expansion joint is higher, and the surface temperature is lower than 100 ℃. So the insulating layer is filled inside. The material of the insulating layer is: stainless steel wire mesh, aluminum silicate fiber blanket and wired ceramic cloth.The heat-resistant temperature of aluminum silicate fiber cloth and ceramic fiber cloth can reach above 1000℃.2 insulation layer is fixed with device to ensure that work does not fall off.
2016121202
Pic 2
The ceramic fiber mat is wrapped with a ceramic fiber cloth and stainless steel wire mesh and sewn together with stainless steel wire to make it integral. The out layer is stainless steel wire mesh, the middle layer is ceramic fiber cloth folder, the inner layer is ceramic fiber mat.
The internal temperature of fabric expansion joint is high, and the high-quality heat-resisting steel is selected for the expansion joint steel structure. The fixing device of the fixed insulation layer is made of high-quality heat-resisting steel and connecting heat-resistant steel.
The diameter of fabric expansion joint is large, and steel with thermal expansion and contraction characteristics, the movable end of the connected tube is fixed with the grooved hole bolt, design the platen connection to absorb the thermal expansion of the non-metallic connected tube, and to avoid the connected tube structural parts to expand with heat and contract with cold, but also to eliminate the installation error, and convenient transportation and easy installation, and convenient to transport, easy to install.
2016121203
Pic 3, The design of active end of connected tube
Silicone rubber has high thermal stability, operating temperature range of 100 to 300℃. Has excellent aging resistance and good process; glass cloth with high strength, dimensional stability and good temperature characteristics; PTFE film has good sealing effect, wired fiberglass cloth has high mechanical properties.
The fabric expansion cincture of the expansion joint: PTFE film, wired ceramic fiber fabric, aluminum silicate fiber blanket, fluorine rubber glass fiber cloth, stainless steel wire mesh, E-glass fiber cloth, aluminum fiberglass cloth,and with glass fiber cloth to cover the edge.
Fabric expansion joint is equipped with a floating inner liner, the liner can effectively block the dust so that the insulation layer is not worn. The inner liner is designed in the form of a segment to absorb the horizontal expansion, and a stainless steel plate is used to connect the plates to each other and fix them with bolts.
The right angel of fabric expansion joint: The bending plate and the two sides of the straight bar is fixed with bolt connection.
2016121204
Pic 4 The design of right angel of connected tube

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