Alleged shut a model to shape the technique that composite material component shapes below the circumstance that craft closes in shade, force plug namely. Mould pressing of SMC, BMC, inject shapes, RTM, VEC waits a technology a moment to be belonged to shut a model to shape craft. As a result of environmental law make and rise to what the product asks make open model shapes composite material is restricted increasingly, made shut a model to shape technical application, promoted the innovation of RTM technology and development especially in recent years.
RTM is to show low viscosity colophony is in close the flow in the mould, soak enhances material and a kind of engineering technology of solidify figuration, belong to the liquid figuration of composite material or category of technology of structural liquid figuration. Its are specific the method is to be in the pattern that has designed, put beforehand via reasonable design, clipping or classics mechanization beforehand the buildup of figuration material, the mould needs to have periphery sealed with close solid, make sure colophony flow is smooth; Shut colophony of ration of the infuse after the model, after waiting for colophony solidify can drawing of patterns gets an expectation product.
This one craft is having a lot of advantage, can use a variety of fiber to enhance material and colophony system, have wonderful goods face. Apply to production high quality the goods of complex form, and fiber content is high, shape composition volatilizes in the process environmental pollution is little, little, manufacturing automation adaptability strong, investment efficiency of little, production is tall. Accordingly, RTM craft is on product of industry of auto industry, aerospace, national defence, mechanical equipment, electron got applied extensively. The chief factor that decides RTM product is a mould, because RTM mould uses shade force plug to be opposite commonly,add up to a method, the exterior quality that thinks method raises standard of yin and yang consequently and dimension precision become the factor of a key that decides product quality.
1) RTM, colophony delivers moulding. This technology comes from polyurethane technology, the mould is shut when shaping, to colophony of the infuse in prefabricated component, bo fine content is low, make an appointment with 20-45% .
2) VARIT, vacuum assists colophony to deliver note model. This technology uses vacuum colophony in inspiratory prefabricated component, also can press colophony at the same time, vacuum is spent make an appointment with 10-28 inch mercuric column.
3) VARTM, vacuum assists colophony to deliver note model. Goods hole is general less, bo fine content but heighten.
4) VRTM, vacuum colophony delivers moulding.
5) VIP, vacuum dipping process.
6) VIMP, law of alterable macerate model. Vacuum of colophony have the aid of or self-prossessed shift, squeezing ramming macerate.
7) TERTM, heat expands RTM. Core material is inserted in prefabricated component, let colophony macerate and taste to mould and figuration heat. Core material be heated expands, squeezing ramming lay up. Use function of this kind of squeezing ramming, combinative appearance pressurization shapes.
8) RARTM, balata assists RTM. In TERTM method need not core material and take the place of with balata. Balata mould impaction shapes article, make hole decreases greatly, bo fine content can be as high as 60-70% .
9) RIRM, moulding of colophony inject loop. Vacuum and pressurization are united in wedlock, to many moulds alternant infuse colophony, make colophony circulates, till prefabricated component is soaked adequately.
10) CIRTM, co-Injection RTM. Inject in all RTM, but the colophony that infuse differs a few kinds, also can use a few kinds of prefabricated component, can use vacuum bag and flexible exterior mould.
11) RLI, colophony liquid dip (ooze) be soiled. In colophony of the infuse inside lower mould, upper mould is enclothed after entering prefabricated component, heat and use hot pressing boiler shape pressure shapes. Heat make colophony viscosity is reduced, liquidity is good, soak easily.
12) UVRTM, ultraviolet ray (solidify) RTM. With SCRIMP law likeness, solidify is fast, must use ultraviolet light source, can pass through vacuum bag of ultraviolet ray and soft qualitative mould.
13) the core technology of VEC of composite material of VECTM fictitious design is to obtain patent “ float to fill mould ” mind. Composite material is installed to the model between the two steeliness pressure vessel that fill fluid, and mould edge container is formed endlong sealed, compressible heat conduction liquid is full of inside container, the liquid is water normally.
⊙ but the requirement according to scale of production, use different data the mould of different class, but utmost ground reduces cost, obtain thereby relatively beautiful economic benefits.
⊙ belongs to method of infuse of the colophony that shut a model, but the oldest rate reduces the harmful composition such as colophony to be opposite the harm of human body and environment, accord with environmental protection requirement.
⊙ uses low viscosity fast solidify colophony, in producing a course, can heat to RTM mould, improve manufacturing efficiency and product quality further thereby.
⊙ is helpful for preparation big in the integral structural member of clean of dimension, complex form, try to please both parties, dimension precision is good, exterior quality is high, mechanical performance is good.
⊙ enhances material to shape beforehand body can ask to have pick according to function to increase, local increase, jumbly increase reach use bury structure of the core that reach clip beforehand, the property that can develop FRP adequately can design a gender.
RTM shapes craft mould technology
1) course of RTM total craft: RTM has 3 main component: 1Raw material system; 2 infuse equipment; 3 moulds system.
2) RTM shapes with mould technology: All RTM product needs to fit the pattern of craft, RTM is not exceptional also. RTM mould can be made with aluminous steel, FRP. Be out of shape not easily as a result of aluminous steel mould but the price is high, do not make the introduction in this. FRP mould basically introduces below.
1, RTM mould type and material
FRP mould is used at RTM, do the mould layer with thick ——7-10mm by general provision board, heat into —— in remove theatrical makeup and costume of fundamental mould surface next core forms interlining structure, mould layer board always thick for 20mm. As a result of this ply insufficient RTM shapes the strength that craft place needs, because this needs,increase further. Profile of box form steel should compare composite material petty gain much, general with consolidate of profile of box form steel.
Proof of FRP mould practice turns over the mould service life that make with inferior colophony extremely short, and also have immediate effect to product quality, so mould surface asks to use be able to bear or endure lukewarm, be able to bear or endure the data that chemistry corrodes will do. The mould cost that make is artificial for the most part, material choice cost has nothing to do with mould total cost almost. Choose system of colophony of vinyl ester mould and gel coat commonly at present, the service life with and prove be had better than material of traditional annulus oxygen and be able to bear or endure lukewarm sex. Occupy foreign data to report, the mould moulding number that makes with colophony of vinyl ester mould already exceeded 18000 much standards second, and still continueing to use.
2, the mould heats
The most resin that is used at industry of glass reinforced plastics has the solidify curve that is in directly with temperature, the means that seeks manufacturing mould to be able to control temperature so has the real sense that comparative, such conducing to optimize manufacturing efficiency. Factual upper mould has temperature every raise 10 ℃ , gel time halve, because this is in environmental temperature (20 ℃ ) below, moulding perhaps time of solidify drawing of patterns needs a part 60 minutes, and in 50 ℃ , same resinite is, moulding is same component, inside 7.5 minutes can drawing of patterns.
Electric heat cloth heats: In RTM mould application heats cloth laid heats in the report of mould memory means already was used a lot of year. Heat evener, mould can easy to do warm up to 100 ℃ above, but the standard applies highest mould temperature to use 75 ℃ .
The liquid heats: The liquid heats is to will heat up installation of loop and cold circulatory system to arrive in appropriate mould structure, can replace report to heat. This still provided a cooling system for the mould. Temperature can pass the circular medium in burying pipe beforehand to control.
3, of the mould sealed
Use at RTM and vacuum moulding (VM) all closing the seal unit that needs to control colophony overflow in modular antrum brim to the model. Below VM moulding circumstance, need seal unit of vacuum of flange of mould of the buy outside adding.
Sealing ring has a lot of different forms, but material of requirement sealing ring is had high temperature resistant and restore consistently to lead. Look organic at present silica gel material is used at colophony of basic model glue sealed it is the most successful. If use is proper, enough provides the service life of above 1000 times.
Passive and sealed: Almost sealing ring of balata of appropriative solid silicon is sectional, the design closes the position to extreme into its “Z” when should shutting a model compressible 1.0-1.5mm. The circumstance make known to lower levels that should not raising a mould to shut modular power arrives effective and sealed, the hardness of sealing ring and the choice that reduce size are crucial. The pressure that just needs because of place is too great, cause a mould easily to be out of shape. General 3-5mm enough prevents mould interface colophony is oozy, achieve thereby effective and sealed.
Dynamic and sealed: Passivity of dynamic form excel is sealed form. It can control sectional change permanently. Graphic representation form its are sectional size variation can be as high as 4mm. This makes perpendicular and sealed contrail can wait for built-in mould flange. Conversely passive and sealed will be “ plasticity is out of shape merely ” is exceeding wear away. Inside of dynamic sealing ring is sectional once pressurization, can offer the adjustment with sealed very good effect. When the mould closes or opening a model, sealing ring is out of shape as really interstitial flexibility, what the “ plasticity that prevented perpendicular direction is out of shape ” is caused wear away.
4, inject mouth
Do RTM to shape the technical personnel of craft takes position of entrance of resinous of injection mould model seriously particularly. Carry out a proof, RTM inject mouth is set in central position (appearance of the antrum that look a model is decided) it is the most reliable.
5, the precision of the mould
RTM mould often is in condition getting power, so for the mould shutting a model to the success, the precision of the mould is one of crucial factors. Control of modular antrum precision is in ±0.2mm is to close the target precision of modular mould, this precision will bring about short of inevitably light blanks and the colophony that cannot foreknow fill up, and moulding dimension out of tolerance. The commonnest is to exceed thick, want to consider material shrinkage parameter inside at the same time.
RTM craft is operated
The operation that RTM craft injects asks to be finished inside 1/4-1/2 gel time commonly, deliver time to be 2-15 minute, deliver pressure to be 0.3-07Mpa.
Colophony transfers pressure is RTM craft in should pilot is main parameter. This pressure is used overcome infuse model antrum and the resistance that soak the place when enhancing material to encounter. Colophony finishs delivered time and systematic pressure and temperature to concern, time weak point can improve manufacturing efficiency. But if colophony flow is too large, glue fluid has not enough time to permeate enhance material, can increase as a result of systematic pressure and cause an accident. Accordingly, ascendant speed is not more than the colophony fluid area that the mould enters in asking to transferring a process commonly 25mm/min. Through observing eduction mouth comes monitoring colophony transfers a process. Think normally, all observation mouths on the mould all have glue fluid to spill over and do not discharge a bleb again, and when the colophony capacity that adds actually and the colophony amount that predict to join agree basically, deliver a process to already was finished namely. Consequently the platoon exports a setting to answer careful consideration.
Colophony choice
The choice of colophony system is the key of RTM craft. Should give colophony to modular antrum inside and make colophony infiltrates quickly fiber its viscosity is for 0.025-0.03Pa•s optimal. Polyester colophony viscosity is inferior, normal temperature issues cold inject to be able to be finished. But, because the function of the product asks to differ, the colophony of different type can be chosen, their viscosity is endless and identical, so pipeline and inject head size all should design the liquidity requirement of appropriate and special component.
The colophony that suits RTM craft has colophony of polyester colophony, epoxy resin, phenolic aldehyde, get together acyl inferior amine colophony.
Enhance material option
Material increases to be able to choose fiber of fiber of fibre glass, black lead, He Fangguan of carbon fiber, carborundum to wait in RTM craft. Breed can need choice weak point to cut fiber, one-way fabric, much axis fabric according to the design, braid, the material such as material of knitting, core or shape beforehand base.
The design of the mould and make
1. The mould makes the choice of environmental requirement and raw material
A. Environment
Environmental temperature: Good range is 25±3 ℃ .
Relative humidity: Cannot be more than 60% .
The workshop that make: The cleanness that should keep taller than product production division is spent with safeguard daily.
B. Material
To the data that this craft place needs we recommend as follows:
① main material
Gel coat: Ccp-071 (have admirable heat-resisting capacity, HDT is 160-173 ℃ )
Mould colophony: RM2000 (fast solidify, create a pattern quickly, low systole, reduce mould cost)
F-010 (colophony of vinyl of annulus oxygen modified, good strength and hear resistance, and low shrinkage)
Exterior felt: 300g/m2
Without alkaline short cut felt: 450g/m2
Light wood: The tigidity that is used at raising a pattern reduces weight
Candle piece: Use at controlling the ply of modular antrum, good ply uniformity.
② assists material
Glue of bottom of agent of polyester sealing of hole, easy burnish, tall smooth gel coat, glass is small bead, all sorts of agent of fourth ketone, acetone, solidify, accelerant, eye count sand paper a certain number of, inject mouth
2. Of skirt edge make
To edge of skirt of mould of light qualitative RTM make especially important, it is to make sure this craft is effective, reliable executive foundation. We go up in the foundation of existing former model, along the product all round do wide by the side of the skirt that is 250mm, making the goal side so wide skirt is to make sure the mould is combining a model is vacuum can give have enough power combining a model, in order to ensure what we inject is successful.
Because this papers a mould to ordinary hand,we can transform our very easily for inject mould.
3. The processing of former model
After been do in mould skirt edge, undertake handling to its with respect to need. Above all corrective the level that its dimension needs to place; Be proper to be being made with product part by the side of skirt radian next pour wine cup.
If our former model attributes local problem, use atomic grey local make level first, it is next by local gush easy burnish glue (particular operation sees later development) .
If the exterior whole situation of our former model is not very good, undertake comprehensive processing with respect to need, the method is as follows:
The sealing of hole of ⑴ former model
Former model surface should keep cleanness, dull, without smeary, candle or other contamination. Face of burnish of 120 eye sand paper is used first before sealing of hole wipe clean. Before use, first the agent of sealing of hole in coal tub sufficient mix is even. Add the solidify agent of 2% next. Use a brush to besmear first agent of Fu sealing of hole, the white cotton cloth with clean reoccupy or paper towel obliterate spare part, notice cloth cannot too thick. Solidify plans succeeding activity after two hours.
Glue of bottom of ⑵ easy burnish is handled
Get the RTM mould face of high quality to ensure, need uses processing of glue of easy burnish bottom on former model, it is had grade flat performance outstandingly, the surface that attainable small hole leads, and can be below wet condition successive spray is laminose the ply that obtains a need.
Particular operation is as follows: First mix of glue of bottom of will easy burnish is even, add 1.5% solidify agent, join the fourth ketone dilute of 15% , the pressure when spray adjusts 15psi, spray gun caliber is 2.0mm, the muzzle when spray is 30cm left and right sides from the distance of former model surface, the rate with floating spray gun wants even. After gush is over 4 hours are used 220 or dry abrasion of 240 eye sand paper removes surface layer, let solvent get better volatilization. In solidify after 6 hours, with burnish of 320 eye sand paper, check whether to have local inhomogenous, the surface is rough whole place, fill to undertaking the 2nd times after this place processing is clean next gush, solidify hind rubs 1500 eye with sand paper, undertake polishing again, attain satisfactory result continuously. The dosage of glue of bottom of general easy burnish is 10m2/gal, ply is controlled in 0.25mm. The former model surface after be being handled with this material has the characteristic with each consistent performance, of the surface bright and clean had spent, the mould that gets with this will be high quality. If have need, can again a tall smooth gel coat comes to spray achieve taller exterior result.
Of 4. lower mould make
After former model is treating our satisfactory rate, make with respect to what begin lower mould. Lay up designs as follows: Gel coat (CCP071) + an exterior felt (F010 colophony) + a 450 G/m2 is short cut felt (F010 colophony) + 5 450 G/m2 are short cut felt (RM2000 colophony) + 2 450 G/m2 are short cut felt (F010 colophony) reach 3/8 inch light wood + 3)
The making move of the mould is as follows:
⑴ . The besmear Fu of agent of drawing of patterns. Have candle of drawing of patterns commonly usedly, agent of liquid drawing of patterns and PVA3 are planted
A. Candle of Paste-wiz drawing of patterns: Clear clean candle of besmear Fu drawing of patterns begins after former model surface, it is 6 times commonly, every all over interval 2 hours, particular mode of operation is as follows: Dip in with cotton cloth first take candle, wipe in the surface forcibly with the means of revolve, back-to-back move uses the candle with identical means redundant purify and the scrape that the cotton cloth when waxing leaves, the interval after finishing undertakes polishing 2 hours with clean cotton cloth. Duplicate identical operation 6 times can.
B. Half permanent liquid takes off X-802 velar agent, the proposal uses agent of S-19B sealing of hole first before use. Mode of operation: Take off Fu of velar agent besmear 5 times. Dip in with clean pure cotton cloth take dose of drawing of patterns but not drippy, agent of drawing of patterns smooth sassafras is in mould surface, form thin only place waits for agent of drawing of patterns to volatilize after thin smooth coating. The attention need not clean operation region too much. After each besmear Fu ends, only place waits for his 15 minutes after dry solidify, reentry issues besmear Fu all right, coating of agent of each drawing of patterns uses different clean cotton cloth independently. If appear fleck, change cotton cloth, ensure to there is the agent of drawing of patterns of adherent excessive on cotton cloth, after last besmear Fu is good, the solidify time that needs 30 minutes. Solidify time is longer, effect of drawing of patterns will be better.
C. If former model is Yakeli's material, we do not suggest to use candle of drawing of patterns and agent of liquid drawing of patterns, choose PVA to regard drawing of patterns as material however, the method that we use spray goes to its very even gush former model surface also can get result of very good drawing of patterns so. Want to notice to adjust the pulverization of good spray gun in the process of spray, let PVA can very layer is very even adhere to former model surface, it is easy to should notice especially part of uncared-for edge part. Suggest usually gush two, principle of pilot of intermediate time interval is before one certain and complete dry.
The spray of ⑵ gel coat
The dosage of gel coat is controlled commonly in 850g/m2, right now ply is between 0.6~0.8mm, gel time control is controlled in 2 hours, gel can bring about gel coat layer too quickly medium porosity is tall. Gel coat divides spray, principle of pilot of two time interval heads a gel coat is complete solidify, it is 2 ~ 3 hours commonly. Control of pressure of spray gun of the ES-100 when spray is in 70psi. Program of spray of mould gel coat: Inspect eject facility above all (ES-100) whether be in kilter, check all encapsulated situation good, pressure adjuster operation is agile.
A, the MEKP of 2% is joined in CCP071 of mould gel coat, mix even.
B, in loading gel coat ES-100 paper cup, adjust pressure arrives 70psi.
The C, distance that makes spray gun and mould surface maintain 300-500mm, first the dig or dig out with a finger or sth pointed on gun head day moves trigger, adjust surface of mould of gun head alignment again pulverization pressure, make jet line achieve optimal status. Notice first the place that gush reachs not easily, for instance the corner of former model surface is mixed orthogonal position, undertake the spray of large area again next, the rate with floating at the same time spray gun wants even. Ask when the first spray the gel coat ply of whole face is evener, the gel coat that the 2nd requirement compares skirt edge share in part of the product on the mould wants a bit thick. The line form of the gush after noticing when spray is pressed in the half position before this, relapse so the spray till the gel coat that finish. At the same time the requirement covers the part establishing a range of margin of mould skirt margin to gel coat. Eject ends instantly rinsing equipment. Find a place for in proper place on the gas source interface that pneumatic drawing of patterns uses.
The shop Fu of ⑶ surface felt
The norms of exterior felt is 30g/m2, colophony is colophony of vinyl F010 mould. In when the 2nd gel coat solidify begins to spread Fu surface felt until sticking a hand not to stick gum, spread the advantage of Fu surface felt to depend on right now: Can raise gel coat and exterior felt layer already stick relay, can better control resinous dosage. It is good that exterior felt can spread Fu in mould surface beforehand, because gel coat still is had,stick certainly right now receive ability, what can spread Fu so is very good, to the butt joint part of exterior felt the requirement undertakes take out orderly the processing of straight edge, the purpose is for can very good butt joint. The weight of colophony of vinyl F010 mould and exterior felt is in than controlling respectively 9: 1. Mode of operation: Brush a few dipping in to take colophony with wool, perpendicular exert oneself to do sth. downward at the surface, from the mould intermediate position begins to go to all around go dispersedly, just soak exterior felt to be a standard with colophony. When paste is made, must notice to eliminate bleb. And the attention is by the side of skirt of the brim establish a face to also need to exterior felt is enclothed on, the purpose is to because contractive problem makes,avoid in the process of the mould that make mould oneself leaves a pattern.
Wait for solidify to use burr of purify of thick sand paper later, carry go bleb, wipe clean surface with acetone next, preparation enters below one process.
⑷ head layer is short the shop Fu that cuts felt
Short the norms that cuts felt is 450 G/m2, colophony is colophony of vinyl F010 mould. Want before paste is made first the fibrous weight that metage has cut down, will control place to use resinous amount from this, general F010 colophony and short the weight that cuts felt is in than control 1.5: 1, right now colophony content is 40% . Make in paste short when cutting felt, wool is brushed use a dot to brush, lest affect fibre glass and bring about bleb and ruffle, do not allow to be in short cut felt to go up to brush colophony back and forth, bleb is eliminated with bristle roller, when roller is pressed from which toward all around diffuse, should note corner position particularly. Short cut felt building when receiving, tear apart with the hand as far as possible, can avoid to appear so the blemish on local intensity. Additional, make in paste enough time should give to eliminate bleb with bristle roller after finishing.
⑸ 5 450 G/m2 are short the shop Fu that cuts felt
When this 5 shops Fu we use the mould resin of RM2000, this resinous advantage is can fast and laminose and the problem that need not worry about systole, the reason depends on the filling that 35 % contain in this colophony system and make its shrinkage very low. The colophony in the operation and fiber weight are in than control in 3: 1, right now colophony content is 50% the left and right sides.
Particular operation is as follows: Divide mould surface into the part of size moderate above all, the 5 layer weak point that need this part place again cut felt to had cut down and metage weight, be in next a level off and the soak with 5 successive felt appears admiral of clean work station face and drive except bleb, again will beforehand the position that the fiber shop Fu with nice dip is in to its, continue roller pressing, drive bleb. Ordinal undertake going down, till the shop Fu is over all fiber, await solidify. The attention must have been handled in the part of the short butt joint that cut felt, get ply as far as possible even laminose.
⑹ light wood
The need before light Mu Zhi spreads Fu first two 450 G/m2 are short cut felt, colophony is F010, the operation is as short as first cut felt identical. When finishing light wood of Fu of the short shop that cut felt, first outline board cuts small into parts, from the mould among begin to go to all around shop Fu, bear fruit with can be being stuck for the standard. To having the mould face of radian, light wood does not have face of strict positive and negative to ask when spreading Fu, go to the lavatory in order to operate for the principle. Also can divide light wood beforehand additionally area cuts down appropriate measure, in the shop Fu is over short after cutting felt, stick light wood directly receive it is OK to go up.
Whether does microscope light wood have after the solidify that finish did not stick strong place, if have,undertake be stickinged afresh receiving, move glass small bead be bored with child get on aperture fill and reentry of pliable processing surface goes next operation.
⑺ follow-up three-layer is short the shop Fu that cuts felt
After light wood has been handled, begin the shop Fu that three-layer weak point cuts felt finally, colophony is RM2000, if preamble place is shown,operate.
Of ⑻ mould strengthen
Because be in when our inject vacuum is additional undertake below the circumstance, pressure of to the mould character place susceptive is not so great, the measure that because this wants only,undertakes to the mould simple strengthening will assure mould itself can. Strengthened material chooses 20mm large compound board, width is 300mm, undertake fixed with wooden bolt in the position of the butt joint, use 5 450 G/m2 next the short paste that cut felt is made on, await solidify.
⑼ drawing of patterns
Come here, the lower mould of mould of light qualitative RTM is made finished, drawing of patterns undertakes handling those who prepare upper mould simply to make later.
5. Stick candle piece
Finishing lower mould after making, prepare to make upper mould with respect to need, this among them the most important process is candle piece spread Fu. Candle piece the ply that ply needs for product place namely, need usually candle piece cent spreads Fu into two, for example the product of 5mm, cent undertakes spreading Fu for 2mm and 3mm, first Bao Houhou. Particular operation is as follows:
Candle piece begin to be extended to four distribution from interface of product part vacuum, the position of vacuum interface is in the place of whole product 1/3 certainly commonly, it is the 2/3 of product length direction with the distance of inject mouth.
⑴ ground floor candle piece spread Fu
Begin from vacuum interface, first candle piece cut 4’’×The diamonds of 4’’ size, when spreading Fu every between the clearance that removed 0.5mm controls, candle piece must stick solid and orderly, all clearance want expedite link. Candle piece shop Fu is controlled to the 2cm outside product edge. Drawknife general is used after ground floor spreads Fu to finish finishing level off, clear clean.
⑵ the 2nd candle piece spread Fu
This one candle piece what spread Fu method with before one is different depend on, must make all candle piece juncture wants rigor, and use pieces whole candle as far as possible piece, candle piece the form that the brim wants to use a tool to shave the margin. Finish all candle in the butt joint so piece later, can shave the surface level with drawknife and won't appear caving place, will assure the making quality of the ply of the product and upper mould with this.
Candle of part of ⑶ skirt edge piece spread Fu
The candle of skirt edge part piece modular process and production shut after can immediate impact arrives successful, because this is a very crucial process. It is with product of a 5mm below for the exemple candle of bright skirt edge piece shop Fu. If pursue,2 are shown.
Explain:
① is the ply of the product, 5mm. Product thick 8mm
Of ② product edge outspread, operate easily when facilitating production. Width is 20mm, ply 3mm. (20mmx4mm)
Passageway of ③ resinous flow, width 15mm, ply 5mm. (15x6)
④ T fluid sealant the position, width 15mm, ply 3mm. (15x4)
⑤ T fluid sealant groove, dimension 10.7mm×5mm. (8x5)
The space of ⑥ air gap, width 10cm, ply 4mm, cent spreads Fu into two, ground floor wants the space of put apart 0.5mm likewise, a whole spreads clothe after.
Fluid sealant of the side outside ⑦ the position, dimension 2.5cm×10mm.
⑧ spreads Fu on ② ③ ④ the candle of a 1mm piece.
Skirt edge candle piece after shop Fu is finished, need comes with clay pliable edge horn.
Of 6. upper mould make
Be over in laid candle piece begin to make force plug, initial need has set the position of the vacuum interface of product part and air gap. Concrete move is as follows:
① is in candle piece on agent of spray PVA drawing of patterns. If preamble place is shown,operate.
The spray of ② gel coat. Requirement gel coat shows isinglass garment for vinyl.
The design of structural layer is as follows: Felt of a surface (30g/m2) + a 450 G/m2 is short the + that cut felt 3 450 G/m2 are short the + that cut felt 3 450 G/m2 are short cut felt
The structure placing core that in local mould place of easy generation metabolic needs to undertake sandwich with light wood increases. Two 450 G/m2 are added again after light wood short cut felt.
③ is in unit process of cargo bandling, after gel coat spray is finished, mix all vacuum interface inject mouth is placed reach the designated position. In solidify of the 2nd gel coat in the begining, to product and skirt edge candle piece partial vacuumize, vacuum is spent very small (make an appointment with 0.5inHg) , as laminose add gradually thick, need what otherwise breaks to increase vacuum to spend, candle does not leave when make sure with this upper mould contracts in solidify piece the surface, the candle of part of the part side can let a mould at the same time piece post it is more good to take a sex, thereby OK and very good maintenance the homogeneity of product measure. The resin that upper mould place uses is F010 vinyl colophony entirely. Operation method and preamble place are narrated identical.
7. later period is handled
Come here, the paste of our mould made a process be finished.
Solidify of the colophony in because the mould is in,making a process is not complete, if throw production immediately, the can serious quality that affects a pattern and life. The solidify after wanting those who have a pattern accordingly is handled.
The method is as follows: Heat treatment has below the temperature of ℃ of 40-50 of use temperature of prep above mould, it is referenced temperature with 60-80 ℃ commonly, the internal stress that solidify eliminates a mould 3 hours and raise resinous solidify to spend, make the mould achieves first-rate performance. After solidify is handled after if on time abundant and OK after setting the pattern a week, drawing of patterns handles again devoted production.
Of the mould that finish hind solidify is OK drawing of patterns undertakes an aftertreatment.
Mould of ⑴ come away, purify candle piece.
⑵ purify candle piece use clean model agent later (CW3000) clean a mould. The need when the attention is operated wears a glove. Water mill can begin after be being cleaned 3 times.
⑶ chooses 600-1000 purpose sand paper, according to mould of product demand burnish. Attention: Burnish when must use pad, such ability achieve anticipated spirit to compile the result. Gasket uses plywood, board, rubber slab to wait commonly, need to be made appropriately according to exercise.
Burnish of ⑷ mould surface begins polishing processing later to 1000 eye. Dip in with cotton cloth take Aqua-Buff 1000w polish to cream with the way that chooses besmear Tu Yumo has the face, use water profit wet. The back-to-back abb that uses a clean, moisture annulus undertake abrade polish. In polishing process, polishing creams likelihood desiccate, after to its mist of exterior gush water makes his new and wet, can continue downward. Arrive when abrade polish appropriate level, bathe is clean mould, change new abb annulus use Aqua-Buff2000 undertakes polishing, operation and 1000w are similar, after polishing ends, the mould can achieve lens side effect. To achieve best result, proposal abb dish rotate speed not under 2500 turn / cent. After polishing is finished, wash mould face clean, natural air.
After polish of ⑸ mould burnish is finished, OK inside and outside two fluid sealant stick receive, and interface of the vacuum on installation, preparation tries a model.
8. tries a model
The process is as follows:
⑴ tries the complete besmear Fu that velar agent must assure before the model, want to do test of drawing of patterns.
⑵ basis the appearance clipping felt of the product, commonly knitting weak point cuts felt and compound felt. The number of plies that spreads Fu is decided by product ply. Local not Fu Tie's position can secure fiber with 3M glue.
⑶ adds up to upper mould to provide, to primary exhausting bringing to bear on by the side of mould skirt (vacuum is spent for 667 millimeter mercuric column) , make fluctuation model compact union, its combine pressure to be able to achieve 1350 kilograms / every meters (edge skirt edge) , consequently need not any clip hold a tool, inside and outside two sealed have airtight effect.
⑷ passes the colophony of inject mouth inject that is located in mould brim, colophony flows along periphery colophony passageway above all, flow to mould center from periphery next, ordinal soak enhances material, can bring to bear on at this moment 2 class vacuum (vacuum is spent for 376 millimeter mercuric column) , in order to reduce the internal pressure of the mould, be helpful for resinous flowing quickly.
After ⑸ waits for product solidify drawing of patterns, examine the case of whole pattern and product. Undertake adjustment when need till satisfaction till. So far, we are whole of the mould make finished.
The blemish with RTM familiar products and settle way
RTM craft can produce high-powered, dimension to be spent integratedly more greatly, high, the product with medium batch. Product measure is in 1500 - 40000, comfortable at RTM craft. Accordingly, RTM is one kind has an outlook very much shape craft. Current, RTM craft applies extensively already at the domain such as building, traffic, telecommunications, wholesome, aerospace. Because this craft is more youthful, there is certain difficulty on the technology, the product often appears a few blemish, the article with respect to RTM goods common flaw undertakes an analysis, in order to offer reference.
1, product surface is local and rough lacklustre
The main reason that RTM product produces this kind of phenomenon is the product spends sticking to mould gently. Feel on the mould with the hand, when feeling these place, feel is extremely rough. After normally the product produces period of time, can appear such problem, need to clean a mould in time at this moment. Use the coarse position on mould of burnish of waterproof abrasive paper above all, dip in with cotton silk next acetone rub-up is whole mould, give a mould dose of besmear Fu drawing of patterns finally.
2, gel coat is corrugate
The main reason with corrugate gel coat is to be in pouring before colophony, solidify of gel coat colophony is not complete, pouring the styrene monomer dissolve in colophony bilges gel coat colophony, generation furrow. Because want to note the following respects when this spray gel coat:
(1) ply of gel coat layer, it is normally 0.3 - 0.5mm or 400 - 500g/ ㎡, its ply can increase when need;
(2) the affiliation that checks agent of accelerant, solidify is measured and mix scale, accelerant and solidify agent dosage must be added sufficient;
(3) wait for gel coat after complete solidify again pouring colophony.
3, leakage glue
The main reason of leakage glue is a mould not close or gaskets is not close after combining a model. Sealing ring should be examined before combining a model in good condition, have wait without break, discover the problem wants to change in time. When combining a model, the mould wants impaction gaskets, pouring when once discover leakage glue,should tighten the bolt all round place of solid leakage glue instantly.
4, bleb
From theoretic analysis, the account that produces bleb has 4 kinds:
(1) reaction of solidify of the colophony inside modular antrum is radiative and exorbitant, solidify time is too short, consequently the gas in modular antrum does not have complete eduction;
(2) the belt when antrum of colophony infuse model enters air overmuch, inside perfusion time cannot all eduction, even bleb is on modular antrum coping all the time, cannot carry its from the colophony that go up and falls go out;
(3) colophony viscosity is too big, bleb cannot spill over from inside the product entirely inside perfusion time. And because colophony viscosity is big, flow is slow, just carried bleb possibly even to product side mid area (when the product is more expensive) , thereby the product after drawing of patterns contains bleb (or hole shape light blanks) more;
(4) the pressure of antrum of colophony infuse model is too great, cause bleb to include in colophony, hard eduction.
Corresponding settlement method is:
(1) proper mix low perfusion uses dosage of colophony solidify agent;
(2) vent is designed on the mould;
(3) the viscosity that 25 ℃ issue test colophony, normally RTM is with colophony viscosity 0.5 - 1.5PaS. If colophony viscosity did not exceed bid, whether to pass with respect to temperature of environment of Lv of take an examination low, if temperature is too low,can be before colophony perfusion proper warm-up amounts to one constant temperature, but temperature chooses to want appropriate, colophony viscosity is too low the mechanical performance that will affect a product;
(4) reduce colophony inject pressure, increase colophony shot, reduce colophony to be in thereby the velocity of flow of modular antrum, increase ooze flow.
5, goods occurrence dry spot
Occurrence dry spot of interior of RTM technology product basically is Bo fine infiltration is insufficient. A certain place of if product of the corresponding period is medium individual product appears dry spot, also may be Bo fine cloth is caused by pollution. Normally goods interior occurrence dry spot also is concerned with colophony viscosity, should be analysed above all so and adjust viscosity; Examine mould flow path whether too grow and too narrow, improve a mould in time, improve makings canal, increase material point.
6, ruffle
The ruffle also is the problem that a lot of RTM products often encounter. Ruffle and corrugate and different, because cloth layer is corrugate,the ruffle is, exterior of the product after drawing of patterns but clarity sees cloth plait, but between cloth plait by colophony cram.
The main reason that the ruffle produces is:
(1) when combining a model, because the mould produces a ruffle to the extruding of cloth layer;
(2) colophony develops cloth when mould midstream is moved crowded be out of shape and produce a ruffle.
Accordingly, product of manufacturing RTM technology should notice operation method combining a model and cloth layer ply. Of operation combining a model undeserved or cloth layer heavy panel is easy cause crapy appearance; Change with be able to bear or endure erode the Bo fine cloth with good sex, shape beforehand blank or knitting are compound felt, reduce inject pressure, reduce colophony to be opposite thereby the brunt of cloth layer.
7, crackle
Domestic RTM craft and foreign photograph are compared, still put in certain difference. The fiber content of product of domestic RTM technology is inferior (make an appointment with commonly 50% ) , and the technology as a result of this craft is immature, the fiber content of partial product distributings inhomogenous, bring about fiber content to spend small part easy occurrence crackle.
From theoretic analysis, the account that crackle produces has two kinds:
(1) goods is inside modular antrum solidify is not complete, even after the solidify after classics is handled, goods interior still is in slow solidify, and resinous solidify shrinkage bigger, such is in in goods the position with fiber small content, bear force carrier intensity is insufficient, as a result of the action of solidify internal stress, goods surface forms crackle;
(2) goods itself solidify is complete already, but because carry the difference in temperature in the process change is big, heat bilges cold shrink, generation internal stress is greater, crackle arises in the weak position of lowest of products fiber content.
Because this answers,according to craft actual condition adjusts craft parameter, raise the uniformity that fiber content and fiber distributing. Want to notice RTM craft uses resinous solidify shrinkage at the same time, colophony solidify shrinkage is big, affect product surface result not only, the internal stress that because solidify is contractive,still can arise increases difficulty of drawing of patterns. Should use low contractive additive at this moment, or with mix model colophony system reduces resinous solidify shrinkage.
Search
Duplicate