CN105642838B - Hub cap fin processing technology - Google Patents

Abstract

The invention discloses a kind of hub cap fin processing technology, it is intended to which distribution of weight is uneven after solving the shaping of hub cap fin, and its drip irrigation device is：By continuous correction and measurement and positioning in manufacturing process, the quality of casting and the standard of size are improved, passes through the effect of drainage trough, in casting process, guiding of the liquid copper alloy according to drainage trough can be made, carry out casting, strengthen the distribution of weight uniformity of casting.The hub cap fin processing technology of the present invention can produce the uniform casting of distribution of weight.

Description

Hub cap fin processing technology

Technical field

The present invention relates to hub cap fin production field, more specifically, it relates to a kind of hub cap fin processing technology.

Background technology

Hub cap fin is also known as propeller hub cap fin, several appropriate blades are installed on conventional propeller hub cap surface and structure Into a kind of propeller energy-saving device, on the one hand absorb the rotating energy of screw current, produce positive torque, on the other hand disappear again The hub whirlpool of propeller is removed or weakened, rectified action is played, so as to reduce hub vortex drag, the efficiency of propeller is improved, due to its structure Simply, new ship and existing obsolete vessel can be easily installed on, is a kind of effective, practical, convenient energy saver, and be advantageous to subtract The exciting force and noise of minor spiral oar.If hub cap fin distribution of weight is uneven, hub cap fin can be caused to be produced in rotary course Unbalance dynamic, because hub cap fin is arranged on propeller, easily cause propeller rotation uneven, and can not eliminate or weaken The hub whirlpool of propeller, existing hub cap fin manufacturing process are difficult to control Mass Distribution, and precision is relatively low, equal so as to influence Mass Distribution Weighing apparatus property and structural strength.Therefore need to propose a kind of new scheme to solve this problem.

The content of the invention

In view of the deficienciess of the prior art, it is an object of the invention to provide a kind of hub cap fin distribution of weight of production is equal Even hub cap fin processing technology is by multiple positioning and uniform to strengthen the Mass Distribution of hub cap fin with the drainage trough of addition Property.

The present invention above-mentioned technical purpose technical scheme is that：A kind of hub cap fin processing technology, Comprise the following steps：

First, the preparation before moulding：Choose in place after under casing, insert mandrel, level is corrected to every 90 ° in 360 ° of orientation；

2nd, striking under casing：Mandrel is in the center of under casing, insert sand mold and pound reality, blown plane with carbon dioxide Firmly, bisector, marking are marked according to blade quantity on circular arc line；

3rd, hub sand mo(u)ld is made：Based on the axle center of mandrel, with reference to the size dimension of hub, measured with model, in hub loam core The fusing point metallic channel that is used to drain lower than copper alloy is bonded on bone, then metallic channel can place with liquid copper alloy fusion Hub core iron, paints slime water, and back-up sand is pounded reality, and cross-arm is leaned on into sole center axle, scrapes hub sand mo(u)ld；Center line or hypsokinesis are checked after having scraped Wire tag and concentric reducer diameter, then paint clear water, then smear last layer loam, scrape a smooth, clean and tidy hub sand mo(u)ld again, Blown with carbon dioxide stand-by；

4th, striking pitch surface：Hub sand mo(u)ld height is adjusted, leaf model center line is directed at bisector, draws leaf profile, And runner gate and ingate can be opened up；It is after installing outer set square, Triangle ID plate is in place along circular arc line, put down mounted pitch Scraper plate, the radiation baseline position of secondary scraper plate is gone out with lining bar school, and is fixed, and scraper plate is made outer set square heart point, then is adjusted interior Set square is allowed to contact with setting the secondary scraper plate of position, and now, pitch plate present position is the center line of paddle sand mold, in Triangle ID Center line markings is carved on plate, fixes Triangle ID plate；

5th, phyllodium is made：Section template is nailed on corresponding line, model is vertical with pitch surface, in model Heart line and the alignment of pitch surface center line, molding sand is added between section template, after filling up molding sand, accomplishes one by sectional dimension with scraper The phyllodium of fairing；

6th, top box is made：Cover plate is put on mo(u)ld bottom half, last layer tap sand is spread on mo(u)ld bottom half, is stitched in die joint and angle Locate layer overlay paper, fill out appropriate water-glass sand, reality of successively pounding, surrounding is struck off into smoothing after consolidation is good, insert stomata, blow dioxy Change carbon, 8-10 venthole is stamped in nowel Sha Dun sides, and insert some stomatas at 60-80mm on the cover board, take out hub Sand mo(u)ld, smoothing in hub is suitable, mo(u)ld top half is prized with club and unclamps case；

7th, case is built：Repaiied and scraped by section template vestige in mold cavity surface with scraper, 10mm is reamed at leaf margin angle seam, Leaf root part scrapes circular arc according to drawing size；

8th, bottom is repaiied：Remove phyllodium repairing type, tamp former core axle hole；

9th, loam core makes：In one layer of bottom plate upper berth water-glass sand, arbor is put, on teeth directional, back-up sand consolidation, scraped with scraper plate Go out semicircle core, smoothing is suitable, blows carbon dioxide, takes out half core and is placed in soft place, air drain is outputed in the plane, according to same Method get another half fuse, two planes are coated into sodium silicate binder, by two pasting of core, the arbor iron wire at two Fasten, hang-up is repaiied suitable, and is drawn from loam core upper end, is painted alcohol-base paint, put fire drying；

Tenth, the making of down gate, runner gate, sprue cup：Down gate and runner gate are made with wooden model or steel pipe full pattern, it is horizontal Cast gate planted agent plugs filter residue mesh sheet, and sprue cup is made by process, the appropriate enlarging below each part joint, then will accomplished fluently Annex paint, enter baking oven and do；

11, mould assembling：The sand mold being baked is pulled out into stove, blown the sand-lime of mo(u)ld top half and mo(u)ld bottom half off before mould assembling, is aligned during mould assembling Mould assembling line, then enters kiln drying again；

12, running gate system is installed：The patency of cast passage, the position of sand grid, cast gate are checked when filling running gate system Cup diameter of outflow tube meets sprue diameter, and core and runner gate ensure to align.

By using above-mentioned technical proposal, mandrel is first inserted after under casing is chosen before moulding, by entering in 360 ° of orientation The correction that 90 ° of row, ensure the perpendicularity of mandrel；Striking under casing, insert sand mold and pound after reality, blown plane firmly by carbon dioxide, The hardness of plane is kept, facilitates subsequent operation, then the quantity according to blade on circular arc line marks bisector, passes through line Mode ensures that the quality of every can be equal；Sand mo(u)ld hub is made, the fusing point metallic channel lower than copper alloy, metal are bonded in hub loam core Groove plays a part of drainage in cast, makes in casting process, liquid copper alloy can be in the presence of the drainage of metallic channel Uniformly flow into, effectively strengthen the distribution of weight uniformity of casting, in order that metallic channel does not influence the quality of casting, metallic channel is rising It can be fused to after to the effect of drainage in liquid copper alloy, then place hub core iron, back-up sand is pounded reality, and cross-arm is leaned on into sole center Axle, sand mo(u)ld is scraped, center line or hypsokinesis wire tag and concentric reducer diameter are checked after having scraped, in order to strengthen casting medium casting weight Uniformity；Striking pitch surface, wherein, leaf model center line is directed at bisector, the radiation baseline of secondary scraper plate is gone out with lining bar school Position, and be fixed, corrected by these, can further strengthen the uniformity of the weight of casting；Make phyllodium, template surface Center line and pitch surface center line alignment, the center of gravity of hub cap fin is concentrated on centre, prevent centre-of gravity shift；Top box is made, is led to Cross when water-glass sand is added using successively pound it is real by the way of, make top box consolidation；Case is built, in leaf root part according to drawing Size scrapes circular arc, ensures circular arc the same, so that the distribution of weight of casting is uniform；Loam core makes, will in manufacturing process Core smoothing is suitable, can improve the smoothness of cast(ing) surface；The making of down gate, runner gate, sprue cup, filter is plugged in runner gate Slag mesh sheet can improve the quality of casting, avoid impurity from infiltrating in casting, and sprue cup makes according to process, can be very good The flow velocity and flow of the liquid metal in casting process are controlled, improves casting quality；Mould assembling, mould assembling line is directed at during mould assembling, can be with The Mass Distribution for strengthening casting is uniform；Running gate system is installed, checks the patency of cast passage, avoids blocking during cast, Whether the position of sand grid meets the requirements, and sprue cup diameter of outflow tube should comply with sprue diameter, checks core and runner gate Whether align, after supporting, half an hour, preceding mould temperature was poured in holding with blowtorch in baking temporary mould and sprue cup before cast.

The present invention is further arranged to：The accuracy of all pitch surfaces is checked, checks hub center line or hypsokinesis line and blade face spoke Coincideing property of ray, correct die joint, angle seam and runner gate.

By using above-mentioned technical proposal, it is necessary to check that hub center line or hypsokinesis line are emphatically when pitch surface is checked No and blade face radiation coincide, and such inspection can strengthen the distribution of weight uniformity of casting.

The present invention is further arranged to：According to technique pitch surface coordinate dimension, each point coordinates is measured with screw pitch gauge, and use 2- 3 cun of nail positioning, fix pitch surface.

By using above-mentioned technical proposal, each point coordinates is measured by screw pitch gauge, and positioned with nail, casting can be strengthened Size standard so that the quality of casting can be evenly distributed.

The present invention is further arranged to：The blade tip shape that phyllodium is made in the step 5 makes of blade tip core box, will Sand mold is put into core box consolidation, makes blade tip shape, and several fritters are divided at leaf center during taking-up, is put on pitch surface, adds sand to repair It is whole.

By using above-mentioned technical proposal, it can be adopted alternatively when phyllodium is made, pass through blade tip loam core Box makes phyllodium, can equally be made phyllodium.

The present invention is further arranged to：The sand mold being baked is put on smooth place, and floating dust is cleaned up, and is checked Whether sand mold is ftractureed, and floating sand is scraped off at cracking, is formed triangular groove, is repaired with coating plaster, need to repair again at serious cracking, Wire nail is inserted to reinforce.

By using above-mentioned technical proposal, check whether the sand mold being baked ftractures, and repair in time, casting can be improved Quality.

The present invention is further arranged to：The floating sand in type is blown off when repairing angle seam, cotton yarn is blocked in every blade profile chamber lagging edge, is prevented Sand grains rolls into blade type intracavitary when only repairing, and fills in angle with water-glass sand and stitches, and angle seam fills dry sand in midfield, in sand mold head Portion opens up venthole, while keeps mould temperature.

By using above-mentioned technical proposal, when repairing angle stitches, by the way that water-glass sand is tucked into angle seam, and Angle seam fills dry sand in midfield, can preferably avoid angle from stitching the influence to casting.

The present invention is further arranged to：The material of the metallic channel uses zinc, aluminium or tin material.

By using above-mentioned technical proposal, due to the water conservancy diversion that metallic channel plays a part of, while casting can not be influenceed again Quality, so the material that metallic channel uses is the material such as zinc, aluminium, tin, these material melting points are all lower than copper alloy, when liquid copper closes Gold runs into metallic channel and metallic channel can melted and then is dissolved into liquid copper alloy, will not also turn into the impurity of casting, simultaneously Drainage can also be played a part of.

In summary, the invention has the advantages that：

First, by continuous correction and measurement and positioning in manufacturing process, the quality of casting and the mark of size are improved Parasexuality；

Second, by the effect of drainage trough, in casting process, guiding of the liquid copper alloy according to drainage trough can be made, entered Row casting, enhance the distribution of weight uniformity of casting.

Embodiment

With reference to embodiment, the present invention will be described in detail.

Embodiment one：The processing technology step of hub cap fin is as follows：

First, the preparation before moulding：Worker is in place after under casing is chosen, and inserts mandrel, is corrected in 360 ° of orientation every 90 ° It is horizontal；

2nd, striking under casing：After under casing is in place, mandrel is in the center of under casing, insert sand mold and pound reality, use titanium dioxide Carbon blows plane firmly, marks bisector according to blade quantity on circular arc line, embedded disconnected saw blade marking, is covered with brick, in order to avoid Displacement is broken, ensures that the weight of every casting can be equal by way of line；

3rd, sand mo(u)ld hub is made：Based on the axle center of right overhead, with reference to the size dimension of hub, measured with model, must not be inclined It is small, the fusing point metallic channel that is used to drain lower than copper alloy, metallic channel energy and liquid copper alloy fusion are bonded on hub core iron, Then hub core iron is placed, paints slime water, back-up sand is pounded reality, and cross-arm is leaned on into sole center axle, scrapes sand mo(u)ld；Center is checked after having scraped Line or hypsokinesis wire tag and concentric reducer diameter, then paint clear water, then smear last layer loam, scrape again one it is smooth, clean and tidy Hub sand mo(u)ld, with carbon dioxide blow it is stand-by, dig out arbor in the big end intermediate symmetry of sand mo(u)ld, penetrate iron wire to lift by crane, metal Groove plays a part of drainage when cast, and in casting process, liquid copper alloy can be in the presence of the drainage of metallic channel Uniformly flow into, effectively strengthen the distribution of weight uniformity of casting, while in order that metallic channel does not influence the quality of casting, metallic channel It can be fused to after playing a part of drainage in liquid copper alloy；

4th, striking pitch surface：Hub sand mo(u)ld height is adjusted, leaf model center line is directed at bisector, draws leaf profile, Suitable back-up sand amount is considered again, and can open up runner gate and ingate；After installing outer set square, by Triangle ID plate along circular arc line In place, mounted pitch scraper plate is put down, the radiation baseline position of secondary scraper plate is gone out with lining bar school, and is fixed, scraper plate is made Outer set square heart point, then adjust Triangle ID plate and be allowed to contact with setting the secondary scraper plate of position, now, pitch plate present position is extremely The center line of paddle sand mold, center line markings is carved on interior set square, fix Triangle ID plate, then check that all pitch surfaces are It is no accurate, while check whether hub center line or hypsokinesis line coincide with blade face radiation, amendment die joint, angle seam and runner gate, Pitch surface is corrected, according to technique pitch surface coordinate dimension, each point coordinates is measured with screw pitch gauge, and is positioned with 2-3 cuns of nails, is fixed Pitch surface, by these corrections and measuring point and positioning, strengthen the uniformity of the weight of casting；

5th, phyllodium is made：Section template is nailed on corresponding line, model is vertical with pitch surface, to reduce thickness Spend deviation, model center line and pitch surface center line alignment, in order to avoid influence cross-sectional length, such as section is wider, it is longer be not easy and When pitch surface is vertical, the thickness error caused by the out of plumb of section should be estimated in advance, molding sand, consolidation are added between section template When preferably model both sides simultaneously consolidation, such model deflection is small, after filling up molding sand, accomplishes one by sectional dimension with scraper The phyllodium of fairing, to make to be easy to repairing type after unpacking, sprinkled on phyllodium " red soil sand ", phyllodium of the magic light into a fairing；

6th, top box is made：Cover plate is put on mo(u)ld bottom half, checks the height situation of gear shaping, according to face round steel on the basis of die bed Available cover plate is welded, last layer tap sand is spread on mo(u)ld bottom half, in die joint and angle seam etc. layer overlay paper, is easy to out Case, appropriate water-glass sand is filled out, reality of successively pounding, accomplish that consolidation is uniform as far as possible, it is real good particularly to be pounded at angle seam, and consolidation is good Surrounding is struck off into smoothing afterwards, stomata is inserted, blows carbon dioxide, 8-10 venthole is stamped in nowel Sha Dun sides, and on the cover board Some stomatas are inserted at 60-80mm, take out hub sand mo(u)ld, smoothing in hub is suitable, and hub die cavity size area of bed is checked, with long iron Rod can unpack mo(u)ld top half sled pine；

7th, case is built：Repaiied and scraped by section template vestige in mold cavity surface with scraper, until existing without vestige, such as needed Thickening then can be then suitable by groove depth smoothing first in surface Kai Ji roads shallow slot, such as considers that section template lays crooked and amendment sand mold Problem occurs during detection, can also suitably be repaired during repairing top box, 10mm or so, blade root are reamed at leaf margin angle seam Divide and circular arc is scraped according to drawing size；Mold cavity surface wants fairing close, and leaf margin is excessively uniform, fairing, should be reamed at angle seam 10mm or so, it is allowed to produce crack, but excessive can not be done in order to avoid being dried after mould assembling；If any raised on die joint, struck off, protected Fairing is held, should not be modified in order to avoid influenceing vane thickness；

8th, bottom is repaiied：Remove phyllodium repairing type after fixing fillet, tamp former core axle hole, prevent liquid copper alloy from revealing；

9th, loam core makes：In one layer of bottom plate upper berth water-glass sand, arbor is put, on teeth directional, back-up sand consolidation, scraped with scraper plate Go out semicircle core, smoothing is suitable, blows carbon dioxide, takes out half core and is placed in soft place, air drain is outputed in the plane, according to same Method get another half fuse, two planes are coated into sodium silicate binder, by two pasting of core, the arbor iron wire at two Fasten, hang-up is repaiied suitable, keeps core unimpeded, and is drawn from loam core upper end, is painted alcohol-base paint, is put fire drying, check each portion's chi It is very little, then a coating is uniformly coated with, entering to dry baking oven is done, and multiple smoothing is suitable, can heighten the smoothness of cast(ing) surface；

Tenth, the making of down gate, runner gate, sprue cup：Down gate and runner gate are made with wooden model or steel pipe full pattern, it is horizontal Cast gate planted agent plugs filter residue mesh sheet, and sprue cup will keep certain depth, and running gate system should be noted that opening, and by regulation process Make, pay attention to the appropriate enlarging below each part joint, it is accurate to dock, the annex paint that then will be accomplished fluently, enter stove Drying, by controlling the size of sprue cup to grasp the flow velocity and flow of the liquid metal in casting process, improve casting matter Amount；

11, mould assembling：The sand mold being baked is pulled out into stove, is put on smooth good place, floating ash is cleaned up, checks sand Whether type is ftractureed, and floating sand should be scraped off at cracking, forms triangular groove, is repaired with water-glass sand or coating plaster, will at serious cracking Again repair, insertion wire nail is reinforced, and blows the sand-lime of mo(u)ld top half and mo(u)ld bottom half off before mould assembling, mould assembling line is directed at during mould assembling, then again Enter kiln drying, whether drying is deformed after coming out of the stove with torch observation sand mold, crackle and damage, should be unpacked again finishing if any damage； When repairing angle seam, the floating sand in type is blown off, cotton yarn is blocked in every blade profile chamber lagging edge, prevent that sand grains rolls into blade die cavity during repairing It is interior, fill in angle with water-glass sand and stitch, angle seam can fill dry sand in midfield, be easy to sand mold to be vented, several go out is stamped on head Hole, while keep mould temperature；It is noted that being leveled up with stopper during loading board, reexamined after bolt fastening in type whether drop or cracking；

12, running gate system is installed：The patency of each cast passage is checked when filling running gate system, whether sand grid conforms to Ask, sprue cup diameter of outflow tube meets sprue diameter, checks whether core and runner gate align, central axis hole core clamp Measurement and positioning, the round steel thickness of solid welding core position are appropriate, it is impossible to and it is excessively thick, it is heated in order to avoid core presses to obtain tension, during cast swollen Core is set to ftracture after swollen, core may be cannot kept under control by crossing detailed rules and regulations, cause core to float, should be small half before cast after supporting When with blowtorch toast temporary mould and sprue cup again, mould temperature before holding is poured.

Embodiment two：It is with the difference of embodiment one：The making of phyllodium can be done using blade tip core box, first will Sand mold is put into core box consolidation, makes blade tip shape, divides several fritters from leaf centerline during taking-up, is put on pitch surface, unified Sand is added to repair, it is also possible to which wooden model blade tip is directly followed closely on pitch surface.

Described above is only the preferred embodiment of the present invention, and protection scope of the present invention is not limited merely to above-mentioned implementation Example, all technical schemes belonged under thinking of the present invention belong to protection scope of the present invention.It should be pointed out that for the art Those of ordinary skill for, some improvements and modifications without departing from the principles of the present invention, these improvements and modifications It should be regarded as protection scope of the present invention.

Claims (2)

1. A kind of 1. hub cap fin processing technology, it is characterised in that：Comprise the following steps：

   First, the preparation before moulding：Choose in place after under casing, insert mandrel, level is corrected to every 90 ° in 360 ° of orientation；

   2nd, striking under casing：Mandrel is in the center of under casing, insert molding sand and pound reality, with carbon dioxide by plane blow firmly, Bisector, marking are marked according to blade quantity on circular arc line；

   3rd, hub sand mo(u)ld is made：Based on the axle center of mandrel, with reference to the size dimension of hub, measured with model, on hub core iron The fusing point metallic channel that is used to drain lower than copper alloy is bonded, then metallic channel can place hub mud with liquid copper alloy fusion Arbor, paints slime water, and back-up sand is pounded reality, and cross-arm is leaned on into sole center axle, scrapes hub sand mo(u)ld；Center line or hypsokinesis line mark are checked after having scraped Note and concentric reducer diameter, then paint clear water, then smear last layer loam, a smooth, clean and tidy hub sand mo(u)ld are scraped again, with two Carbonoxide is blown stand-by；

   4th, striking pitch surface：Hub sand mo(u)ld height is adjusted, leaf model center line is directed at bisector, draws leaf profile, and energy Open up runner gate and ingate；It is after installing outer set square, Triangle ID plate is in place along circular arc line, put down mounted pitch and scrape Plate, the radiation baseline position of secondary scraper plate is gone out with lining bar school, and is fixed, and scraper plate is made outer set square heart point, then adjust interior three Gusset is allowed to contact with setting the secondary scraper plate of position, and now, pitch plate present position is the center line of paddle sand mold, in interior set square On carve center line markings, fix Triangle ID plate；

   5th, phyllodium is made：Section template is nailed on corresponding line, model is vertical with pitch surface, the center line of model It is aligned with pitch surface center line, molding sand is added between section template, after filling up molding sand, accomplishes a fairing by sectional dimension with scraper Phyllodium；

   6th, top box is made：Cover plate is put on mo(u)ld bottom half, last layer tap sand is spread on mo(u)ld bottom half, is spread at die joint and angle seam Last layer paper, appropriate water-glass sand is filled out, reality of successively pounding, surrounding is struck off into smoothing after consolidation is good, inserted stomata, blow titanium dioxide Carbon, 8-10 venthole is stamped in nowel Sha Dun sides, and insert some stomatas at 60-80mm on the cover board, take out hub sand Mould, smoothing in hub is suitable, mo(u)ld top half is prized with club and unclamps case；

   7th, case is built：Repaiied and scraped by section template vestige in mold cavity surface with scraper, 10mm, blade root are reamed at leaf margin angle seam Part scrapes circular arc according to drawing size；

   8th, bottom is repaiied：Remove phyllodium repairing type, tamp former arbor hole；

   9th, loam core makes：In one layer of bottom plate upper berth water-glass sand, arbor is put, on teeth directional, back-up sand consolidation, half is scraped with scraper plate Circle core, smoothing is suitable, blows carbon dioxide, takes out half core and is placed in soft place, air drain is outputed in the plane, according to same side Method gets another half fuse, and two planes are coated into sodium silicate binder, and by two pasting of core, the arbor at two is pricked with iron wire Jail, hang-up are repaiied suitable, and are drawn from loam core upper end, are painted alcohol-base paint, put fire drying；

   Tenth, the making of down gate, runner gate, sprue cup：Down gate and runner gate, runner gate are made with wooden model or steel pipe full pattern Planted agent plugs filter residue mesh sheet, and sprue cup is made by process, and the appropriate enlarging below each part joint is then attached by what is accomplished fluently Part paint, enter baking oven and do；

   11, mould assembling：The sand mold being baked is pulled out into stove, blown the sand-lime of mo(u)ld top half and mo(u)ld bottom half off before mould assembling, is directed at mould assembling during mould assembling Line, then enter kiln drying again；

   12, running gate system is installed：The patency of cast passage, the position of sand grid are checked when filling running gate system, sprue cup goes out Water pipe diameter meets sprue diameter, and core and runner gate ensure to align；

   The accuracy of all pitch surfaces is checked, checks hub center line or hypsokinesis line and the identical property of blade face radiation, amendment die joint, folder Angle seam and runner gate；

   According to technique pitch surface coordinate dimension, each point coordinates is measured with screw pitch gauge, and is positioned with 2-3 cuns of nails, fixes pitch surface；

   The blade tip shape that phyllodium is made in the step 5 is made of blade tip core box, and sand mold is put into core box consolidation, makes leaf Tip shape, several fritters are divided during taking-up at leaf center, is put on pitch surface, adds sand to repair；

   The sand mold being baked is put on smooth place, and floating dust is cleaned up, and checks whether sand mold ftractures, and is scraped at cracking Floating sand is removed, triangular groove is formed, is repaired with coating plaster, need to repair again at serious cracking, insertion wire nail is reinforced；

   The floating sand in type is blown off when repairing angle seam, cotton yarn is blocked in every blade profile chamber lagging edge, prevents that sand grains rolls into blade type during repairing Intracavitary, fill in angle with water-glass sand and stitch, angle seam fills dry sand in midfield, opens up venthole on sand mold head, keeps simultaneously Mould temperature.
2. 2. hub cap fin processing technology according to claim 1, it is characterised in that：The material of the metallic channel is using zinc, aluminium Or tin material.