铸造工艺流程图

Painting WarehouseDongtai Marine Fittings Co., LtdFile No.：DTCP/GY-01-AProduction Process File Page2 Total page: 2Edited by Approved by Version No. Revision times Effective date2009.1.1A 0Dongtai Marine Fittings Co., LtdFile No.：DTCP/GY-02-AWooden Former Process File Page1 Total page: 1 Edited by Approved by Version No. Revision times Effective dateA 02009.1.11Wooden former Processing DrawingWooden former workers shall be familiar with the processing drawing first.Consider the wooden former structure according to processing drawing.2Lofting2.1 Increase and release the contraction allowance in accordance with the measurementsof the drawing.2.2 Release processing allowance according to processing drawing.2.3 Make mode direction according to sub-surface mode. The slope of surface whichneeds to be processed shall be done according to increase, while surface which needs notto be processed shall be done by positivity and negativity.2.4 Those which need to take a variety of processing corrections and riser subsidies shallbe marked in lofting.2.5 Draw the shape and size of the core head and mark the gap between core heads.2.6 If any error of the drawing is found in lofting, report to the techical department timelyand the errors shall be corrected by them.3 Wooden former production3.1 Wooden former structure should be solid and firm and wood should be dry.3.2 Tape nails shall be applied to all the junctions of castings for connection.3.3 All the junctions of castings shall be made into R shape.3.4 Install mold iron and the specimen.4 Painting4.1 After the wooden former is completed, it shall be sand polished by sand feather.4.2 Paint two covers of putty paint.5 After the completion of wood mould, it should be inspected for approval before put into production.Attached files: 1. Wooden Former Technology Card2. Drawing of Wooden Former StructureDongtai Marine Fittings Co., LtdFile No.：DTCP/GY-03-ASand Mixing Operation Procedures Page 1 Total page: 1Edited by Approved by Version No. Revision times Effective dateA 02009.1.1 1. Sand mixer is important equipment for water glass sand production and accordinglyspecial operators must be assigned for its operation and maintenance. The operators musthave a detailed understanding of the basic knowledge of the machine working principle, operation and maintenance.2. Before work, first of all turn on the general power switch in electric control cabinet,check whether “operation, check" knob hits “operation” location and whether the “power” indicator on electric control cabinet and operation box is illuminated.3. After the mould and sandbox are ready, press the “start sand mixing” button, the sandmixing system will automatically operate according to preset program. The “first sand”mixed at the beginning of mixing can be released or used as back sand.4. When the sandbox is filled with sand, press the “stop mixing” button in advance. Stopadding curing agent, water glass and sand and mixer cage continues to rotate for another10 seconds, and then the mixer will be drained of its remaining sand.5. When there is a need to stop in the middle of sand mixing, press the “pause sand mixing” button and stop adding curing agent, water glass and sand. Mixer stops too, butthe pause time shall not exceed the usable time of molding sand. It is forbidden to leavethe remaining sand in the sand mixer for long. If operation stops or no molding sand isused for a long time, press the “sand check and empty” button and drain all the remainingsand within.6. The treatment of first and last sand can be conducted according to the situation.7. During sand mixing, the liquid level within the water glass and curing agent containersand material level of sand storage silo shall be checked frequently to ensure the rightadding of sand, curing agent and water glass.8. According to the requirements of sand filling during sand mixing, Grade 1 and Grade 2shall be steered to status of braking to ensure the proper operation of the machine.Molding sand matching：File No.：DTCP/GY-03-A Dongtai Marine Fittings Co., Ltd Sand Mixing Operation Procedures Page 1 Total page: 1Edited by Approved byVersion No.Revision timesEffective dateA 0 2009.1.1Molding sand matching(t he proportionof new sand to old) Waterglass additio n Curing agent additio nTensio n strengt hwithin 24 hours (MPa)Usable time （min ）Mould drawin g time （min ）Mould core storage quality(da ys for storage)Castin g qualit y Remar ksFacin g sand core sand 1：4 2.5-3%15-20%＞0.620～3060～90 6 ≤5tFacin g sand 1：4 2.5-3%15-20%＞0.830～4060～906≤5tBack sand0：1 1.8-2.5%15-20%＞0.430～4060～906Note: The model and added quantity of water glass and curing agent shall be determined according to the experimental results in the lab.File No.：DTCP/GY-04-ADongtai Marine Fittings Co., LtdMolding and Core-making Process File Page 1 Total page: 1Edited by Approved by Version No. Revision times Effective dateA 02009.1.1 1Preparation before operation1.1 Get familiar with process file, understand processing characteristics and make sure ofkey operation steps.1.2 Check the certificates of model and core box.1.3 Check whether the movable blocks and affiliates of model and core box are complete,good and fit.1.4 Check the status of sandbox and core iron.1.5 Check the preparation of all materials, such as release agent, ventilation materials,coating materials, fire bricks for gate bottom, fireproof material and pouring system.2 Operation tips2.1 Wipe up the model, core box and brush the release agent.2.2 Place properly the runner, riser, and chill and boxed cofferdam. And when cofferdam is boxed, do not touch model and the preset runner, riser and chill.2.3 Fill in with facing sand the gate, riser, chill, corner and moving blocks where the position can be easily changed but not easy to filled firm. Make them firmly filled withhand or wood sticks while filling a large amount of sand till surrounding and covering thewhole model.2.4 For core-making, pay attention to the core iron position and height. The ventilation materials should be in appropriate number and make the mold against the inside wall ofcore box evenly distributed.2.5 When using fire ceramic tubes and elbow joint to cast pouring system, pay attention tothe seals of joints and blocks of openings in case molding sand should fall into them whilefilling sand.2.6 When using non-stop sand mixer to supply sand, the “first sand” can not be used asfacing sand.File No.：DTCP/GY-04-ADongtai Marine Fittings Co., LtdMolding and Core-making Process File Page 1 Total page: 1Edited by Approved by Version No. Revision times Effective date2009.1.1A 02.7 The pattern drawing time of water glass from self-hardening sand needs to be controlled. The specific time needs to be considered based on such factors as proportion ofcuring agent, sand temperature, and environment temperature and model materials andsubject to trial through operation practice. A balance of model needs to be kept duringmanual pattern drawing. Wood hammer or rubber mallet can be employed to knock fourangles for pattern drawing.2.8 The core box can be dismantled earlier, just strong enough for sand core not to fallapart. Pay attention to the sequence and direction of those parts when they are torn open.They shall be dismantled one bye one and cleaned, assembled sequentially and placed properly. After the core box is dismantled, all moving blocks and moving parts are reassembled and further fastened for saving or follow-up operation.2.9 After pattern drawing and the core is taken out, check the status of cavity and core andgo through necessary modifications, such as flattening the seam sand between movingparts and digging out lifting bar.2.10 Paint according to the regulation and avoid flows and accumulations. If alcohol-basedcoating is used, light it timely to dry it; for some specific parts, spray burner can be employed for further drying but avoid over-burn. The surface temperature of mould andcore must not exceed 180 degree.Attached files 3: Modeling Technology CardFile No.：DTCP/GY-05-ADongtai Marine Fittings Co., LtdAlkalescent Electric Arc FurnacePage1 Total page: 4Steel-Making Process FileEdited by Approved by Version No. Revision times Effective date2009.1.1A 0Electric Arc Furnace Steel-Making ProcessElectric arc furnace steel-making process can be divided into five stages: collection ofraw materials, preparation before smelting, melting period, oxidation period and reduction period.1Collection of raw materialsScrap is the main material for electric arc furnace steel-making and accordingly thequality of scrap is closely related to the quality of steel, costs and electric furnace productivity. Therefore, the following requirements for scrap should be met:1.1 The surface of scrap shall be clean, without serious rusty erosion and oil stains.1.2 There shall be no such nonferrous metals as lead, tin, arsenic, zinc, and copper in scrap.1.3 There shall be no sealed container, inflammable, explosive and poisonous substancesin scrap to secure the safe production.1.4 It shall be clarified that the scrap shall be not rich in phosphor and sulphur as chemical composition.1.5 The shape and size of scrap can not be too large (its section area shall not exceed150mm×150mm, the maximum length shall be no more than 350mm).During electric arcfurnace steel-making, pig iron is normally used to increase carbon addition, which usuallydoes not exceed 30% of furnace charge.1.6. The scrap shall be classified, marked and stored according to their chemical composition.Dongtai Marine Fittings Co., LtdFile No.：DTCP/GY-05-AAlkalescent Electric Arc FurnacePage1 Total page: 4Steel-Making Process FileEdited by Approved by Version No. Revision times Effective date2009.1.1A 02 Preparation before smeltingBurdening is one indispensable part of electric arc furnace steel-making process, and whether it is reasonable concerns whether steel-making can normally go through smelting operation. Reasonable burdening can reduce smelting time. It shall be paid attention in burdening that: firstly, correctly calculate the burden and precisely weigh furnace charge; secondly, size of furnace charge shall be matched according to proportion for good charging and fast smelting; thirdly, all kinds of furnace charge shall be matched and usedbased on quality requirements of steel and smelting method; fourthly, burdening constituents must fulfill processing requirements. Generally, smelting method has the following requirements for the main elements content in furnace charge:2.1 Carbon content. The carbon content in the furnace charge shall guarantee that during oxidation period there is sufficient carbon to conduct carbonization reaction in the hope of removing gas and sundries. The carbon addition shall be determined based upon three factors: carbon burn during melting period, decarbonization volume in oxidation periodand carburization volume in reduction period. It is required that when furnace charge ismelted fully, carbon content level in steel shall be 0.3-0.4% higher than the lower limit of finished product standard.2.2 Silicon content. Normally, the silicon content is no more than 0.8% of furnace charge.2.3 Manganese content. The manganese content will not be taken into consideration forthe matching of regular steel type and its content usually shall be less than 0.3% after it ismelted fully.Phosphor and sulphur content shall basically be very low. The lower, the better. Phosphor content usually shall be less than 0.05% after it is melted fully.In order to make furnace charge inside dense, large materials, middle materials andsmall materials must be matched properly, of which small materials take 15%～20%,middle materials 40%～50%，and large materials 40%。