CN105506468A - Preparation method of buffer - Google Patents
Preparation method of buffer Download PDFInfo
- Publication number
- CN105506468A CN105506468A CN201510969455.9A CN201510969455A CN105506468A CN 105506468 A CN105506468 A CN 105506468A CN 201510969455 A CN201510969455 A CN 201510969455A CN 105506468 A CN105506468 A CN 105506468A
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- CN
- China
- Prior art keywords
- sand
- arenaceous shell
- snubber
- preparation
- buddhist nun
- Prior art date
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Classifications
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/04—Ferrous alloys, e.g. steel alloys containing manganese
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22C—FOUNDRY MOULDING
- B22C1/00—Compositions of refractory mould or core materials; Grain structures thereof; Chemical or physical features in the formation or manufacture of moulds
- B22C1/16—Compositions of refractory mould or core materials; Grain structures thereof; Chemical or physical features in the formation or manufacture of moulds characterised by the use of binding agents; Mixtures of binding agents
- B22C1/20—Compositions of refractory mould or core materials; Grain structures thereof; Chemical or physical features in the formation or manufacture of moulds characterised by the use of binding agents; Mixtures of binding agents of organic agents
- B22C1/22—Compositions of refractory mould or core materials; Grain structures thereof; Chemical or physical features in the formation or manufacture of moulds characterised by the use of binding agents; Mixtures of binding agents of organic agents of resins or rosins
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22C—FOUNDRY MOULDING
- B22C9/00—Moulds or cores; Moulding processes
- B22C9/22—Moulds for peculiarly-shaped castings
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/02—Ferrous alloys, e.g. steel alloys containing silicon
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/08—Ferrous alloys, e.g. steel alloys containing nickel
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/12—Ferrous alloys, e.g. steel alloys containing tungsten, tantalum, molybdenum, vanadium, or niobium
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16F—SPRINGS; SHOCK-ABSORBERS; MEANS FOR DAMPING VIBRATION
- F16F7/00—Vibration-dampers; Shock-absorbers
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- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- General Engineering & Computer Science (AREA)
- Mold Materials And Core Materials (AREA)
Abstract
A preparation method of a buffer comprises the following preparation steps: at first, mixing No. 2 Bangni thermosetting resin with quartz sand to obtain sand for preparing a sand shell of the buffer, wherein the using amount of the thermosetting resin is 1.3%-2.0% of the weight of the quartz sand; then placing the sand in a sand shooting machine to obtain the sand shell with a buffer cavity; next pouring molten metal obtained through smelting raw materials of the buffer in the sand shell; and within 0.6-1.5 h after the pouring is finished, conducting pyrolysis devolatilization on the No. 2 Bangni thermosetting resin in the sand shell, and scattering the quartz sand from the condensed metal surface to obtain the buffer. The preparation method has the advantages that the sand is scattered completely, manual sanding is not required, and the production cost is low.
Description
Technical field
The present invention relates to a kind of snubber casting technology field, is specifically related to a kind of preparation method of snubber.
Background technology
Snubber is parts very crucial in motor vehicle, the quality of its quality directly affects the anti-seismic performance of vehicle and the safety performance of vehicle, the super-huge snubber particularly train used, the quality of its quality is more crucial, the snubber that train uses, as shown in Figure 1: be generally a rectangular-shaped buffer main body, main body arranged multiple open holes, groove etc.; Its inside also arranges the structures such as hole, installation position and screens.The snubber of this structure is due to the singularity of structure, traditional forging method cannot realize, what current use was more is castmethod, namely concrete technology flow process is as follows: 1) production process preparation, according to the parts drawing that will produce, production lot and time of delivery, formulate production technique scheme and technical papers, draw foundary methods drawing; 2) Operational preparation, comprises toolings such as preparing fusing material, molding and core making material and apperance, core box, sandbox; 3) moulding and coremaking; 4) fusing and cast; 5) master operation such as peeling and castings examination.Forming Theory: METAL HEATING PROCESS is melted, make it have mobility, then be poured in the effigurate casting mold die cavity of tool, under the effect of gravity or external force (pressure, centrifugal force, electromagnetic force etc.), be full of die cavity, cool and be frozen into a kind of metal forming method of foundry goods (or part).Above-mentioned castingprocesses needs to adopt a large amount of sand, and sand mold manufacturing process is many, and follow-up sand removal task weight, workman needs the sanding of large workload, thus considerably increases the labor capacity of workman, and molding floor's dust is large, production cost is high.
Summary of the invention
The present invention is directed to the above-mentioned deficiency of prior art, provide a kind of sand defeated and dispersed clean, without the need to the preparation method of artificial sanding, snubber that production cost is low.
In order to solve the problems of the technologies described above, the technical solution used in the present invention is: a kind of preparation method of snubber, and preparation process comprises:
(1) first mixed with quartz sand by nation Buddhist nun No. 2 thermosetting resins, obtain the sand material preparing snubber arenaceous shell, the usage quantity of nation Buddhist nun No. 2 thermosetting resins is the 1.3-2.0% of quartz sand weight;
(2) then sand material prepared by step (1) is put into and penetrate sand machine, sand material is heated to 140-160 DEG C, then sandblasting moulding under 4-6 atmospheric pressure, obtains the arenaceous shell with snubber die cavity, arenaceous shell naturally cooling is stand-by, and the thickness of arenaceous shell is 30-70mm;
(3) raw material of snubber is prepared according to each component configuration of following weight percent: carbon (C) 0.3-0.35%, manganese (Mn) 1.0-1.2%, silicon (Si) 0.2-0.4%, chromium (Cr) 0.30-0.50%, molybdenum (Mo) 0.10-0.15%, nickel (Ni)≤0.25%, sulphur (S)≤0.06%, phosphorus (P)≤0.05%, surplus is iron; Then raw material Hybrid Heating melts to 1000-1300 DEG C, in the arenaceous shell then prepared to step (2) by the pouring metal melt of melting;
(4) to be cast complete after 0.6-1.5h, No. 2 thermosetting resin pyrolysis devolatilizations of the nation Buddhist nun in arenaceous shell, quartz sand is scattered from the metallic surface of condensation, obtain buffer products.
As preferably, the usage quantity of nation Buddhist nun No. 2 thermosetting resins described in step (1) is the 1.5-1.6% of quartz sand weight; Adopt this proportioning, the casting mold effect of arenaceous shell can well be realized, also can ensure that arenaceous shell disperses in time simultaneously.
As preferably, the thickness of the arenaceous shell described in step (2) is 50-70m; Adopt this thickness, can ensure that metal liquid abundant condensation in arenaceous shell is shaping, also can ensure that arenaceous shell disperses in time simultaneously.
Nation Buddhist nun of the present invention No. 2 thermosetting resins (BN-02), buy the nation Buddhist nun solidifying agent sold from nation Buddhist nun chemical industry (Tianjin) company limited.
Advantage of the present invention and beneficial effect:
1. the present invention adopts compound nation Buddhist nun No. 2 thermosetting resins and quartz sand being carried out mixing first, be used for preparing the arenaceous shell with snubber die cavity, then in arenaceous shell, directly the metal liquid of snubber is prepared in cast, although molten metal condensation heat release, by No. 2 thermosetting resin thermal degradation volatilizations of the nation Buddhist nun in arenaceous shell, quartz sand then disperses to come off due to the cohesive action without nation Buddhist nun No. 2 thermosetting resins naturally, thus directly obtains ganoid buffer products; The present invention by the thickness of conservative control arenaceous shell and the addition of nation Buddhist nun No. 2 thermosetting resins, fully ensures metal liquid cooling being but scattered the time of molding effect and quartz sand; Thus abandoned numerous and diverse operation and workman's sanding operation of traditional sand mould casting method, greatly save manpower and reduce production cost.And this technique is different from other conventional casting techniques especially: adopt resin that is formaldehydeless, reactive phenol to achieve without sand removal operation; The advantage of sand reclamation rate about more than 95%.
2. preparation method of the present invention, does not need workman to manufacture sand mold, and preparation section is simple, and work situation is greatly improved, more environmental protection, pollutes little; And the sandblast machine adopted manufactures the process of arenaceous shell to be similar to injection moulding machine preparing product the same, by rational design temperature and blasting pressure, just can obtain qualified arenaceous shell product, arenaceous shell inside is the die cavity identical with bumper shapes; The present invention adopts pressure moulding equipment, compression molding, and casting accuracy can reach CT6 level (casting GB 6 grades), distinguishes other techniques and promotes 2 grades; Then direct by heating raw materials melt casting in the die cavity of arenaceous shell, molten metal condensation, the arenaceous shell in outside leaves, and namely obtains product, does not need the operations such as founding, shakeout, sanding; Save labour intensity and labor force: shaping, carrying all adopts automated operation, saves manpower 1/3, save 2/3 than " solvent casting " than other " resin sand casting " technique.
3. No. 2 thermosetting resins of the present invention are due to himself weave construction advantage, make the oil film that molding sand surface has one deck special, molding sand surface stability and good security, are beneficial to surface quality of continuous castings and improve; At high temperature there is pyrolysis and form bright carbon in top layer, casting mold and metal interface form reducing atmosphere, prevents the oxidation of metallic surface, makes surface roughness refinement, smooth; And resin decomposition thing formaldehyde, reactive phenol, environmental protection more, safety; And the quartz sand be scattered can fully recycle.The economy of present invention process: other " resin sand casting " technique profits comparable improve 15-20%, improves 25-30% than " solvent casting " profit.
Accompanying drawing explanation
Fig. 1 buffer structure schematic diagram of the present invention.
Embodiment
Below by embodiment, the present invention is described in further detail, but the present invention is not only confined to following examples.
Accompanying drawing 1 is snubber of the present invention.
Embodiment 1
(1) first mixed with quartz sand by nation Buddhist nun No. 2 thermosetting resins, obtain the sand material preparing snubber arenaceous shell, the usage quantity of nation Buddhist nun No. 2 thermosetting resins is 1.5% of quartz sand weight;
(2) then sand material prepared by step (1) is put into and penetrate sand machine, sand material is heated to 150-155 DEG C, then sandblasting moulding under 6 atmospheric pressure, obtains the arenaceous shell with snubber die cavity, arenaceous shell naturally cooling is stand-by, and the thickness of arenaceous shell is 50mm;
(3) raw material of snubber is prepared according to each component configuration of following weight percent: carbon (C) 0.31%, manganese (Mn) 1.0%, silicon (Si) 0.3%, chromium (Cr) 0.4%, molybdenum (Mo) 0.12%, nickel (Ni) 0.20%, sulphur (S) 0.05%, phosphorus (P) 0.04%, surplus is iron; Then raw material Hybrid Heating melts to 1000-1300 DEG C, in the arenaceous shell then prepared to step (2) by the pouring metal melt of melting;
(4) to be cast complete after, No. 2 thermosetting resin pyrolysis devolatilizations of the nation Buddhist nun after 1h in arenaceous shell, quartz sand is scattered from the metallic surface of condensation, obtain buffer products.
Embodiment 2
(1) first mixed with quartz sand by nation Buddhist nun No. 2 thermosetting resins, obtain the sand material preparing snubber arenaceous shell, the usage quantity of nation Buddhist nun No. 2 thermosetting resins is 1.8% of quartz sand weight;
(2) then sand material prepared by step (1) is put into and penetrate sand machine, sand material is heated to 155-160 DEG C, then sandblasting moulding under 5 atmospheric pressure, obtains the arenaceous shell with snubber die cavity, arenaceous shell naturally cooling is stand-by, and the thickness of arenaceous shell is 60mm;
(3) raw material of snubber is prepared according to each component configuration of following weight percent: carbon (C) 0.35%, manganese (Mn) 1.1%, silicon (Si) 0.36%, chromium (Cr) 0.46%, molybdenum (Mo) 0.14%, nickel (Ni) 0.10%, sulphur (S) 0.03%, phosphorus (P) 0.03%, surplus is iron; Then raw material Hybrid Heating melts to 1260-1300 DEG C, in the arenaceous shell then prepared to step (2) by the pouring metal melt of melting;
(4) to be cast complete after, 0.6h, No. 2 thermosetting resin pyrolysis devolatilizations of the nation Buddhist nun in arenaceous shell, quartz sand is scattered from the metallic surface of condensation, obtain buffer products.
Embodiment 3
(1) first mixed with quartz sand by nation Buddhist nun No. 2 thermosetting resins, obtain the sand material preparing snubber arenaceous shell, the usage quantity of nation Buddhist nun No. 2 thermosetting resins is 1.6% of quartz sand weight;
(2) then sand material prepared by step (1) is put into and penetrate sand machine, sand material is heated to 140-145 DEG C, then sandblasting moulding under 4.5 atmospheric pressure, obtains the arenaceous shell with snubber die cavity, arenaceous shell naturally cooling is stand-by, and the thickness of arenaceous shell is 35mm;
(3) raw material of snubber is prepared according to each component configuration of following weight percent: carbon (C) 0.31%, manganese (Mn) 1.0%, silicon (Si) 0.22%, chromium (Cr) 0.35%, molybdenum (Mo) 0.11%, nickel (Ni) 0.15%, sulphur (S) 0.03%, phosphorus (P) 0.03%, surplus is iron; Then raw material Hybrid Heating melts to 1000-1050 DEG C, in the arenaceous shell then prepared to step (2) by the pouring metal melt of melting;
(4) to be cast complete after, 1h, No. 2 thermosetting resin pyrolysis devolatilizations of the nation Buddhist nun in arenaceous shell, quartz sand is scattered from the metallic surface of condensation, obtain buffer products.
Carry out Performance Detection to sample prepared by embodiment, its detected result is as shown in little table 1:
Table 1
From above-mentioned detection data, it is high that method prepared by the present invention has unit elongation, and impelling strength is strong, and the advantage that hardness is high, meets the environment for use requirement of snubber completely.
Sand machine of penetrating of the present invention can adopt commercially available coated sand core shooting machine, principle of work: utilize pressurized air molding sand to be injected uniformly the pre-consolidation of sandbox, and then apply pressure and carry out compacting, conventional has vertical parting flaskless shoot-squeeze moulding machine and horizontal parting slip flask shoot-squeeze moulding machine, vertical parting flaskless shoot-squeeze moulding machine moulding is without sandbox, the moulding room with template directly injected by molding sand, institute's sand mold dimensional precision of making is high, there is die cavity on sandbox two sides, productivity is high, but lower core difficulty, molding sand quality is required strict, horizontal parting slip flask shoot-squeeze moulding machine utilizes sandbox to carry out moulding, rear mould assembly drawing made by sand mold, lower core is convenient, productivity is high.Above-mentionedly penetrate sand machine and principle of work is all applicable to the present invention.
Claims (3)
1. a preparation method for snubber, is characterized in that: preparation process comprises:
(1) first mixed with quartz sand by nation Buddhist nun No. 2 thermosetting resins, obtain the sand material preparing snubber arenaceous shell, the usage quantity of nation Buddhist nun No. 2 thermosetting resins is the 1.3-2.0% of quartz sand weight;
(2) then sand material prepared by step (1) is put into and penetrate sand machine, sand material is heated to 140-160 DEG C, then sandblasting moulding under 4-6 atmospheric pressure, obtains the arenaceous shell with snubber die cavity, arenaceous shell naturally cooling is stand-by, and the thickness of arenaceous shell is 30-70mm;
(3) raw material of snubber is prepared according to each component configuration of following weight percent: carbon 0.3-0.35%, manganese 1.0-1.2%, silicon 0.2-0.4%, chromium 0.30-0.50%, molybdenum 0.10-0.15%, nickel≤0.25%, sulphur≤0.06%, phosphorus≤0.05%, surplus is iron; Then raw material Hybrid Heating melts to 1000-1300 DEG C, in the arenaceous shell then prepared to step (2) by the pouring metal melt of melting;
(4) to be cast complete after 0.6-1.5h, No. 2 thermosetting resin pyrolysis devolatilizations of the nation Buddhist nun in arenaceous shell, quartz sand is scattered from the metallic surface of condensation, obtain buffer products.
2. the preparation method of snubber according to claim 1, is characterized in that: the usage quantity of nation Buddhist nun No. 2 thermosetting resins described in step (1) is the 1.5-1.6% of quartz sand weight.
3. the preparation method of snubber according to claim 1, is characterized in that: the thickness of the arenaceous shell described in step (2) is 50-70m.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510969455.9A CN105506468B (en) | 2015-12-21 | 2015-12-21 | The preparation method of buffer |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510969455.9A CN105506468B (en) | 2015-12-21 | 2015-12-21 | The preparation method of buffer |
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| CN105506468A true CN105506468A (en) | 2016-04-20 |
| CN105506468B CN105506468B (en) | 2017-07-25 |
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| CN201510969455.9A Active CN105506468B (en) | 2015-12-21 | 2015-12-21 | The preparation method of buffer |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110576175A (en) * | 2019-09-29 | 2019-12-17 | 张家港科杰机械装备有限公司 | Production process for chemical castings |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102094113A (en) * | 2009-12-09 | 2011-06-15 | 宁波金汇精密铸造有限公司 | Heat treatment process of train buffer material |
| CN102094152A (en) * | 2009-12-09 | 2011-06-15 | 宁波金汇精密铸造有限公司 | Train buffer material |
| CN102094112A (en) * | 2009-12-09 | 2011-06-15 | 宁波金汇精密铸造有限公司 | Heat treatment process of alloy steel product |
| CN102756095A (en) * | 2011-04-27 | 2012-10-31 | 陆宝庆 | Casting process of diesel engine |
| CN104001870A (en) * | 2014-04-02 | 2014-08-27 | 杭州萧山之江永磁材料有限公司 | Method for modeling aluminum-nickel-cobalt magnet steel through sand ejecting |
-
2015
- 2015-12-21 CN CN201510969455.9A patent/CN105506468B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102094113A (en) * | 2009-12-09 | 2011-06-15 | 宁波金汇精密铸造有限公司 | Heat treatment process of train buffer material |
| CN102094152A (en) * | 2009-12-09 | 2011-06-15 | 宁波金汇精密铸造有限公司 | Train buffer material |
| CN102094112A (en) * | 2009-12-09 | 2011-06-15 | 宁波金汇精密铸造有限公司 | Heat treatment process of alloy steel product |
| CN102756095A (en) * | 2011-04-27 | 2012-10-31 | 陆宝庆 | Casting process of diesel engine |
| CN104001870A (en) * | 2014-04-02 | 2014-08-27 | 杭州萧山之江永磁材料有限公司 | Method for modeling aluminum-nickel-cobalt magnet steel through sand ejecting |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110576175A (en) * | 2019-09-29 | 2019-12-17 | 张家港科杰机械装备有限公司 | Production process for chemical castings |
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| CN105506468B (en) | 2017-07-25 |
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