1、Designation: D2230 17Standard Test Method forRubber PropertyExtrudability of UnvulcanizedCompounds1This standard is issued under the fixed designation D2230; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision
2、. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This test method covers the determination of the extrud-ability of unvulcanized SBR and NBR rubber compoundsthrough a screw-type ex
3、truder equipped with ASTM ExtrusionDie, Garvey type. This test method is designed to allow theobservation of the appearance and contours of the extrusion.Rating systems are provided along with recipes for compoundsof known extrusion characteristics. The utility of the testmethod for evaluating rubbe
4、rs or compounding materials otherthan those listed has not been established. Since extrusionmachines differ among laboratories, the procedure includestechniques that minimize differences between machines.1.2 The values stated in SI units are to be regarded as thestandard. The values given in parenth
5、eses are for informationonly.1.3 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety, health, and environmental practices and deter-mine the applicability of regula
6、tory limitations prior to use.1.4 This international standard was developed in accor-dance with internationally recognized principles on standard-ization established in the Decision on Principles for theDevelopment of International Standards, Guides and Recom-mendations issued by the World Trade Org
7、anization TechnicalBarriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:2D3182 Practice for RubberMaterials, Equipment, and Pro-cedures for Mixing Standard Compounds and PreparingStandard Vulcanized SheetsD3185 Test Methods for RubberEvaluation of SBR(Styrene-Butadiene Rubber)
8、 Including Mixtures With OilD3187 Test Methods for RubberEvaluation of NBR(Acrylonitrile-Butadiene Rubber)2.2 ASTM Adjuncts:Appearance Ratings Photographs33. Summary of Test Method3.1 A standard compound is prepared and extruded througha specially shaped die that produces an extrusion having acombin
9、ation of relatively flat surfaces, sharp corners, and thinsections. The operating conditions are varied until a satisfac-tory extrusion of the standard compound is obtained. The testcompound is then extruded, using the conditions justestablished, and the nature of the extrusion is rated visually for
10、smoothness, sharp corners, and integrity of thin sections.4. Significance and Use4.1 One objective in the extrusion of rubber compounds isto obtain a smooth extrusion that closely reproduces thecontours of the extrusion die. This test method provides for asubjective determination of this under contr
11、olled conditions.As the rating is subjective, it does not lend itself readily toincorporation as a specification requirement. It does not mea-sure other aspects of extrudability such as rate of extrusion ordie swell in a quantitative manner.5. Apparatus5.1 Mill, 150 by 300 mm (6 by 12 in.), as descr
12、ibed inPractice D3182.5.2 DieASTM Extrusion Die, Garvey type, conforming tothe dimensions and shape shown in Fig. 1 shall be used.NOTE 1Good precision in the manufacture of the opening in the diecan be attained by ultrasonic machining. The die should be replaced whena dimension has changed by 0.02 m
13、m (0.001 in.) from its original valueor if the die is damaged.5.3 AdapterA hollow, cone-shaped ring insert taperedwith an angle of 30 6 15 (shown in Fig. 2) shall be used with1This test method is under the jurisdiction of ASTM Committee D11 on Rubberand Rubber-like Materials and is the direct respon
14、sibility of Subcommittee D11.12on Processability Tests.Current edition approved Oct. 1, 2017. Published November 2017. Originallyapproved in 1963. Last previous edition approved in 2012 as D2230 96 (2012).DOI: 10.1520/D2230-17.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orc
15、ontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Glossy prints of Figs. 3 and 4 are available at a nominal cost from ASTMInternational Headquarters. Order Adjunct No. ADJD2230. Origi
16、nal adjunct pro-duced in 1986.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United StatesThis international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principl
17、es for theDevelopment of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.1the die to contour the interior of the extruder head. This willreduce turbulent flow of the rubber.5.4 ExtruderA screw-type laboratory extr
18、uder having ascrew diameter of 50 mm or less and which will accommodatethe specified die may be used. The distance between the end ofthe screw and the die shall be from 1 to 2 times the diameterof the screw, the ratio of the length to diameter of the screwshall be 5:1 or greater, and the compression
19、 ratio shall be 1:1.The use of breaker plates, screens, or spiders in the extruder isnot recommended. Solid or hollow screws are acceptable;however, fluid temperature shall be controlled in hollowscrews.Dimension mm in. Dimension mm in.A 7.62 0.300 K 13.33 R 0.525 RB 6.60 0.260 L 3.56 0.140C 4.44 0.
20、175 M 3.301 R 0.130 RD 7.24 0.285 N 0.32 R 0.013 RE 7.62 0.300 O 20.32 R 0.800 RF 13.97 R 0.550 R P 0.25 R 0.010 RG 2.16 0.085 Q 3.56 0.140 RH 1.90 0.075 R 15.87 Dia 0.625 DiaI 3.05 0.120 S 0.13 0.005J 0.51 0.020 T 4.06 0.160Tolerance, 60.025 mm (60.001 in.)Area, 50 mm2(0.0776 in2)Thickness of die,
21、5 6 2.0 mm (0.197 6 0.79 in.)FIG. 1 ASTM Extrusion Die, Garvey TypeFIG. 2 Diagram Showing Stock Flow from End of Screw to ASTMExtrusion DieD2230 1725.4.1 The extruder shall be equipped with devices capableof monitoring the temperature of the barrel, the head, thedischarged heating fluid from the scr
22、ew, and the surface of thedie. These monitoring devices shall have a sensitivity of60.5C (1F).5.5 Take-away ConveyerA motor-driven belt conveyor atleast 150 mm (6 in.) wide, at least 1.5 m (5 ft) long and variablein speed up to at least 75 mm/s (15 ft/min).5.6 Pyrometer or Equivalent Instruments, wi
23、th a sensitivityof 60.5C (1F) for measuring mill rolls and die surface.6. Materials: Standard Recipes6.1 The appropriate formulas and mixing procedures de-scribed in Test Methods D3187 for NBR and Test MethodsD3185 for SBR shall be used for preparing the standardcompound and test compound. The stand
24、ard compound se-lected from Test Methods D3187 and D3185 should be assimilar as possible to the test compound formulation. Thestandard compound is used to determine the proper combina-tion of extrusion test conditions for evaluating the test com-pounds.6.2 The standard compound shall be mixed using
25、the currentIndustry Reference Carbon Black (IRB) and either SBR 1500or NBR standard polymers as required. If a different compo-sition is to be evaluated, the reference and test compounds shallbe prepared by the same recipe.NOTE 2If two batches must be blended to obtain sufficient materialfor a test,
26、 it is imperative that all mixes within a set receive equaltreatment, as extrusion characteristics change with milling or otherworking.7. Temperatures7.1 Mill Roll Temperature, 50 6 5C (122 6 9F) shall beused for warm-up.7.2 Screw Fluid Temperature (if equipped for control), 4065C (104 6 9F).7.3 Bar
27、rel Temperature, 70 6 10C (158 6 18F).7.4 Head Temperature, 110 6 15C (230 6 27F).7.5 Die Temperature, 110 6 15C (230 6 27F). The dietemperature may be allowed to reach equilibrium by conduc-tion or through application of external heat.7.6 The temperature ranges given in 7.2 7.5 are the rangeswithin
28、 which screw, barrel, head, and die temperatures may bevaried. The constancy of temperature, once set, should be62C.NOTE 3Certain rubbers may require temperatures for processing thatdo not fall within these limits. Individual adjustment must be made inthese cases.8. Procedure8.1 Weigh approximately
29、1 kg of standard compound andwarm up on the mill. The amount of stock required depends onthe size of the extruder. Set the mill rolls to form a rolling bank.Warm up the stock by banding it on the mill, and then cut thebatch from side to side at 30-s intervals for 4 min. Record thestock temperature a
30、t the end of the warm-up operation.8.2 Set the rotational speed of the screw to 4.7 rad/s (45r/min). If the extrusion is not smooth, higher screw speeds maybe tried until a smooth delivery is obtained. Once the screwspeed is established, it will remain unchanged during theevaluation of the samples b
31、eing tested.8.3 Position the take-away conveyor so that the verticaldistance of the belt below the die opening does not exceed 25mm (1 in.) and the belt is centered below the extruder dieopening.8.4 Remove the die and remove all stock from the die andextruder head. Replace the die and immediately pr
32、oceed withthe following steps.8.5 Remove the stock from the mill in a continuous strip 3to 5 mm (0.12 to 0.20 in.) thick, adjusting the width to fit theflight width of the feed section of the screw. Feed the strip intothe extruder hopper until the barrel is full and the rubber beginsto extrude throu
33、gh the die. While continuing to feed theextruder, take the extrusion from the die by the take-awayconveyor. Avoid stretching the extrusion.8.6 By observation, determine when the extrusion hasreached a stable condition. Measure the die temperature toensure that it has again stabilized at the set poin
34、t. Select aspecimen approximately 250 mm (10 in.) in length that isrepresentative of the stable extrusion.8.7 Rate the extrusion by System A or B, described in 9.1and 9.2, respectively.8.8 If the rating for the standard compound is notacceptable, adjust the extrusion temperatures within the pre-scri
35、bed limitations in Section 7 and repeat the test on newbatches of the standard compound until a rating of 4,4,4,4 bySystem A, or 10A by System B, is achieved. Once theseconditions are established, do not change them during theevaluation of the test compounds. If temperature changes arenot successful
36、, then try higher screw speeds as described in 8.2.8.9 Warm up the sample mix as described in 8.1 and repeat8.4 8.7 for the test or experimental rubber compounds, usingthe extrusion conditions established in 8.8.8.10 If specimens are to be saved for reference purposes,rest them for 1 h with ends sec
37、ured and then cure in open steamwith ends secured.9. Rating Systems9.1 System AThis system is based on four separategradings, each grading represented by a digit. The first digit inthe rating refers to swelling or porosity, the second digit refersto sharpness and continuity of the 30 edge, the third
38、 digitrefers to smoothness of the surface, and the fourth digit refersto sharpness and continuity of corners. The ratings range from1 (poor) to 4 (excellent) (see Fig. 3).39.2 System BIn this system, a combination of a digit anda letter of the alphabet is used to grade extrusions. The number,ranging
39、 from 1 (poor) to 10 (excellent), rates the sharpness andcontinuity of the 30 edge; the letter, ranging from A (excel-lent) to E (poor), rates the smoothness of the surface (see Fig.4).3D2230 17310. Report10.1 Report the following information:10.1.1 Stock identification.10.1.2 Extrusion conditions a
40、s follows:10.1.2.1 Stock temperature at end of warm-up,10.1.2.2 Screw temperature,10.1.2.3 Barrel temperature,10.1.2.4 Head temperature,10.1.2.5 Die temperature, and10.1.2.6 Screw rotational speed, (or angular speed), rad/s(r/min).10.1.3 Rating of the extrusion by either System A or SystemB, or both
41、.11. Precision and Bias11.1 A precision statement is not directly applicable sinceboth Systems A and B yield only qualitative comparison datafor a candidate test compound versus a standard compound.FIG. 3 Appearance Ratings by Rating System AFIG. 4 Appearance Ratings by Rating System BD2230 17411.2
42、Since no accepted reference values can be determinedor theoretically calculated, no estimation of bias can be made.12. Keywords12.1 appearance; extrudability; extrusion; processabilityASTM International takes no position respecting the validity of any patent rights asserted in connection with any it
43、em mentionedin this standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This standard is subject to revision at any time by the responsible technical com
44、mittee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a
45、meeting of theresponsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor Driv
46、e, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org). Permission rights to photocopy the standard may also be secured from the Copyright Clearance Center, 222Rosewood Drive, Danvers, MA 01923, Tel: (978) 646-2600; http:/ 175
