1、Designation: D3982 08 (Reapproved 2014) An American National StandardStandard Specification forContact Molded “Fiberglass” (Glass Fiber ReinforcedThermosetting Resin) Ducts1This standard is issued under the fixed designation D3982; the number immediately following the designation indicates the year
2、oforiginal adoption or, in the case of revision, the year of last revision. 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 specification covers ducts fabricated by contactmold
3、ing intended for use in handling corrosive fumes andprocess gases. Special attention is given to equipment thatoperates at temperatures over 180F (82.2C) with regard tostrength and corrosion resistance.1.2 The material of construction shall be “fiberglass” con-sisting of a polyester, vinyl ester, or
4、 other qualified resin-matrixsystems with fiber reinforcement in accordance with Specifi-cation C582.1.3 This specification is not intended to cover selection ofresins and reinforcements for specific chemical environments.1.4 This specification covers ducts up to a design pressureof 65 psig (34.5 Pa
5、).1.5 The values stated in inch-pound units are to be regardedas standard. The values given in parentheses are mathematicalconversions to SI units that are provided for information onlyand are not considered standard.1.6 This standard does not purport to address all of thesafety concerns, if any, as
6、sociated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.NOTE 1There is no known ISO equivalent to this standard2. Referenced Documents2.1 ASTM Standards:2
7、C581 Practice for Determining Chemical Resistance ofThermosetting Resins Used in Glass-Fiber-ReinforcedStructures Intended for Liquid ServiceC582 Specification for Contact-Molded Reinforced Thermo-setting Plastic (RTP) Laminates for Corrosion-ResistantEquipmentD883 Terminology Relating to PlasticsD2
8、583 Test Method for Indentation Hardness of Rigid Plas-tics by Means of a Barcol ImpressorD2584 Test Method for Ignition Loss of Cured ReinforcedResinsF412 Terminology Relating to Plastic Piping SystemsF436 Specification for Hardened Steel Washers2.2 NFPA Standard:NFPA 91 Installation of Blower and
9、Exhaust Systems forDuct, Stack and Vapor Removal or Conveying33. Terminology3.1 Definitions:3.1.1 The definitions used in this specification are in accor-dance with definitions in Terminologies D883 and F412, unlessotherwise specified.3.2 Definitions of Terms Specific to This Standard:3.2.1 calculat
10、ed thicknessthis description is in accordancewith the standard laminate composition tables for Types I andII in Specification C582.3.2.2 contact moldingincludes the “hand layup” and the“spray up” methods of manufacture.3.2.3 flange cantthe angle that an entire branch is off frombeing perpendicular t
11、o the main run centerline (see Fig. 1).3.2.4 flange flatnessmaximum deviation, (see Fig. 2) fromthe actual flange face not including warpage or perpendicular-ity.3.2.5 flange offsetthe amount that an entire branch is offthe main run centerline (see Fig. 3).3.2.6 flange perpendicularitymaximum angle
12、that theplane (see Fig. 2) of the flange inside diameter makes with theperpendicular plane to the ducts centerline.3.2.7 flange warpagethe amount that a flange outsidediameter pulls back from the plane of the inside diameterduring the cure of the material (see Fig. 2).1This specification is under th
13、e jurisdiction of ASTM Committee D20 onPlastics and is the direct responsibility of Subcommittee D20.23 on ReinforcedPlastic Piping Systems and Chemical Equipment.Current edition approved March 1, 2014. Published March 2014. Originallyapproved in 1981. Last previous edition approved in 2008 as D3982
14、 08. DOI:10.1520/D3982-08R14.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Available from National Fire Pr
15、otection Association (NFPA), 1 BatterymarchPark, Quincy, MA 02169-7471, http:/www.nfpa.org.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States13.2.8 hand layupapplication of glass plies in sheet formby hand. Resin can be applied by either
16、 brushing, rolling, orspraying.3.2.9 minimum thicknesstake six thickness readings. Theaverage of the six readings shall be a minimum of 85 % of thecalculated thickness. This must contain the required layers ofglass.3.2.10 spray upfiberglass roving is chopped and blownonto the mold in conjunction wit
17、h resin and catalyst.3.3 Symbols:3.3.1 M =112 oz/ft2chopped-strand mat.3.3.2 R = 24 oz/yd2woven-roving witha5by4weave.3.3.3 V = glass or synthetic veil, 0.010 in. (0.25 mm)calculated thickness.3.3.4 For additional symbols and abbreviations specific todesign requirements, see 6.2.1.4. Materials and M
18、anufacture4.1 ResinThe resin used shall be a commercial-gradethermoset that has either been evaluated in a laminate by test inaccordance with Practice C581 or that has been determined byprevious documented service to be acceptable for serviceconditions. Where service conditions have not been evaluat
19、eda suitable resin may be selected by agreement between themanufacturer and the end user.4.1.1 The resin may contain fillers or pigments in accor-dance with Specification C582.4.1.2 Athixotropic agent may be added up to 5 % by weightof resin.NOTE 2The addition of a thixotropic agent may reduce the r
20、esistanceof many resin systems to certain corrosive chemical environments. It is theresponsibility of the fabricator, using a thixotropic agent in the resin toascertain its compatibility with the corrosive environment when this hasbeen reported to him by the purchaser.4.1.3 Fire-retardant additives
21、may be added to resins ifrequired to reduce flame spread.NOTE 3The addition of fire-retardant agents may interfere with thevisual inspection of laminate quality. Use in the inner surface and interiorlayer should consider this, and the need for fire retardance should outweigh any potential visual ins
22、pection difficulties. In some cases fire-retardant agents can also affect the the chemical resistance of the resin. Ifthis is suspected, then chemical resistance testing of the resin should beconducted with fire-retardant additives included. Again the need for fireresistance should be balanced with
23、chemical resistance.4.2 ReinforcementGlass reinforcing material with a binderand sizing compatible with the resin to be used. Fiber rein-forcements shall be in accordance with, and meet the require-ments of, Specification C582 including composition require-ments for Type I and Type II laminates.4.2.
24、1 Corrosion BarrierConsists of the inner surface fol-lowed by the interior layer. The corrosion barrier has aminimum total calculated thickness of 0.096 in. (2.4 mm).4.2.1.1 Inner SurfaceSurfacing veil with approximately90 % resin and 0.010 to 0.020-in. (0.25 to 0.50-mm) calculatedthickness.4.2.1.2
25、Interior LayerA minimum of two plies of 112oz/ft2chopped-strand mat or chopped roving equivalent witha compatible sizing system with approximately 75 % resin andFIG. 1 Flange CantFIG. 2 Flange Tolerance DescriptionFIG. 3 Flange OffsetD3982 08 (2014)20.086-in. (2.2-mm) calculated thickness minimum. F
26、iberlength shall be12 in. (12.7 mm) minimum to 2 in. (50.8 mm)maximum.4.2.2 Structural LayerShall consist of chopped-strand matplies of nominally 112 oz/ft2and have a12 in. (12.7 mm)minimum to 2 in. (50.8 mm) maximum fiber length, or shallconsist of a chopped roving equivalent in the spray-up method
27、.When necessary, woven-roving plies shall be used and shallconsist of 24 oz/yd2with a five by four weave or a suitableequivalent agreed on by the end user and the fabricator.Woven-roving shall be applied alternately with a minimum ofa112 oz/yd2mat or chopped roving equivalent, finishing witha mat la
28、yer.4.2.3 Outer SurfaceShall be coated with a resin-rich layerand containing 0.2 to 0.6 % paraffin wax with a melting pointof 122 to 126F (50.0 to 52.2C), except when other means areused to prevent air inhibition.5. Physical Properties5.1 Minimum wall of (V, M, M, M) shall be maintainedunder any cir
29、cumstances.5.2 Laminates or portions of laminates comprised only ofchopped-strand mat shall have a 25 to 30 % glass content byweight when tested by Test Method D2584.5.3 Minimum mechanical properties of standard laminatesshall be in accordance with Specification C582.6. Design Requirements6.1 Design
30、 Limitations:6.1.1 Safety FactorUse five for external pressure, use tenfor internal pressure and all other design calculations.6.1.2 Maximum Permissible Deflection Under DesignLoadUse 1 % of the span for laminates not exposed to achemical environment and use12 % of the span for allowabledeflection w
31、hen a chemical environment will be in contact withthe laminate.6.1.3 Secondary Bond StrengthWhen the load is along thesurface, use 2000 psi (13.79 MPa) ultimate shear stress for thebonding surface area. Use a safety factor of ten when calcu-lating allowable secondary bonding stresses.6.1.4 When an e
32、xtra corrosion barrier is specified, do notinclude this thickness in the design calculations.6.1.5 Increase all calculated wall thicknesses to the neareststandard wall thickness. Treat these standard wall thicknessesas minimum dimensions.6.2 Cylinder Wall Design:6.2.1 Symbols and Abbreviations:6.2.1
33、.1 PActual design pressure, psi (MPa).6.2.1.2 PAAllowable pressure, psi (MPa).6.2.1.3 DoOutside diameter of cylinder, in. (mm).6.2.1.4 DInside diameter of cylinder, in. (mm).6.2.1.5 SUltimate tensile strength, psi (MPa).6.2.1.6 FSafety factor (see 6.1.1).6.2.1.7 TCylinder wall thickness, in. (mm).6.
34、2.1.8 ETensile modulus of elasticity, psi (MPa).6.2.1.9 LCylinder length between joints or elements thatqualify as a stiffener, in. (mm).6.2.1.10 IRequired moment of inertia for an element toqualify as a stiffener, in.3(mm3).6.2.2 Internal Pressure:T 5PDF2S6.2.3 External Pressure (Internal Vacuum):C
35、alculate:1.73SDoTD0.5If result:,LDoThen use:P 52.2EFSTDoD3If result:$LDoThen use:P 52.6EFSTDoD2.5LDo2 0.45STDoD0.56.2.4 Stiffeners to Withstand External Pressure:6.2.4.1 Required Moment of Inertia:I 5PL Do!3F24E6.2.4.2 Material used to attach ring stiffener to cylinder wallmay be included when calcu
36、lating the actual moment of inertiaof the stiffener as well as the portion of the cylinder wallbeneath the stiffener and attachment material up to a width of2x (stiffener width).6.3 Rectangular Duct:6.3.1 The largest flat panel shall be designed to withstandthe loading conditions and not exceed the
37、design limitations(see 6.1.2). This can be accomplished with a sufficient wallthickness alone or by the incorporation of stiffening ribs toreduce the required wall thickness.6.3.2 Appropriate calculations shall be performed for wallthickness and stiffening ribs as determined by the manufacturerand t
38、he purchaser. Minimum wall thickness in all cases forrectangular duct shall be as in Table 1, substituting the longerside for the diameter.6.3.3 The radial sides of a rectangular elbow shall bedesigned as a round cylinder with the same radius.6.4 Follow the requirements of NFPA 91Bulletin, Section51
39、0 when it is required by law or the engineer.6.5 Shop Drawings and Design CalculationsThe fabri-cated structure shall be in accordance with the design andconstruction details shown on shop drawings and designD3982 08 (2014)3calculations prepared by the manufacturer and approved by thepurchaser. Deta
40、ils to be covered include, but are not limited to,the following:6.5.1 Materials, including a definition of the fiber-resinsystem, in accordance with types of resins and reinforcingmaterials of Specification C582,6.5.2 Dimensions,6.5.3 Size and location of stiffening ribs,6.5.4 Location of field join
41、ts and flanges, and6.5.5 Type and location of supports, if supplied by themanufacturer.6.6 All stiffeners, access openings, lifting devices or otherappurtenances shall be included as part of the duct design.6.7 Where static electricity has been determined to be aproblem by the engineer, the inner su
42、rface of the ductworkshall be grounded with a maximum resistance to ground of106. The grounding method shall be determined by themanufacturer and the purchaser.7. Dimensions7.1 Standard duct and fitting dimensions are shown on Fig.4 and are based on inside dimensions.7.2 Standard elbows shall have a
43、 centerline radius of 112times the duct diameter for over 3-in. (76.2-mm) diameter andtwo times the duct diameter for 3-in. diameter and under.7.3 Mitered joints on all elbows 24-in. (609.6-mm) diameterand under are not permitted except when more room is requiredfor bolting or when a diameter is cho
44、sen that is not shown onTable 1.7.4 Standard duct flange thickness, drilling patterns, andminimum wall thickness are shown in Table 1.7.4.1 Vent connections from tanks and fans are normallydifferent from this pattern. Appropriate adjustments to flangedimensions need to be taken to effect transition.
45、7.5 To determine minimum information for rectangularduct, use the longest side and increase to the nearest standardround-duct inside diameter. This diameter can be used todetermine the flange thickness, minimum wall thickness andbolt-hole diameter, or tolerances.7.6 There is no standard drilling pat
46、tern for rectangular duct.Bolt-hole spacing shall be designed for a proper seal with amaximum spacing of 412 in. (114.3 mm).7.7 All bolt holes straddle major centerlines unless other-wise specified.8. Tolerances8.1 Terminology for tolerances is given in 3.2.8.2 Out of Roundness:TABLE 1 Typical Flang
47、e Dimensions and Hanger SpacingNOTE 11 in. = 25.4 mm1 lb/ft = 1.488164 kg/m.InsideDiameter, in.CalculatedAWallThickness,in.CylinderAWallConstructionFlangeBThickness,min, in.FlangeOutsideDiameter, in.Flange BoltCircle, in.Bolt HoleDiameter, in.Number BoltHolesRecom-mended BoltTorque, ft/lbMaximumBolt
48、 Torque,ft/lbMaximumCDHangerSpacing, ft1 0.14 Type I38 538 4716 420308.0114 0.14 Type I38 558 414716112 0.14 Type I38 578 412716 420308.52 0.14 Type I12 638 5716 54212 0.14 Type I12 678 512716 42 09.03 0.14 Type I12 738 6716 54 54 0.14 Type I12 838 7716 4 25 40 10.06 0.14 Type I12 1038 9716 8 25 40
49、10.58 0.14 Type I12 1238 11716 82541.010 0.14 Type I12 1438 13716 12 25 40 11.512 0.14 Type I12 1638 15716 12 25 40 11.514 0.14 Type I12 1838 17716 12 25 40 12.016 0.14 Type I12 2038 19716 16 25 40 12.518 0.14 Type I12 2238 21716 16 25 40 12.520 0.14 Type I12 2438 23716 20 25 40 13.024 0.18 Type I12 2838 27716 20 25 40 15.030 0.18 Type I58 3438 33716 28 35 50 15.536 0.18 Type I58 4038 39716 32 35 50 16.042 0.22 Type II58 4638 45716 36 35 50 19.048 0.22 Type II58 543
