1、 This document is restricted and may not be sent outside Navistar, Inc. or reproduced without permission from Corporate Technical Standards. Suppliers are required to assume all patent liability. 2014 by Navistar, Inc. APRIL 2014 Page 1 of 12 NAVISTAR, INC. Material, Parts, and Process Specification
2、s (MPAPS) NUMBER: MPAPS A-1044 Former Designation: TMS-1044 TITLE: Tapered Leaf and Main Support Member Suspension Springs CURRENT REV No.: 1404 DATE: April 2014 WRITTEN/EDITED BY: Materials Engineering APPROVED BY: Materials Engineering SUPERSEDES: Rev. 1312 December 2013 PRINTED COPIES OF THIS DOC
3、UMENT MUST BE VERIFIED FOR CURRENT REVISION This specification may involve hazardous materials, equipment, and procedures. This specification does not purport to address all of the safety issues associated with its use. The user is responsible to consult appropriate safety and health practices and t
4、o determine the applicability of regulatory limits prior to use. Change Notice: Changed to new MPAPS format; depth of decarburization determination method updated; editorial changes. 1.0 APPLICATION This specification covers steel tapered leaf suspension springs and Main Support Member (MSM) suspens
5、ion springs. 2.0 SCOPE This specification covers requirements for material, dimensional tolerances, KCC, heat treatment, microstructure, post-hardening treatments, validation, source approval/quality control, shipping, and identification. 2.1 Restricted Chemical Substances Effective January 1, 2007,
6、 all product supplied to the requirements of this specification must comply with the requirements of the MPAPS B-50 specification. 3.0 REFERENCE DOCUMENTS Unless otherwise specified the latest issue of all referenced standards shall apply. The following Specifications, Standards, and Regulations are
7、 referenced in this specification. Quality System Standard ISO 9001 or TS-16949 NAVISTAR TMS-4516 ASTM E 112 CFR Title 29, Part 1910 NAVISTAR CEMS GT-4D ASTM E 1382 NAVISTAR Engineering Design Std. A-16 NAVISTAR CEMS GT-5A ASTM E1077 NAVISTAR Manufacturing Std. MS-D-13 NAVISTAR CEMS GT-7D SAE J400 N
8、AVISTAR MPAPS A-0, Part I NAVISTAR CEMS GT-14C SAE J422 NAVISTAR MPAPS A-0, Part III ASTM A 29 SAE J510 NAVISTAR CEMS A-39 NAVISTAR MPAPS B-50 SAE J788 4.0 REQUIREMENTS 4.1 Material Open hearth, basic oxygen or electric furnace, ingot cast or strand cast, steel may be used. Unless otherwise specifie
9、d, the general requirements for steel as described in ASTM A 29 shall be applicable. Steel supplied shall be fully killed, made to fine grain practice, and shall meet the minimum Steel Cleanliness Requirements for Quality Level I per MPAPS A-0, Part I. NUMBER: MPAPS A-1044 TITLE: Tapered Leaf and Ma
10、in Support Member Suspension Springs REVISION: 1404 This document is restricted and may not be sent outside Navistar, Inc. or reproduced without permission from Corporate Technical Standards. Suppliers are required to assume all patent liability. 2014 by Navistar, Inc. APRIL 2014 Page 2 of 12 4.2 Ch
11、emical Composition TAPERED LEAF SPRINGS MAIN SUPPORT MEMBER SPRINGS Carbon 0.66% max Carbon 0.65% max Silicon 0.35% max Silicon 0.35% max Phosphorus 0.040% max Phosphorus 0.025% max Sulfur 0.050% max Sulfur 0.035% max Alloy elements as required Alloy elements as required 4.3 Heat Treatment Springs s
12、hall be hardened and tempered at 425C (800F) minimum. Material type to be specified in the drawing notes. 4.3.1 Tapered Leaf suspend at 250,000 cycles. Monoleaf springs with eyes on both ends have been developed as direct replacements of leaf springs. This particular spring also type falls into this
13、 category. 4.9.3.5 Vertical Test Method Main Support Members Clamp assembly and cycle from 0.25 to +2.25 G (G, minimum = rated load at the wheel (minus the unsprung weight). Bump stops or auxiliary springs should be used during validation, if they are intended to engage below 2.25gs. 4.9.1.6 Vertica
14、l Pass-Fail Criteria Main Support Members Unless otherwise specified, assemblies shall exhibit a minimum B10 life of 110 000 cycles without failure* when tested as indicated. (*Failure is defined as fracture of any leaf/component.). Pass-Fail Criteria is B10 110,000 cycles; suspend at 250,000 cycles
15、. 4.9.2 Combined Vertical suspend at 250,000 cycles. Furthermore the cumulative measured free camber loss must be less than 12mm after the completion of Stage II relative to the pre-test measurement. Monoleaf springs with eyes on both ends have been developed as direct replacements of leaf springs.
16、This particular spring also type falls into this category. 4.9.2.3 Combined Vertical & Braking Sample Size For new parts, 6 samples shall be tested for initial qualification, unless validated under similar design. For parts with prior production history, 3 samples shall be tested. 5.0 QUALITY Surfac
17、e of the leaves shall exhibit no visual evidence of significant discontinuities such as laps, scale, scabs, and slivers, and shall exhibit no transverse tool marks or gouges. (Transverse is defined as being perpendicular to the length of the leaf within an angle of 15 from the perpendicular.) Surfac
18、e discontinuities such as pits, longitudinal tool marks or gouges and other depressions are permissible provided they are not deeper than 0.25 mm (0.010 in) and that they do not have a sharp radius root radius to be less than 0.75 mm (0.030 in). Leaves shall also be free from pipe, bursts, and lamin
19、ations. Maximum depth of seams shall be 0.02 mm (0.001 in) per 1.6 mm (0.06 in) thickness (at the point of measurement). 5.1 KCC - Quality Control Plan A Quality Control Plan for this product will be established by mutual agreement between NAVISTAR and the supplier. The following five (5) characteri
20、stics, where applicable*, shall be included in the plan as features for management by statistical process control*. 1. Width at the leaf ends 2. Pack width at points 3.0 0.1 inch on either side of the spring center. 3. Center bolt height above the main leaf 4. Finished bushing ID or thread pitch dia
21、meter 5. Spring loaded height (in the case of springs sorted by Method B) * Additional characteristics for inclusion in the Control Plan may be specified on the engineering drawing or purchase order. * See Engineering Design Standard A-16. 6.0 SOURCE APPROVAL AND QUALITY CONTROL 6.1 Supplier Require
22、ments All suppliers to NAVISTAR are required to be registered to ISO 9001 Quality System Requirements. NAVISTAR will also accept TS-16949 registration as long as the supplier can also fulfill all AIAG PPAP (Production Part Approval Process) documentation and approval requirements. Suppliers must mai
23、ntain their certification with an accredited registrar and must furnish copies of registration certificates to their Corporate Buyer upon request. NUMBER: MPAPS A-1044 TITLE: Tapered Leaf and Main Support Member Suspension Springs REVISION: 1404 This document is restricted and may not be sent outsid
24、e Navistar, Inc. or reproduced without permission from Corporate Technical Standards. Suppliers are required to assume all patent liability. 2014 by Navistar, Inc. APRIL 2014 Page 10 of 12 6.2 Approval Parts supplied against contracts or purchase orders citing this specification shall be equivalent
25、in all respects to those samples that were approved by the purchaser. No changes in formulation or processing practices are permitted without approval. In the event that changes in material, properties, processing practices, construction, color, or labeling of the product are required, the supplier
26、shall notify NAVISTAR Materials Engineering and Purchasing and Supplier Development of the proposed change(s). Test data indicating conformance to all requirements of this specification, test samples, and new or amended or updated Material Safety Data Sheets (MSDS), in accordance with CFR Title 29,
27、Part 1910, shall be submitted with the request for change. 6.3 Process Control The supplier shall either perform and report results of tests on specific lots of parts produced using ISO 9001 or TS-16949 guidelines, or provide statistical evidence of the lot having been produced in a state of statist
28、ical control and with a process capable of providing all required properties. The part supplier and the quality control manager of the using NAVISTAR plant may determine testing and reporting requirements on specific products. 6.4 Approved Material Suppliers 6.4.1 Steel Steel for Main Support Member
29、s (Control Arm Springs) will be provided by ArcelorMittal. Steel supplied will have a minimum reduction ratio of 6:1 and a chemical composition and production practice capable of providing the required fine grain size and with sufficient hardenability to meet all mechanical property requirements. 6.
30、4.2 Corrosion Protection Coatings Approved sources of corrosion protective coatings are shown in the table below. 1) Ionoklad 200L 2) Zinky 101E 4) TMS-4516, Type IV United Paint & Chemical 3) TMS-4516, Type IV Tectyl 300G Black (3.4) 24671 Telegraph Road Hunting 4601 Daubert Chemical Company Southf
31、ield, MI 48075 Hunting Industrial Coatings 4700 S. Central Ave. (313) 353-3035 10448 Chester Road Chicago, IL 60638 Cincinnati, OH 45215 7.0 SHIPPING, PACKING AND IDENTIFICATION Loading, packing and identification shall be in accordance with Manufacturing Std. MS-D-13. 7.1 Identification Springs sha
32、ll be marked, stamped, or engraved, on the top-central-portion of the spring eye, prior to heat treatment, in clearly legible block capital letters, not less than 6 mm high with the following information: 7.1.1 Part Number: Each part shall be identified with the Navistar part number. 7.1.2 Date or B
33、atch Code: A code with traceability back to the date of manufacture, the specific batch of parts and the heat of steel shall be included in the identification of each part. The specific code or identification to be used by each supplier shall be agreed upon between the Quality Manager of the using N
34、avistar plant and the supplier. NUMBER: MPAPS A-1044 TITLE: Tapered Leaf and Main Support Member Suspension Springs REVISION: 1404 This document is restricted and may not be sent outside Navistar, Inc. or reproduced without permission from Corporate Technical Standards. Suppliers are required to ass
35、ume all patent liability. 2014 by Navistar, Inc. APRIL 2014 Page 11 of 12 8.0 DESIGNATION ON DRAWINGS The drawing must designate in the notes: “This part complies with MPAPS A-1044” o If the spring has multi-leaf AND taper-leaf elements (such as the case with a taper MSM with a flat secondary redund
36、ancy) the notes are to designate which part(s) complies with MPAPS A-1037 and which part(s) complies with MPAPS A-1044. Any exception to compliance with the TMS must be noted in the drawing All drawings must specify the following o Weight o Free State Geometry o Rated Load o Maximum Allowable Deflec
37、tion o Spring Rate Clamped o Spring Rate Unclamped o Load vs. Deflection Curve o Camber Management Table o Brake test requirement, if used w/ high torque Reduced Stopping Distance (RSD) brakes BOM is to include all components that are serviceable Supplier must provide CAD geometry in Parasolid or UG
38、 format for springs deflected to all of the following five conditions: 1. Unloaded free state 2. Deflected at rated 1g load condition 3. Deflected at maximum allowable deflection condition 4. Deflected at free hang condition Based on free state plus 0.1g unsprung mass hanging from the spring in a wh
39、eel lift-off condition. 5. Deflected at brake wind-up condition (provide this only if applied with RSD brakes) Based on maximum expected brake torque to slip calculated by: Maximum Brake Torque = Tmax = (Fs * Load Transfer)* ) * SLR o Where: Fs = Static load at the ground (lb) = Capacity/2. Load Tra
40、nsfer = Vertical load multiplier for load transfer under braking. For forward braking let this be 1.6. = Coefficient of friction. Let this be 0.755 SLR = Static Loaded Radius of tire (in). Let this be 20.5 in. Note: The resulting Tmax correlates well with physical testing Example: Let Capacity = 12,
41、350 lb Thus Fs = 6,175 lb Tmax = (Fs * Load Transfer)* ) * SLR = (6175 lb * 1.6)* 0.755) * 20.5 in = 153,000 in-lb NUMBER: MPAPS A-1044 TITLE: Tapered Leaf and Main Support Member Suspension Springs REVISION: 1404 This document is restricted and may not be sent outside Navistar, Inc. or reproduced w
42、ithout permission from Corporate Technical Standards. Suppliers are required to assume all patent liability. 2014 by Navistar, Inc. APRIL 2014 Page 12 of 12 9.0 TECHNICAL INFORMATION For further information related to the technical content of this specification, contact: Suppliers may purchase contr
43、olled copies of this specification by contacting: Materials Engineering and Technology Dept. 10400 W. North Ave. Melrose Park, IL 60160 E-mail: MaterialsEngineeringN IHS Global Inc. 15 Inverness Way East Englewood CO 80112-5776 Phone: 1-800-854-7179 E-mail: AutomotiveIHS.com Website: http:/ GENERAL
44、INFORMATION (Not a Requirement) Steels suggested for the thinner sections are 15B62, 50B50H, 5155H, 5160H, 6150H, and 8650H. Steels for heavier sections are: 4150H, 50B60H, 51B60H, and 4161H. The steel should be selected which will meet the required harden ability at minimum cost. To meet the surface quality requirements for decarburization, intergranular oxidation, and seam depth, it is permissible to grind the tension side of the leaf prior to hardening.
