M7-13 FABRICATION STANDARDS COMMUNICATIONS & POWER INDUSTRIES LLC MICROWAVE POWER PRODUCTS DIVISION Revision: AV ECO: MPP615849 May 16, 2016 Spec. No.: M7-13 FABRICATION STANDARDS ECO: MPP615849 Rev. AV Date: May 16, 2016 MANUFACTURING SPECIFICATION Page i of iii TABLE OF CONTENTS PREFACE................................................................................................................................................... 1 REFERENCES ........................................................................................................................................... 1 DEFINITIONS ............................................................................................................................................. 1 1.0 RAW MATERIALS ........................................................................................................................... 2 2.0 STANDARDS FOR RAW-MATERIAL MACHINING ALLOWANCES............................................... 3 3.0 4.0 5.0 6.0 2.1 Minimums ............................................................................................................................. 3 2.2 Calculation of Raw-Material Dimensions............................................................................... 3 2.3 Tubing .................................................................................................................................. 4 CERTIFICATION.............................................................................................................................. 4 3.1 When Certification is Required ............................................................................................. 4 3.2 Delivery or Storage of Certifications ..................................................................................... 4 3.3 Requirements on All Certifications ........................................................................................ 4 3.4 Certification Types ................................................................................................................ 5 PACKAGING AND LABELING ........................................................................................................ 5 4.1 Parts Protection in Packing ................................................................................................... 5 4.2 Transportation ...................................................................................................................... 6 4.3 Package Labeling ................................................................................................................. 7 GEOMETRIC DIMENSIONING AND TOLERANCING SYSTEM ..................................................... 7 5.1 Unspecified Tolerance .......................................................................................................... 7 5.2 Unspecified Finish ................................................................................................................ 8 5.3 Unspecified Flatness ............................................................................................................ 8 5.4 Unspecified Cylindricity ......................................................................................................... 8 5.5 Unspecified Perpendicularity ................................................................................................ 8 5.6 Unspecified Parallelism ........................................................................................................ 9 5.7 Unspecified Concentricity ..................................................................................................... 9 5.8 Unspecified Position ............................................................................................................. 9 5.9 Unspecified Circularity .......................................................................................................... 9 5.10 Unspecified Countersinks ..................................................................................................... 9 TOOLING ...................................................................................................................................... 10 Communications & Power Industries LLC • Microwave Power Products Division • P.O. Box 50750 • Palo Alto • California • 94303-0750 Spec. No.: M7-13 FABRICATION STANDARDS ECO: MPP615849 Rev. AV Date: May 16, 2016 MANUFACTURING SPECIFICATION Page ii of iii TABLE OF CONTENTS (continued) 7.0 CLEANING, PLATING, AND COATING OF SURFACES .............................................................. 10 8.0 BURRS .......................................................................................................................................... 10 9.0 10.0 8.1 Definition ............................................................................................................................ 10 8.2 Types.................................................................................................................................. 11 8.3 Height ................................................................................................................................. 11 8.4 Removal ............................................................................................................................. 11 8.5 Edges ................................................................................................................................. 12 8.6 Corners............................................................................................................................... 12 8.7 Sheet Metal ........................................................................................................................ 13 THREADS ...................................................................................................................................... 13 9.1 Internal Threads ................................................................................................................. 13 9.2 Threaded Holes .................................................................................................................. 13 9.3 Threaded Parts ................................................................................................................... 14 9.4 Full-Form Threads .............................................................................................................. 14 9.5 Unspecified Thread Class of Fit .......................................................................................... 14 SHEET-METAL PRODUCTS FABRICATION REQUIREMENTS................................................... 14 10.1 Sheet Metal ........................................................................................................................ 14 10.2 Features and Surfaces ....................................................................................................... 14 10.3 Machined Features ............................................................................................................. 15 10.4 Circular Runout ................................................................................................................... 15 10.5 Washer-Type Punching ...................................................................................................... 15 10.6 Flatness .............................................................................................................................. 15 10.7 Parallelism and Perpendicularity ......................................................................................... 16 10.8 Edges and Corners ............................................................................................................. 16 10.9 Stock Thickness after Forming ........................................................................................... 16 10.10 Breakaway .......................................................................................................................... 17 10.11 Burrs ................................................................................................................................... 17 10.12 Burr Symbols and Drawing Callouts ................................................................................... 18 Communications & Power Industries LLC • Microwave Power Products Division • P.O. Box 50750 • Palo Alto • California • 94303-0750 Spec. No.: M7-13 FABRICATION STANDARDS ECO: MPP615849 Rev. AV Date: May 16, 2016 MANUFACTURING SPECIFICATION Page iii of iii TABLE OF CONTENTS (continued) 11.0 12.0 CASTING AND FORGING REQUIREMENTS ............................................................................... 18 11.1 Position............................................................................................................................... 18 11.2 Flatness .............................................................................................................................. 19 11.3 Cleanup .............................................................................................................................. 19 11.4 Mismatch ............................................................................................................................ 19 11.5 Draft ................................................................................................................................... 19 11.6 Repair ................................................................................................................................. 20 EDM FABRICATION REQUIREMENTS ........................................................................................ 20 APPENDIX: Geometric Symbology ............................................................................................... 21 Communications & Power Industries LLC • Microwave Power Products Division • P.O. Box 50750 • Palo Alto • California • 94303-0750 Spec. No.: M7-13 FABRICATION STANDARDS ECO: MPP615849 Rev. AV Date: May 16, 2016 MANUFACTURING SPECIFICATION Page 1 of 21 ATTENTION UNLESS OTHERWISE SPECIFIED ON THE PURCHASE ORDER(S) OR CPI INTERNAL SHOP WORK ORDER(S), CONFORMANCE TO ALL REQUIREMENTS OF THE DRAWING(S) AND SPECIFICATION(S) IS MANDATORY. PREFACE The object of the Fabrication Standards Specification M7-13 is to supplement the design information on CPI drawings for microwave Vacuum Electron Device (VED) assemblies and components. Suppliers and CPI manufacturing units shall be responsible for the implementation of these standards in the performance of work for CPI as outlined in CPI purchase orders and shop work orders. This standard reflects the technical requirements for the Microwave Power Products Division (MPP) of Communications and Power Industries LLC. The previous Section 6.0, “Coolants, Lubricants, and Solvents,” which has been a part of past revisions, is now a separate, subordinate document (M7-179, “Approved Lubricants, Coolants, and Solvents”) to facilitate subsequent revisions. All data therein are still considered flow-down requirements from M7-13. Failure to comply with the requirements contained in the Fabrication Standards may result in the rejection of the material produced. In the event of a conflict between the standards, the drawing, and/or the purchase order, the purchase order shall take precedence, the drawing next, and then the standards. All questions from Suppliers concerning the interpretation of the standards shall be directed to the CPI MPP Purchasing Department. Additional information or revisions shall be provided to Suppliers and all CPI departments engaged in fabrication of piece parts, subassemblies, and finished products. REFERENCES (Latest Revision) 40 CFR, Part 82 ANSI Y14.5 FED-STD-H28 CPI M7-35 CPI M7-179 CPI P0-1 CPI P0-3 CPI P18-2 Protection of Stratospheric Ozone Dimensions and Tolerancing Screw Thread Standards for Federal Services Inventory Packaging Approved Lubricants, Coolants, and Solvents Approved Sources for Raw Materials and Processes (Including Sections 1, 2, 3, and 4) Supplier Quality System Requirements Clean Packaging of Supplier-Provided Parts DEFINITIONS CMM EDM EPA MMC Non-Vacuum Assembly Non-Vacuum Part OFE Coordinate Measuring Machine Electrical Discharge Machining Environmental Protection Agency Maximum Material Condition An assembly that is not within or part of the vacuum envelope A part that is not within or part of the vacuum envelope Oxygen Free Electronic Revision Information Updated Section 3.0 and Geometric Symbology Appendix Spec. No.: M7-13 FABRICATION STANDARDS ECO: MPP615849 Rev. AV Date: May 16, 2016 MANUFACTURING SPECIFICATION PO P-Spec RFS Vacuum Assembly Vacuum Part VED 1.0 Page 2 of 21 Purchase Order Purchasing Specification Regardless of Feature Size An assembly that is within or part of the vacuum envelope A part that is within or part of the vacuum envelope Vacuum Electron Device (modern name for “microwave tube”) RAW MATERIALS The performance of VEDs is critically dependent upon the strict conformance of raw materials to specifications and to proper processing and cleanliness practices. CPI’s products are subjected to numerous high-temperature cycles during their assembly and processing and must still retain highvacuum integrity, strength, and inherent thermal and magnetic properties. To this end, the Supplier shall be required to use ONLY the material specified on the drawing or on the PO to fabricate the required parts. NOTE USE OF UNAUTHORIZED MATERIAL IS NOT ALLOWED. Violations shall result in removal from the Approved Supplier List and possible exposure to consequential damages. Some of the raw materials used by CPI have directional properties resulting from segregation or inclusions that can seriously jeopardize the vacuum integrity of microwave VEDs. For example, Low-carbon steels have regions of high-carbon content. Stainless steels contain sulfide or oxide inclusions. Cupronickel occasionally exhibits slag inclusions. During ingot reduction, these concentrations of impurities are “stretched out” in the rolling or drawing direction, forming “stringers” (i.e., in the plane of flat or sheet stock and on the axis for bar stock). CPI parts that are designed for vacuum applications will always prescribe a material orientation to ensure that a potential stringer leak path will run parallel to the vacuum wall instead of piercing it. Allowable forms are defined in the purchasing specification (P-Spec) and denoted in the materials block of individual drawings by a P-Spec suffix. The “Grain Symbol” GRAIN ( ) may also be used in instances of critical orientation. Sourcing of raw materials shall be in strict accordance with CPI P0-1, “Approved Sources for Raw Materials and Processes.” All raw materials must be positively identified and directly traceable to the certifications that demonstrate the material’s conformance to stated requirements. Surplus material, including remnants, overage, and scrap, that cannot be traced directly to its certifications shall under no circumstances be used to fabricate parts for CPI. Alternate forms of raw materials (i.e., plate, bar, sheet, etc.) may not be substituted without written approval from CPI. It is unallowable to use welded tubing or to roll and weld flat stock unless specifically prescribed in the drawing or PO. It is unallowable to repair parts by welding, plugging, flame spraying, or other methods without written approval from CPI. Spec. No.: M7-13 FABRICATION STANDARDS ECO: MPP615849 Rev. AV Date: May 16, 2016 MANUFACTURING SPECIFICATION 2.0 Page 3 of 21 STANDARDS FOR RAW-MATERIAL MACHINING ALLOWANCES This section prescribes machining allowances for raw materials to ensure the removal of surface defects and oxides. Material with no allowance has been demonstrated to have a useable surface as received. 2.1 Minimums The allowances specified are minimums to be removed from each side. Where greater amounts must be removed, it is recommended that an equal amount be removed from both sides as permitted by available raw-material dimensions. If surface defects are still visible after removal of the machining allowance, the material should not be used at all. 2.2 Calculation of Raw-Material Dimensions The minimum size of the raw material shall be determined as follows: Determine the “Finished” dimension from the print and ADD the following amounts: For Chromium Copper/Chromium Zirconium Copper Alloys (All Forms Except Castings and Forgings) Under 0.250″ Thick 0.251″ to 1.000″ Thick Above 1.000″ Thick 0.020″ from each surface 0.030″ from each surface 0.060″ from each surface For Chromium Copper/Chromium Zirconium Copper Alloys Castings and Forgings Under 0.250″ Thick 0.251″ to 1.000″ Thick Above 1.000″ Thick 0.020″ from each surface 0.10″ from each surface 0.50″ from each surface For OFE Copper (All Forms Except Castings and Forgings) Under 0.250″ Thick 0.251″ to 1.000″ Thick Above 1.000″ Thick None 5% min from each surface 0.062″ from each surface For OFE Copper Castings and Forgings Under 0.250″ Thick 0.251″ to 1.000″ Thick Above 1.000″ Thick N/A N/A 0.50″ from each surface For All Others (Flat Plate and Rectangular Bar) Under 0.250″ Thick 0.251″ to 1.000″ Thick Above 1.000″ Thick None 2% min to each surface 0.020″ min to each surface Under 0.250″ Dia. None For All Others (Round Bar or Rod) 0.251″ Dia. to 1.000″ Dia. Above 1.000″ Dia. 4% min to diameter 0.040″ min to diameter Spec. No.: M7-13 FABRICATION STANDARDS ECO: MPP615849 Rev. AV Date: May 16, 2016 MANUFACTURING SPECIFICATION 2.3 Page 4 of 21 Tubing The raw-material sizes for the OD of tubing shall be calculated in the same way as the round bar diameter. The maximum ID of tubing shall be calculated by DEDUCTING the following amounts from the “Finished” dimension: Under 1.000″ ID None 3.0 Above 1.000″ ID 0.040″ min CERTIFICATION This section defines the items requiring certification as specified by CPI and states the minimum information that must accompany the parts or assemblies. 3.1 When Certification is Required Certifications are required for all raw materials, electrical components, and whenever certifications are indicated by the drawing, PO, or P-Spec. 3.2 Delivery or Storage of Certifications This section defines the instances wherein the Supplier is to include the certification with the shipment. In all cases, the Supplier is to maintain certifications as Quality Records at its facility in accordance with P0-3, “Supplier Quality System Requirements.” 3.2.1 Fabricated Parts, Assemblies, and Processes Certifications shall be sent with shipments when indicated by any of the following: A. Purchase Order B. Drawing C. Purchasing Specification Any of the following phrases, or a similar phrase with the same intent, may be used to indicate that certifications must be supplied with shipments: A. Certification Required B. Certs. Required C. Certified Reports Shall Be Provided with Shipment 3.2.2 Raw-Material Suppliers and Distributors All raw-material certifications will be shipped with the material. 3.3 Requirements on All Certifications The following information must be provided with all certifications: A. CPI Purchase Order Number B. CPI Part Number/Specification Number and Revision Letter C. Quantity or Amount in Shipment Spec. No.: M7-13 FABRICATION STANDARDS ECO: MPP615849 Rev. AV Date: May 16, 2016 MANUFACTURING SPECIFICATION Page 5 of 21 D. Manufacture Lot, Heat, and/or Batch Number 3.4 E. Compliance Statement F. Signature, Title of Company Representative, and Date Certification Types The following information must also accompany these specific products or processes: 3.4.1 Age-Dated/Environmentally Controlled Material A. Material Description and Type B. Storage Conditions NOTE Specific storage conditions other than normal ambient and environment must be stated on the exterior of the package. C. Expiration Date (must also appear on each container of the product itself) 3.4.2 3.4.3 Ceramics A. Material Description B. Method of Manufacture (i.e., isostatic, extruded, etc.) Raw Material (When required by CPI Purchasing Specification) A. CPI Material Purchasing Specifications (i.e., P3-1B, P1-7D, etc.) B. Size and/or Shape of Material C. Test Reports (chemical and physical) 3.4.4 3.4.5 Special Processing (Typical processing certifications include plating, priming, heattreating, ceramic metallizing, brazing, welding, etc.) A. Total Quantity Processed B. Definition of Process (CPI specification, MIL specification, or other brief description) Specific Requirements or Tests (Mechanical, Electrical, Environmental) Description of the specific item being certified 4.0 A. CPI Drawing and Note Number B. Applicable Specification and Requirement PACKAGING AND LABELING 4.1 Parts Protection in Packing Parts shall be packaged for shipment so they are protected from damage and contamination, prevented from nesting and entangling, and easy to unpack. Step 4.1.2B lists several packaging schemes that can be used as an aid. For more detail on packaging items, see Section 1 of M7-35, “Inventory packaging.” Spec. No.: M7-13 FABRICATION STANDARDS ECO: MPP615849 Rev. AV Date: May 16, 2016 MANUFACTURING SPECIFICATION 4.1.1 Page 6 of 21 Unacceptable Packing Materials Dusty and linty materials such as sawdust, shredded newspaper, and excelsior 4.1.2 Suitable Packing Materials A. Cellulose wadding (Kimpack), corrugated paper board, and expanded plastics (specific notes on drawings concerning packing requirements take precedence.) B. Table 1 lists the recommended packaging schemes for several commodities: TABLE 1. Packaging by Commodity Commodity Recommended Packaging Ceramics Individually package; bubble wrap Braze Wafers/Washers Poly bag; then lay flat in container (see P18-2 for packaging clean parts) Bellows Individually package; divider trays; Rondo boards Small Drift Tubes and TWT Cavity tray VMC-35, purchased from Anodes Odyssey (408) 260-4012 Individually wrap; poly bag Large Drift Tubes (MPP) Use plastic end caps to protect the nose Diaphragms Divider trays; individually wrap; poly bag (one piece per bag) Individually wrap in bubble wrap, end CONFLAT® Flanges cap on knife-edge side Coupled-Cavity Pole Pieces and Divider trays P99056, F19951, F19952; Cavity Plates poly bag (one piece per bag) Polished Parts (parts having an Individually wrap in lint-free paper, then exposed surface with a 16 finish or place in a bubble bag better) 4.1.3 Clean Parts Packaging Refer to CPI specification P18-2, “Clean Packaging of Supplier-Provided Parts,” for clean parts packaging requirements. 4.1.4 Properly Packed Materials Pack large shipments and heavy parts in small lots for easier handling. Shipments packaged in a single corrugated carton shall not exceed 40 pounds. 4.2 Transportation Corporate Freight Rates Suppliers are encouraged to take advantage of CPI’s corporate freight rates. Consult Purchasing for current carrier names and account numbers. Spec. No.: M7-13 FABRICATION STANDARDS ECO: MPP615849 Rev. AV Date: May 16, 2016 MANUFACTURING SPECIFICATION 4.3 Page 7 of 21 Package Labeling 4.3.1 Label Requirements Label each package as follows: 4.3.2 A. Name of Supplier B. CPI Division Purchase Order Number C. Receiving Area D. CPI Division Part Number and Revision Letter E. Quantity (use same unit of measure as stated on purchase order) F. Other applicable information (i.e., Just-in-Time Delivery labels, EPA requirements, clean parts labels, etc.) Multiple Container Lots Lots shipped in more than one container must be sequentially labeled (i.e., Box 1 of 3, Box 2 of 3, etc.) 4.3.3 Consolidated Shipments A consolidated shipment of multiple items and purchase orders is acceptable, provided that the shipping container is clearly marked as a consolidated shipment (see example below). Packing lists for individual purchase orders should be placed inside the consolidated shipping container. Sample marking: CONSOLIDATED SHIPMENT See packing lists in container for individual purchase orders. 4.3.4 Additional Labeling Requirements Labels shall meet all Federal and State labeling requirements, including those established by the EPA in 40 CFR, Part 82, “Protection of Stratospheric Ozone.” 5.0 GEOMETRIC DIMENSIONING AND TOLERANCING SYSTEM Interpret dimensions and tolerances according to the latest revision of ANSI Y14.5, “Dimensions and Tolerancing.” 5.1 Unspecified Tolerance When the tolerance limit is not specified on the drawing or sketch, the following shall apply: Decimal: Fraction: Angles: 1 place ±0.1 2 places ±0.02 3 places ±0.005 4 places ±0.0005 ±1/64 ±1° Spec. No.: M7-13 FABRICATION STANDARDS ECO: MPP615849 Rev. AV Date: May 16, 2016 MANUFACTURING SPECIFICATION 5.2 Page 8 of 21 Unspecified Finish The finish requirement for machined surfaces shall be 125 unless otherwise specified. Flaws are not included in surface finish measurements. The following flaws are not acceptable unless otherwise specified: Splits, tears, and cracks Displaced metal, folds (ironed-in or smeared-over scratches and burrs) Inclusions (imbedded particles—chips, burrs, foreign matter) Oxide (rust or corrosion) Seams The surface finish must not exceed the average value of microinches shown by the symbol ( ). Unless otherwise specified, the general finish in the title block applies only to machined surfaces. Commercial stock surface finish is acceptable when “stock” is specified as a dimension. 5.3 Unspecified Flatness When flatness is not specified, it shall not exceed the values in Table 2 and shall not violate the MMC perfect-form boundary. TABLE 2: Flatness Tolerance Surface Finish Required 63 Unit Variation in any Direction 0.003 in. per in. or better 64 or rougher 5.4 0.005 in. per in. Total Variation if Length is 1″ or More 0.003 times the longest element of the feature with a maximum of 0.012 0.005 times the longest element of the feature with a maximum of 0.020 Unspecified Cylindricity When cylindricity is not specified on the drawing, diameters shall be cylindrical within onehalf the feature size tolerance and shall not violate the MMC perfect-form boundary. 5.5 Unspecified Perpendicularity When implied right (90) angles are not specified in the drawing, they shall be within ±0 15’ of the intended 90 angle or 0.004 inch per inch maximum error and shall not violate the MMC perfect-form boundary. Spec. No.: M7-13 FABRICATION STANDARDS ECO: MPP615849 Rev. AV Date: May 16, 2016 MANUFACTURING SPECIFICATION 5.6 Page 9 of 21 Unspecified Parallelism When surfaces shown in parallel relationship are not specified on the drawing, they shall be parallel within 0.002 inch per inch of width or length and shall not violate the MMC perfectform boundary. 5.7 Unspecified Concentricity When concentricity is not specified on the drawing, the concentricity of any two round features shown on the same centerline shall be equal to one-half the arithmetic sum of the feature size tolerances. The feature having the smallest total tolerance shall be considered datum if no datum is specified. Example: The concentricity between D1 and D2 will be: Tolerance D1 = ±0.002 = 0.004 THIS IS DATUM (smallest total tolerance) D2 = ±0.005 = 0.010 Axis of D2 must be concentric to axis of D1 by 0.007 or less. [(0.004 + 0.010)/2 = 0.014/2 = 0.007] FIGURE 1: Unspecified Concentricity 5.8 Unspecified Position When positional symmetry is not specified, ( formerly ) features shown as lying on the centerline of a part (i.e., a slot in a screw head) shall be symmetrical within the total width tolerance of the feature. 5.9 Unspecified Circularity Diameters that do not have a specified roundness tolerance shall be round within one-half the feature size tolerance but must not extend beyond the MMC perfect-form boundary. 5.10 Unspecified Countersinks Unless otherwise specified, all countersinks shall be 82 ±5. Spec. No.: M7-13 FABRICATION STANDARDS ECO: MPP615849 Rev. AV Date: May 16, 2016 MANUFACTURING SPECIFICATION 6.0 Page 10 of 21 TOOLING Parts contamination can result from contact with some materials commonly used for tooling. Tooling made of brass, bronze, or platinum shall not be used. Cadmium- or zinc-plated tooling shall not be used. Exception: Parts that are not used inside the vacuum envelope of microwave, power-grid, and X-ray VEDs (or similar devices) are exempt from this requirement. These parts are either made from brass, aluminum, zinc, lead, and plastic or designated by the drawing as not used in the vacuum envelope of the VED. 7.0 CLEANING, PLATING, AND COATING OF SURFACES All fabricated parts must be received at CPI free of machining lubricants, oils, contaminants, and particles. (The exception to this rule shall be components made from materials that would rust if not protected by an approved rust inhibitor. Materials in this category shall be degreased and coated with an approved rust inhibitor before being packaged for shipment or introduced into the Supplier's stock). Plating, coating, or other metal finishing to be performed by Suppliers shall be specified on the drawing using military or industry standards. All quality-assurance provisions in the standard shall apply. Processes to be performed within CPI shall refer to the CPI specification. When a part or assembly drawing specifies plating or coating, dimensions on the drawing are the machined/fabricated dimensions. The part or assembly has been designed to allow for the application of the plating or coating as specified. Any dimensions that apply after plating will be noted separately. Specified coating thicknesses are the average thickness for the entire part. Normal thickness distribution based on current density is assumed. For example, areas of high-current density, such as sharp edges and outer ends of parts, can have considerably more than the specified coating thickness. Areas of critical thickness will be noted on the drawing. Compliance to critical thickness specifications must be verified and documented. All threaded holes shall be masked prior to plating or painting to ensure there is no buildup of the plating or paint in the threaded hole. 8.0 BURRS Burrs adversely affect VED performance by acting as traps for chemical cleaning solutions, serving as “virtual” leaks and as point emission sources in areas of high-electrical potential. 8.1 Definition A burr is found at the edge of a stamped or machined feature and is defined as a small projection of material that interrupts the normal contour of the plane or surface. (Note that this definition says a burr can only occur at an edge of a feature; anything on the surface is a nodule or particle, etc.) Spec. No.: M7-13 FABRICATION STANDARDS ECO: MPP615849 Rev. AV Date: May 16, 2016 MANUFACTURING SPECIFICATION 8.2 Page 11 of 21 Types Various types of burrs are defined as follows: An imbedded burr is any burr that has been pressed into the material. A feather burr is a very fine or thin burr generally less than 0.001-inch thick. A hanging burr is a burr that is not firmly attached to the workpiece. A rolled-over burr is a tight burr that is curled over on itself in such a manner that it traps contaminants within itself. NOTE: 8.3 ROLLED-OVER AND IMBEDDED BURRS ARE NOT ALLOWED. EMBEDDED PARTICLES ARE NOT ALLOWED. Height Hanging burrs and feather burrs are subject to the limits prescribed below. Burr height is defined as the maximum distance the burr projects above the surface of the workpiece. TABLE 3. Burr Heights Maximum Burr Heights Allowed for Machined Features 32 Finish or Better 0.0005 63 Finish 0.002 125 Finish or Worse 0.003 In addition to burr height, burr direction may be a critical factor for sheet-metal parts. If so, the burr direction will be called out on the drawing (see Section 10.12). Maximum burr heights for sheet-metal parts will be found in Section 10.11. 8.4 Removal It shall be standard practice to remove burrs from the edges of all surfaces, even if this requirement is not noted on the drawing, such that the requirements stated in Section 8.2 and Section 8.3 are satisfied. The notation “No Burrs” appearing on a drawing specifies that burrs be removed to the extent that they are not visible under 10X magnification. While deburring, it is imperative that excessive material is not removed; after deburring, the parts must still be within the dimensional tolerances specified on the print. The deburring method used must not introduce any contamination, and all loose particles must be removed. Contamination resulting from embedded particles introduced during the deburring processes can adversely affect the performance of our product. The use of bonded abrasives (i.e., a Cratex stick) that can leave embedded particles is NOT acceptable. Spec. No.: M7-13 FABRICATION STANDARDS ECO: MPP615849 Rev. AV Date: May 16, 2016 MANUFACTURING SPECIFICATION 8.5 Page 12 of 21 Edges An edge is defined as the intersection of two planes of base material at an angle greater than 180 (outside). 180¡ 180 EDGE D4019 FIGURE 2: Edges It shall be standard practice to remove all sharp edges unless otherwise specified. Edges shall be broken by either a 45 chamfer or a radius. If limits are not specified on the drawing, a 0.005-inch maximum chamfer or radius is acceptable for lengths less than 1 inch. For features greater than 1 inch, a 0.010-inch maximum chamfer or radius is acceptable. A “sharp edge” callout on a drawing shall be interpreted as being limited to a 0.002-inch maximum chamfer or radius. 8.6 Corners A corner shall be defined as the intersection of two or more planes of base material at an angle less than 180 (inside). CORNER 180¡ D4020 FIGURE 3: Corners Unless otherwise specified on the drawing, all corners shall be limited to a 0.010-inch maximum radius. A “sharp corner” callout on a drawing shall be interpreted as being a corner with no greater than a 0.002-inch maximum radius. Undercuts shall be subject to rejection unless otherwise specified on the drawing. Spec. No.: M7-13 FABRICATION STANDARDS ECO: MPP615849 Rev. AV Date: May 16, 2016 MANUFACTURING SPECIFICATION 8.7 Page 13 of 21 Sheet Metal For additional requirements concerning burrs on sheet-metal products, see Section 10.11. 9.0 THREADS All threads, unless otherwise specified on the drawing, shall conform to the unified tabulations and formulations of FED-STD-H28, “Screw Thread Standards for Federal Services.” Unified form threads, American National Form threads, special threads, and unified miniature screw threads shall be defined by the unified system. 9.1 Internal Threads All internal threads shall be tapped using standard machine screw taps or machined. THREAD-FORMING TOOLS ARE PROHIBITED UNLESS OTHERWISE SPECIFIED as formed threads can trap contaminants. EXCEPTION: Parts that are not used inside the vacuum envelope of vacuum-electron devices are exempt from this requirement. These parts are either made from brass, aluminum, zinc, lead, or plastic or are designated by the drawing as not used in the vacuum envelope of the VED. 9.2 Threaded Holes All threaded holes shall be countersunk 82 ± 5 to a diameter equal to at least the major diameter of the specified thread. In the case of through-holes, this requirement shall apply to both ends. The countersink diameter shall not exceed 0.020 inch over the major thread diameter. The specified depth of a threaded hole shall mean there shall be full threads to that depth. Where a three-place decimal dimension (± 0.005 tolerance) is used to define thread depth, one full thread shall be allowed beyond the dimension. The depth of the tap drill shall not be specified unless critical. If the depth of a tap/twist drill hole is not specified, the depth of the hole shall not exceed the full thread depth plus a dimensional allowance equal to the nominal thread diameter. FULL THREAD DEPTH MAX. DEPTH OF HOLE= FULL THREAD DEPTH PLUS THREAD DIA. FIGURE 4: Thread Depth In gauging a threaded hole, the “No-Go” gauge shall not penetrate more than three turns. Exceptionally short thread length (less than three pitches) may pass over the plug gauge provided there is a perceptible drag. The “Go” gauge shall freely penetrate the full length of the thread. Spec. No.: M7-13 FABRICATION STANDARDS ECO: MPP615849 Rev. AV Date: May 16, 2016 MANUFACTURING SPECIFICATION 9.3 Page 14 of 21 Threaded Parts The end of all external threads shall be chamfered at 45 ± 5 to the minor diameter. 9.4 Full-Form Threads The length of fully formed threads is dimensioned. When only one dimension is used to specify the length of threads, it is interpreted to mean the length of fully formed threads, excluding runout. Where a chamfer, not exceeding two pitches in length, exists at the entering end of the thread, it is included in the length of fully formed threads. Figure 5 below shows methods of delineating with no limit on runout. X.XXX X.XXX THREAD LENGTH D4025 FIGURE 5: Thread Length 9.5 Unspecified Thread Class of Fit TABLE 4: Thread Class Thread Description External Threads Internal Threads External Threads (Metric) Internal Threads (Metric) Threaded Inserts (#3–#8) Threaded Inserts (>#8) 10.0 Thread Class of Fit 2A 2B 6G 6H 2B 2B or 3B SHEET-METAL PRODUCTS FABRICATION REQUIREMENTS 10.1 Sheet Metal Sheet metal is considered to be sheet stock that has a nominal thickness of 0.250 (1/4) inch or less. 10.2 Features and Surfaces Features and surfaces of sheet-metal parts shall be within drawing dimensional limits of size in the unrestrained condition unless otherwise specified. Spec. No.: M7-13 FABRICATION STANDARDS ECO: MPP615849 Rev. AV Date: May 16, 2016 MANUFACTURING SPECIFICATION 10.3 Page 15 of 21 Machined Features Obvious machined features such as countersinks, chamfers, screw threads, and closetolerance (0.003 inch or less) holes shall conform to the body of this standard. 10.4 Circular Runout The circular runout of any internal or external diameter shall not exceed the value specified in Table 5 with respect to any other diameter on the same axis. If a datum axis is established by the drawing, the circular runout shall be in relation to that datum axis. TABLE 5: Circular Runout of Diameters DIAMETER (Inches) Through 6.000 6.001 through 9.000 9.001 through 20.000 20.001 through 36.000 Over 36.000 10.5 CIRCULAR RUNOUT TOLERANCE (Inches) 0.040 0.070 0.100 0.150 0.200 Washer-Type Punching The center hole of washer-type punchings shall be located within the position tolerance shown in Table 6 in relation to the outside diameter. TABLE 6: True Position of Washer-Type Punchings Relative to OD as Datum Feature INSIDE DIAMETER (Inches) Through 6.000 6.001 through 12.000 12.001 through 24.000 Over 24.000 10.6 POSITION TOLERANCE (MMC) (Inches) 0.030 dia. 0.060 dia. 0.100 dia. 0.150 dia. Flatness Variations in surface flatness shall not exceed the values shown in Table 7 and Table 8 and shall not violate the dimensional limits of size. TABLE 7: Flatness for Nonwelded Surfaces NOMINAL STOCK THICKNESS (Inches) Through 0.090 0.091 through 0.250 UNIT VARIATION IN ANY DIRECTION 0.010 in/in 0.007 in/in Spec. No.: M7-13 FABRICATION STANDARDS ECO: MPP615849 Rev. AV Date: May 16, 2016 MANUFACTURING SPECIFICATION Page 16 of 21 TABLE 8: Flatness for Welded/Brazed Surfaces NOMINAL STOCK THICKNESS (Inches) Through 0.032 0.033 through 0.060 0.061 through 0.125 0.126 through 0.250 10.7 UNIT VARIATION IN ANY DIRECTION 0.025 in/in 0.020 in/in 0.015 in/in 0.005 in/in Parallelism and Perpendicularity The elements of flat sheet-metal surfaces that are shown as parallel or perpendicular shall be parallel or perpendicular to each other within 3. The datum shall be the longest adjacent surface that is parallel or perpendicular to the surface being measured. 10.8 Edges and Corners Sheared edges are permissible but they, and all other edges and corners, shall be broken in accordance with the illustration below. This applies only to finished parts and not to “inprocess” pieces of a welded or brazed assembly. 0.015 0.005 RAD. EXTERNAL EDGES AND CORNERS SHALL FALL ENTIRELY WITHIN THE CROSSHATCHED AREA. NO BURRS PERMITTED. 0.015 FIGURE 6: Edges and Corners 10.9 Stock Thickness after Forming Sheet-metal thickness in areas affected by forming may be reduced by a maximum of 25 percent of the maximum stock thickness. Local thickening due to the part shape and the forming process is acceptable up to 30 percent of the maximum stock thickness. If material thickness is 0.025” or less, supplier must verify thickness and pay particular attention to the formed feature(s). Verification methods can include mechanical measurement, CMM, cross-section (i.e., EDM cut, metallurgical section, milling), or ultrasonic. Spec. No.: M7-13 FABRICATION STANDARDS ECO: MPP615849 Rev. AV Date: May 16, 2016 MANUFACTURING SPECIFICATION Page 17 of 21 10.10 Breakaway The maximum breakaway of punched or sheared edges shall not be more than 20 percent of the stock thickness as shown below. The dimensional limits of size apply only to those portions of the edge where breakaway has not occurred. FIGURE 7: Maximum Breakaway 10.11 Burrs The following burr specifications are in addition to those covered in Section 8: Limitations — under the conditions specified below, maximum burr heights are as follows (also see illustration in Section 10.12): TABLE 9: Burr Height Allowance STOCK THICKNESS 0.004 and under over 0.004 to 0.014 incl. over 0.014 to 0.039 incl. over 0.039 to 0.124 incl. over 0.124 to 0.186 incl. over 0.186 to 0.311 incl. over 0.311 MAX BURR HEIGHT ALLOWANCE 0.001 0.0015 0.002 0.003 0.004 0.005 0.010 Wire and ribbon burrs on cut lengths of wire and ribbon, including flattening because of shearing pressure, shall not exceed 10 percent of the diameter or thickness unless otherwise specified. Spec. No.: M7-13 FABRICATION STANDARDS ECO: MPP615849 Rev. AV Date: May 16, 2016 MANUFACTURING SPECIFICATION Page 18 of 21 10.12 Burr Symbols and Drawing Callouts A “B” symbol placed on extension lines indicates that burrs are acceptable. The maximum burr height allowed is shown adjacent to the symbol. Arrowheads may be used to indicate the side on which burrs may occur. Symbols placed on both sides indicate that burrs are acceptable on both sides. A radius may be specified on an edge to show the direction of punching. FIGURE 8: Burr Symbols 11.0 CASTING AND FORGING REQUIREMENTS 11.1 Position The position of coaxial or coplanar cast or forged features shall be in accordance with Table 10 with respect to each other; it should be noted that the position does not include out-ofroundness. If a cast or forged datum axis is established by the drawing, the position control shall be in relation to that datum axis. The concentricity shall be ±0.010″ at the lowest point on the surface of the forging before any surface-removal procedure (OFE Copper only). TABLE 10: Position of Coaxial/Coplanar Features Sand Casting Die Castings Shell, Plaster, Ceramic, Permanent Mold, or Investment Castings Forgings Feature Dia/Width Position Tol. RFS (S) Up to 6.000 6.001 to 12.000 Over 12.000 Up to 6.000 6.001 to 12.000 Over 12.000 Up to 6.000 6.001 to 12.000 Over 12.000 Up to 6.000 6.001 to 12.000 Over 12.000 0.060 0.090 0.120 0.020 0.040 0.060 0.040 0.060 0.080 0.060 0.090 0.120 Spec. No.: M7-13 FABRICATION STANDARDS ECO: MPP615849 Rev. AV Date: May 16, 2016 MANUFACTURING SPECIFICATION 11.2 Page 19 of 21 Flatness Surface flatness shall not exceed the values specified in Table 11 except in the area of a parting line. TABLE 11: Flatness FLATNESS TOLERANCE Variation In Total Variation Any Direction (Lengths of More Than 1 Inch) Surface Finish 250 and Finer 0.015 in./in. 0.060 max 251 Through 500 0.020 in./in. 0.080 max 500 and Finer 0.010 in./in. 0.060 max 500 and Over 0.020 in./in. 0.100 max Castings Forgings 11.3 Cleanup Gates, risers, flash, runners, and parting lines on surfaces not subject to subsequent machining shall be trimmed and blended smooth with the part contour. Surfaces subject to subsequent machining shall be finished according to normal industry practice. 11.4 Mismatch Parting-line mismatch for forgings shall not exceed 0.05 inch maximum. Mismatch is defined as a defect resulting from die misalignment, producing an offset on the surfaces of the forging at the parting line. The mismatch of castings shall be contained within the applicable position requirements. 11.5 Draft Draft shall be applied as additional material to the dimensions shown on the drawing and shall not exceed the limits specified in Table 12. TABLE 12: Draft Angle DRAFT ANGLE Internal External Sand, Shell Mold, and Ceramic Mold Castings Plaster Mold Castings Investment Castings Permanent Mold and Semiperm Mold Castings Forgings 3 max 3 max 130’ max 4 max 10 max 3 max 130’ max 130’ max 4 max 8 max Spec. No.: M7-13 FABRICATION STANDARDS ECO: MPP615849 Rev. AV Date: May 16, 2016 MANUFACTURING SPECIFICATION 11.6 Page 20 of 21 Repair Castings and forgings shall not be repaired by welding, plugging, impregnating, peening, or any other methods except as permitted by specific drawing notes. Castings that shall be subsequently welded or brazed shall not be impregnated. Surface conditioning using standard shop practice for removal of surface defects is permissible within drawing dimensional limits. 12.0 EDM FABRICATION REQUIREMENTS For components fabricated using an EDM process (including wire EDM), parts will be delivered free of any contaminants from the dielectric fluid and electrode material. If transfer of material from the electrode is unavoidable, the supplier is responsible for subsequent cleaning to remove the deposit or for using a non-contaminating electrode such as tungsten. Spec. No.: M7-13 FABRICATION STANDARDS ECO: MPP615849 Rev. AV Date: May 16, 2016 MANUFACTURING SPECIFICATION Page 21 of 21 APPENDIX: GEOMETRIC SYMBOLOGY SYMBOL MEANS Datum Symbol Datum Target () ANSI REFERENCE 3.3.2 3.3.3 Basic Dimension 3.3.4 Diameter 3.3.7 Spherical Diameter Reference Feature Control Frame --3.3.8 3.4.2.1 Least Material Condition (LMC) Regardless of Feature Size (RFS) Maximum Material Condition (MMC) 3.3.5 3.3.5 3.3.5 Projected Tolerance Zone 3.3.6 Radius Spherical Radius Arc Length Chain Line Flatness Flatness on Older Prints Straightness Circularity (Roundness) 3.3.7 1.8.2.5 3.3.9 --6.4.2 --6.4.1 6.4.3 Cylindricity Perpendicularity 6.4.4 6.6.4 Angularity 6.6.2 Parallelism Profile of a Line Profile of a Surface Circular Runout Total Runout Concentricity/Coaxiality Position 6.6.3 6.5.2 (b) 6.5.2 (a) 6.7.2.1 6.7.2.2 5.11.3 5.2 Symmetry (Use of Preferred Position) Counterbore or Spotface Countersink Depth --3.3.10 3.3.11 3.3.12 Repetitive Features and Dimensions ---