2950012333468_Trbchrgr_R.pdf

MAL_1221

WORK ITEM 1: 2950-01-233-3468, Turbocharger, Repair

1. SCOPE

1.1 Intent. This specification covers the requirements for the receipt, disassembly, inspection, condition/test reports, overhaul, reassembly, testing, preservation, packing and marking of Alco

Turbochargers used on U.S. Coast Guard 251 Series Alco Diesel Engines.

1.2 Government-furnished property.

MTI ITEM DESCRIPTION NSN

P/N

QTY

(EA.)

APPLICATION

Y ***Turbocharger, Model 131

NSN: 2950-01-233-3468

PN: 22602171-3

1 WMEC 210A

*Government-loaned property, which shall be returned to the Coast Guard upon completion of the contract.

**New or refurbished equipment that the Government may provide for installation in place of existing equipment.

***Government-furnished property, which is to be supplied by the Coast Guard.

2. REFERENCES

COAST GUARD DRAWINGS

None

COAST GUARD PUBLICATIONS

None

OTHER REFERENCES

Alco Maintenance Manual MI-11206C for Turbocharger Model 131 Dated July 1981

ASQ/ANSI/ISO 9001, Dated 20 Nov 2015, Quality Management Systems - Requirements

ASTM D7478/D7478MD6251M, Dated 1 Nov 2011 (R2017), Standard Specification for Heavy

Duty Sheathed Wood Crates

ISO/IEC 16388-2007, May 15 2007 Information technology — Automatic identification and data capture techniques — Code 39 bar code symbology specification

ISO/IEC 17025:2017, Dated 2017, General Requirements for the Competence of Testing and

Calibration Laboratories

MIL-PRF-21260E Dated July 31, 1998 Lubricating Oil, Internal Combustion Engine, Preservative Break-In

MIL-PRF-16173E w/ Int. Amendment 1, Sep 2006, Corrosion Preventive Compound, Solvent

Cutback, Cold- Application

MIL-STD-129R, 27 Sep 2019 Military Marking for Shipment and Storage

MIL-STD-2073-1E Change 4, 22 Apr 2019 Standard Practice for Military Packaging

NAVSEA T9074-AS-GIB-010/271, Dated February 16, 1999, Requirements for Nondestructive

Testing Methods.

NAVSEA TT-P-28H, Dated 1 Jul 2021, Coating, Heat Resisting

SAE AMS-STD-595A, Dated Feb 2017, Colors Used in Government Procurement

SSPC-PAINT 25, Dated May 1, 1997, Editorial Changes November 1, 2004, Zinc Oxide, Alkyd, Linseed Oil Primer for Use Over Hand Cleaned Steel (Without Lead and Chromate

Pigments-Red Iron Oxide)

2.1 Document availability. The documents listed in this section are referenced in sections 3, 4 and 5 of this work item and drawings stated in this Work Item. To obtain the referenced documents see section

6.1.

2.2 Specification order of precedence. The Applicable Documents described are required to be adhered to in fulfilling the contract. In the event of a conflict between the text of this specification and the references cited herein, this work item shall take precedence. Nothing in this document, however, supersedes applicable laws and regulations unless a specific exemption has been obtained.

3. REQUIREMENTS

3.1 General. Inspections, repair/overhaul and testing of each turbocharger shall be accomplished in accordance with all applicable documents listed in section 2.0 of this specification.

3.1.1 Tech rep.

None.

3.2 Government furnished property (GFP). The Contractor shall provide protective storage for the GFP when not in use, and safe handling when in use.

3.2.1 The storage area shall at a minimum be closed on all sides, dry, and locked when the equipment is not in use.

3.3 Arrival inspection/disassembly inspection. Each turbocharger received by the Contractor shall be disassembled and inspected. A detailed report shall be completed and submitted to the Contracting

Officer to include the following information:

• Date of inspection

• Inspectors name

• Identification of units by serial number, part number, and stock number

• Condition of the shipping crate and any cost of repair

• List Mandatory parts as priced in the contract as one line and a total price (Appendix A)

• List of contingency parts by part number & CLIN, and their applicable prices (Appendix B)

• Cost of overhaul labor as applicable

• Comments if any pertaining to unusual observations during inspection & disassembly

• Dimensional inspection of bearing bores, rotor shaft journal areas, seal areas, disc fit and impeller fit areas using clearance table in Appendix C and D as applicable.

• A list of defective or worn parts recommended for repair/refurbishment vice replacement and the associated cost to accomplish

• If not previously condemned, each rotor disk, impeller, inducer, and gas inlet of each turbocharger shall be dye penetrant tested in accordance with NAVSEA T9074-AS-GIB-

010/271 and the results provided in the initial report with discrepancies highlighted

3.3.1 No further work shall be accomplished until the report is approved by the Contracting Officer.

3.4 Overhauls. Each turbocharger shall be overhauled in accordance with the documents cited in section

2.0 and appendices A through C as applicable.

3.4.1 Replacement parts. All replacement parts shall be new and manufactured in accordance with Alco specifications and standards, the Original Equipment Manufacturer (OEM).

3.4.1.1 Defective or worn parts may be repaired/refurbished if the Contractor deems it more economical than replacement. The performance and function of the repaired parts shall be equal to that of a new part.

A listing of all parts recommended for repair shall be part of the Arrival Inspection as required in section

3.3 of this specification.

3.4.2 Mandatory repairs. The following shall be accomplished on each turbocharger inducted for repair/overhaul:

• Cleaning/repairing of all bolt holes

• Rotor Balancing

• Installation of Mandatory Replacement Parts

• Cleaning and Painting (see section 3.6)

3.5 Mandatory replacement parts. The following parts are mandatory to replace.

• Model 131 as per Appendix A

3.6 Surface cleaning & painting.

3.6.1 Cleaning.

• All scale and paint shall be removed

• All surfaces shall be solvent cleaned of all grease and oil

3.6.2 Painting.

3.6.2.1 These items shall be masked or plugged and not painted:

• Oil inlet and drain openings

• Hoses, hose connections or openings

• Identification plate

• Air inlet and discharge openings and flanges, exhaust inlet and discharge openings and flanges

• Water inlet and discharge openings

• Any other openings that will permit foreign material to enter the turbocharger

3.6.2.2 All external areas not exposed to temperature that normally exceeds 300 degrees F., while turbocharger is in operation, shall be coated as follows:

• One coat, 2-3 mils thickness with Primer in accordance with SSPC-PAINT 25

• Two coats, at least 2 mils thick total, of high gloss Equipment Enamel, MIL-E-15090C, Formula 111, Type I, Class 1, light gray, Color No. 16492 per SAE-AMS Standard 595

3.6.2.3 All external surfaces normally exposed to temperatures that exceeds 300 degree F. shall be painted with 2 coats, 2 mils total thickness of Heat-Resistant Aluminum Paint, NAVSEA Specification TT-P-

28H.

3.6.2.4 When all paint is dry, the masking shall be removed.

3.7 Reassembly report/test report. The Contractor shall submit a Reassembly Report/Test Report to the

Contracting Officer for approval.

3.7.1 The Reassembly Report/Test Report shall include all inspections and tests specified herein and all other inspections and tests needed to verify conformance to the requirements.

3.7.2 The Reassembly Report/Test Report shall include (unless otherwise noted), but not be limited to:

• Time and date of test or inspection

• A chronological listing of the tests and inspections performed

• Step-by-step inspection procedures for the assembly and pass/fail criteria

• Assembly dimensions, tolerances, thrust, adjustments, torque specs, and balance records observed, and all deficiencies found and the corrective action taken. Any deficiencies noted shall be highlighted

• A complete listing of all measuring test equipment (MTE) used with MTE serial numbers

• Dimensional inspection report with tolerances. Any deficiencies noted shall be highlighted

• Rotor assembly balance record, with tolerances o The rotor assemblies shall be spun-balanced at the OEM recommended RPM.

o The rate of unbalance for each model of Turbocharger shall not exceed the following

Specified amounts.

▪ Model 131 - 0.02 in. oz.

• Date and signatures of test or inspection personnel

• Signature of Government witness, if any

3.8 Notifications & inspections. The Contractor shall notify the Contracting Officer a minimum of ten

(10) calendar days prior to any inspections or testing required herein.

4. QUALITY ASSURANCE

4.1 Responsibility for inspection. The Contractor shall be responsible for the performance of all inspection requirements specified herein. The Contractor shall provide space, personnel and test equipment for the conduct of all inspection requirements. All inspection and testing shall be performed at the Contractor's plant or at other facilities acceptable to the Coast Guard. The Coast Guard reserves the right to verify or have performed any of the inspections set forth in this specification where such inspections are deemed necessary to assure that supplies and services conform to the prescribed requirements.

4.2 Responsibility for compliance. All items shall meet the requirements of sections 3 and 5. The inspections set forth in this specification shall become part of the contractor's overall inspection system or quality program. The absence of any inspection requirements in this specification shall not relieve the contractor of the responsibility of assuring that all products or services submitted to the government for acceptance comply with all requirements of the contract. Sampling for quality conformance does not authorize submission of known defective material (either indicated or actual) nor does it commit the government to acceptance of defective material.

4.3 Quality system. The contractor shall maintain a documented Quality System in accordance with

ASQ/ANSI/ISO 9001. A copy of this program shall be submitted to the Contracting Officer for approval within 15 calendar days after contract award.

4.4 Inspections. The inspections required herein are the minimum required and are not intended to replace any controls, examinations, inspections or tests normally employed by the Contractor to assure the quality of the equipment. The following are required and will be monitored by a Government Quality Assurance

Representative.

4.4.1 Rotor balancing inspection in accordance with section 3.7.2.g of this specification

4.4.2 Preservation, packing, and marking in accordance with section 5.0 of this specification.

4.5 Calibration system. The Contractor shall maintain a test equipment calibration program conforming to

ISO/IEC 17025:2017. The Contractor shall have a copy of the calibration program readily available during the term of this contract for review by any Coast Guard personnel upon request.

4.5.1 Calibration system records. The calibration system records shall be maintained for inspection for the duration of any contract referencing this specification.

4.6 Noncompliance. Shall mean any single failure of any individual part or subsystem during inspection or testing.

4.6.1 The Contractor shall replace the failed part with new, and continue testing.

4.6.2 If, during assembly any noises, rubbing, or grinding are heard or felt indicating potential problems the entire test procedure shall be repeated after replacement of the failed part(s).

4.6.3 Any flaws detected in materials or construction methods which reduces the usefulness of the turbochargers to the Coast Guard shall be resolved before completing any further work.

4.6.4 Any unusual noises or other non-compliances, as determined by the Coast Guard Inspector, will require re-testing and shall be cause for failure.

4.7 Test and inspection reports. One copy of any inspection or test report approved for use from submittal shall be sent to the Contracting Officer for approval. A copy shall also be given to the Coast Guard

Quality Assurance Representative upon his arrival at the Contractor's facility.

4.8 Records. The Contractor shall maintain records by serial number of all inspections and tests.

4.8.1 The records shall indicate the nature and number of observations made, the number and type of deficiencies found, and the corrective action taken.

4.8.2 Copies of all records shall be maintained for Coast Guard inspection at any time during the duration of any Contract referencing this specification.

4.9 Discarded parts. All parts scrapped by the Contractor shall be saved until rendered scrap by a Coast

Guard representative.

4.10 Packing inspection. The Contractor shall notify the Contracting Officer a minimum of ten (10) calendar days prior to the scheduled preservation, packing, and marking of the completed units.

5. PRESERVATION, PACKING, MARKING, AND SHIPPING

5.1 General. Each Turbocharger shall be cleaned, preserved, packed, marked and bar-coded as specified herein. Preservation, packing, marking and bar-coding will be inspected by SFLC QA personnel at

Contractor’s facility.

5.2 Preservation. The Contractor shall preserve all Turbochargers in accordance with MIL-SPEC-2073-

1E, Method 20.

5.2.1 Internal.

5.2.1.1 Internal oil passages and bearings shall be spray/fogged and drained with Code 10, Grade 30 preservative as specified by MIL-STD-2073-1E APPENDIX J, TABLE J.III.

5.2.1.2 Internal water passages shall be spray/fogged and drained with Grade 3 preservative as specified by MIL-PRF-16173E(SH).

5.2.2 External. Unpainted surfaces shall be coated with Code 19, Grade 4, corrosion preventative as specified by MIL-STD-2073-1E APPENDIX J, TABLE J.III.

5.2.2.1 All fittings or openings that would allow foreign material to enter the unit shall be plugged or capped.

5.2.2.2 All pipe plugs must have the plugs removed. The hole and plug threads shall be cleaned with a tap and dye set. The pipe plug shall be replaced as a Contingency Item, if necessary. All pipe plugs shall be reinstalled and hand tightened. Red tag shall be applied to unit identifying plugs as being hand tight only.

5.2.2.2.1 VPI paper shall be placed between the flanges and the bolted on cap.

5.3 Packing. Each Turbocharger shall be individually packed in its own wooden box in accordance with accordance with ASTM D7478/D7478M, Class 2, Style A.

5.3.1 Top, side and end panels shall be fabricated and assembled (screwed vice nailed) to each other as specified for Type I, and the combination fastened (bolted) to skid as specified for Type II.

5.3.2 Each turbocharger shall be supplied with a gasket installation kit to facilitate installation using the correct gaskets and seals. This kit shall be made part of the package. The contents shall be in a plastic bag and placed in a cardboard and clearly marked “installation gasket kit”.

5.4 Marking. Shipping container shall be stenciled with the information laid out below. Markings shall be placed on each side of the two longest sides of the container so it will be visible to a forklift driver during storage and shipment. Stencil shall be applied directly on the container and a minimum of 1inch height black characters on a highly contrasting painted background, using permanent waterproof ink or enamel paint. Marking is in accordance with MIL-STD-129R.

5.4.1 All previous markings and labels shall be completely removed from the reusable shipping container prior to the applications of any new markings.

5.4.2 Marking layout (ready for issue) “A” condition Model 131 turbocharger.

NATIONAL STOCK NUMBER

2950-01-233-3468

ITEM NAME

TURBOCHARGER

MODEL NUMBER

PART NUMBER

22602171-3

SERIAL NUMBER

As per enclosed item

CONTRACT NUMBER (See Contract)

DELIVERY ORDER NUMBER

(See Contract)

SHIPPING DATE

"The Delivery Date to SFLC"

WARRANTY EXPIRATION

DATE

As Determined by Contractor

SHIPPING WEIGHT (LBS)

As Determined by Contractor

QUANTITY & UNIT OF ISSUE 1 - EA

CONDITION

CONDITION A

OTHER DATA AS DIRECTED

COAST GUARD SFLC MATERIAL

REUSABLE CONTAINER, DO NOT

DESTROY,

REMOVE BOLTS, LIFT CRATE FROM

SKID.

5.5 Bar coding. U.S. Coast Guard requires bar coding of the NSN, IAW ISO/IEC 16388-2007 Code 39

Symbology.

5.5.1 Bar coding label. Can be applied separately or as part of the marking required in 5.4.

5.6 Shipping. The Contractor shall ship, and deliver the repaired diesel engine turbocharger to the government address specified in paragraph. 5.6.1 Notice the Contracting Officer representative (COR) and KO about the shipment 7 days in advance. Provide timely shipping information to COR including the name of the shipping company, date of shipment leaving Contractor’s facility, and expecting arrival date and time at the government facility. No shipment shall arrive outside of government normal business hours as determined by the KO.

5.6.1 Unless otherwise specified, the Contractor shall ship, and deliver the diesel engine turbocharger(s) to the following government address:

U.S. Coast Guard

Surface Forces Logistics Center

2401 Hawkins Point Rd, Bldg. 88

Baltimore, MD 21226

NOTE

Normal deliver hours at the warehouse are Monday through Friday 0730-

1300. If delivery is needed to be made outside that delivery window the

Contractor shall notify the Contracting Officer.

6 NOTES

6.1 Document sources.

6.1.1 Government document sources.

• Department of Defense Single Stock Point (DODSSP)

Building 4, Section D

700 Robbins Avenue

Philadelphia, PA 19111-5094

215-697-2667/2179

FAX 215-697-1462

• DOD & Navy Publications & Forms (Other Than DODSSP)

Naval Publication and Forms Center

5801 Tabor Ave.

Philadelphia, PA 19120

215-697-2000

• ASSIST (Database for Military Specifications) https://assist.dla.mil/online/start/ http://quicksearch.dl.mil Assist Service Desk: PH: 215-737-8000

• USCG Surface Forces Logistics Center https://assist.dla.mil/online/start/ http://quicksearch.dl.mil/

2401 Hawkins Point Road

Baltimore, MD. 21226-5000

Phone: 410-762-6474

ATTN: Yvette Rene Johnson

6.1.2 Commercial document sources.

• American National Standards Institute (ANSI)

1899 L St. NW 11th Floor

Washington, DC 20036

Phone: 202-293-8020 www.astm.org

• American Society for Quality (ASQ)

600 North Plankinton Avenue

Milwaukee, WI 53203

Phone: 414-272-8575

Fax: 414-272-1734

• ASTM International

1850 M St. NW #1030

Washington, DC 20036

• International Standard Organization (ISO)

1, ch. De la Voie-Creuse

CP 56 - CH-1211 Geneva 20

Switzerland

Phone: +41 22 749 01 11

Fax: +41 22 733 34 306.1

• Society for Protective Coatings

Steel Structures Painting Council (SSPC)

800 Trumbull Drive

Pittsburgh, PA 15205

PH: 412-281-2331

http://www.astm.org/

APPENDIX A

MANDATORY REPLACEMENT PARTS - MODEL 131

Part Number Description Quantity

2151091501 (21510915-1) Gasket 1

21526718-1 O-Ring 1

21536512-1 Gasket 1

2154432-2 Gasket 2

2154433-2 Gasket 1

2154434-1 Gasket 2

2154435-1 Gasket 2

2260164-1 Bearing Assembly 1

2260165-1 Bearing Assembly 1

22610217 Shim 1

22610218 Shim 1

22610221-1 Shim 1

22612117 Oil Seal 1

22612118-2 Oil Seal 1

APPENDIX B

CONTINGENCY REPLACEMENT PARTS - MODEL 131

Part Number Description Quantity

16393723 Pipe Plug 1

21512863 Capscrew, Special 16

21512865 Capscrew 18

2151311-1 Lockwasher 2

2151312-1 Lockwasher 42

2151313-1 Lockwasher 43

21513510-1 Capscrew 12

21513513-1 Capscrew 4

2151352-1 Capscrew 2

2151495-1 Washer 4

2151697-1 Nut 21

21517744-1 Dowel 6

21529627 Flathead Screw 2

2153284 Plug 1

2153286 Plug 1

2154765 Dowel 2

21555893 Capscrew 42

22600431-1 Air Discharge Casing 1

22600452-1 Air Inlet Assembly 1

22600454 Gas Inlet Assembly 1

22600456-1 Rotor Assembly 1

22610525-1 Air Inlet Casing 1

22611513 Capscrew 6

2261260 (22612620) Gas Inlet Casing 1

22612622-1 Basic Assembly 1

22612715-1 Turbine Casing 1

22613016-1 Cover 1

22613017-1 Cover 1

2261309-1 Cover 1

2261462-1 Nozzle Clamp 1

2261553 Connector 1

2261611-1 Shroud Ring 1

22616526-1 Nozzle Ring 1

22616715 Diffuser Ring 1

2402085 Cover 2

2402086 Cover 2

2402087 Cover 1

21549661 Capscrew 6

APPENDIX C

TABLE OF CLEARANCES FOR MODEL 131

REFER TO ILLUSTRATION #1

Measurement Location Minimum Maximum

1) Nozzle Ring and Gas Inlet Casing (Outside) Dia. Cl. 0.075” 0.095”

2) Nozzle Ring and Gas Inlet Casing (Inside) Dia. Cl. 0.002” 0.008”

3) Turbine Disc and Oil Seal Dia. Cl. 0.016” 0.022”

4) Turbine End Oil Seal and Main Casing Dia. Cl. 0.0005” 0.0035”

5) Shaft and Bearing Carrier Long. Cl. 0.047” 0.078”

6) Shaft and Oil Seal Dia. Cl. 0.018” 0.023”

7) Bearing and Floating Bushing Long. Cl. 0.006” 0.020”

8) Shaft and Bearing Carrier; Shaft and Bearing Dia. Cl. 0.018” 0.021”

9) Bearing Carrier and Main Casing Dia. Cl. 0.0010” 0.0005”

10) Air Nozzle and Shaft Long. Cl. ¼” 3/16”

11) Turbine Disc and Oil Seal (Radial Clearance) Rad. Cl. 1/8”

12) Nozzle Ring and Clamp (Inner) Dia. Cl. 0.032” 0.044”

13) Nozzle ring and Clamp (Outer) Dia. Cl. 0.030” 0.050”

14) Nozzle Ring and Shroud Long. Cl. 0.015” 0.022”

15) Shroud Ring and Main Casing (Inside) Dia. Cl. 0.002” 0.006”

16) Shroud Ring and Main Casing (Outside) Rad. Cl. 0.084” 0.104”

17) Blower End Oil Seal and Main Casing Dia. Cl. 0.121” 0.133”

18) Impeller and Main Casing (Cold) Dia. Cl. 0.182” 0.190”

19) Impeller and Casing (Datum) Long. Cl. 0.005”

20) Diffuser and Air Discharge Casing Dia. Cl. 0.002” 0.010”

21) Air Discharge Casing and Impeller Dia. Cl. 0.030” 0.056”

22) Inducer and Air Discharge Casing Dia. Cl. 0.050” 0.060”

23) Bearing Carrier and Retainer Dia. Cl. 0.000” 0.002”

24) Floating Bushing and Bearing Dia. Cl. 0.0030” 0.0045”

25) Shaft and Ring Dia. Cl. 0.014” 0.017”

26) Floating Bushing and Bearing Dia. Cl. 0.0030” 0.0045”

27) Shaft and Floating Bushing Dia. Cl. 0.0045” 0.0060”

28) Bearing Carrier, Bearing and Ring Int. 0.0000” 0.0015”

29) Retainer, Main Casing and Oil Seal Dia. Cl. 0.002” 0.005”

30) Bearing Carrier and Thrust Washer Dia. Cl. 0.002” 0.005”

31) Thrust Washer and Shaft Dia. Cl. 0.060” 0.064”

32) Shaft and Bearing Carrier, Ring and Bearing Dia. Cl. 0.018” 0.021”

33) Not Shown

34) Retainer and Oil Slinger Dia. Cl. 0.014” 0.019”

35) Thrust Collar and thrust Washer Lat. Cl. 0.0080” 0.0155”

36) Retainer and thrust Washer Dia. Cl. 0.002” 0.005”

37) Oil Slinger and Impeller Dia. Cl. 0.015”

38) Oil Slinger and Oil Seal Dia. Cl. 0.018” 0.023”

39) Oil Slinger and Impeller Long. Cl. 0.005”

40) Oil Seal and Impeller Rad. Cl. 3/32”

41) Oil Seal and Main Casing Dia. Cl. 0.0005” 0.0025”

42) Oil Seal and Impeller Long. Cl. 0.012” 0.018”

43) Main Casing and Air Discharge Casing Dia. Cl. 0.001” 0.005”

44) Main Casing and Air Discharge Casing (Nuts Loose) Gap 0.004” 0.014”

45) Turbine Disc and Shroud Ring (Cold) Dia. Cl. 0.034” 0.048”

46) Gas Inlet Casing and Main Casing Dia. Cl. 0.002” 0.008”

Note: All diametrical clearances to be equalized radially.

APPENDIX D

MODEL 131 TURBOCHARGER ROTOR ASSEMBLY TABLE OF CLEARANCES

REFER TO ILLUSTRATION #2

1. Thrust Disc 8. Blower End Oil Slinger

(screw type)

2. Thrust Collar 9. Shaft

3. Impeller 10. Tablock

4. Inducer 11. Turbine Blade

5. Nose Piece 12. Ferrule

6. Ring Nut 13. Stub Shaft

7. Lockwasher 14. Nut and Cotter Pin

Measurement Location Minimum Maximum

A) Ferrule and Stub Shaft and Ferrule and Turbine

Disc

Dia. Cl. 0.005” 0.010”

B) Turbine Disc and Shaft Int. 0.000” 0.002”

C) Oil Slinger and Impeller Dia. Cl. 0.015”

D) Oil Slinger and Impeller Long. Cl. 0.005”

E) Impeller and Inducer Long. Cl. 0.010” 0.020”

F) Impeller and Inducer Int. 0.000” 0.002”

G) Nose Piece and Shaft Dia. Cl. 0.0004” 0.0012”

H) Shaft to Impeller Dia. Cl. 0.0000” 0.0006”

I) Oil Slinger and Shaft Dia. Int. 0.0000” 0.0006”

J) Thrust Collar and Shaft Dia. Cl. 0.0003” 0.0009”

Note: All diametrical clearances to be equalized radially.