API Rp 687 1st Ed 2001 - Rotor Repair Inspection

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API RECOMMENDED PRACTICE 687

 Note: Items Items such such as pitting, pitting, erosion erosion,, and corrosion corrosion may may not show show up as an indication using the NDE methods in this section. Visual examination and engineering judgement is generally required to evaluate the acceptability of the component.

8.2.1.2 The vendor shall review the design of the equipment and impose more stringent criteria than the generalized limits required in 8.2.2 through 8.2.4 if necessary. 8.2.1.3 Dispositions of indications larger than those acceptable for the applicable procedures in 8.2.2, 8.2.3, and 8.2.4 shall be mutually agreed upon between the vendor and the owner. 8.2.1.4 Refer to ASTM E 1316 for standard terminology used in nondestructive examinations. 8.2.2 8.2 . ..2

Radiogr Rad a iograph ogra og aphy p y

Radiography is generally not used to evaluate rotor components due to the complex geometry. The other techniques as outlined in this section are more suitable to evaluate the com ponent..  ponent

8.2.3 .2.3 Ultras Ultrasonic onic Inspect Inspection ion 8.2.3.1 Ultrasonic inspection shall be in accordance with Section V, V, Articles 5 and 23, of the ASME Code. 8.2.3.2 The acceptance criteria used for Ultrasonic Inspection shall be per MIL-STD-2154 Table Table 6 Class AA.

8.2.4 .2.4 Magnetic Magnetic Partic P Particl article le e and Liquid Pene Penetrant trant Inspections 8.2.4.1 Wet magnetic particle inspection shall be used and in accordance with ASTM E 709. Comment: Generally for rotor components, the dry method is not used due to the problems with arcing on finish machined surfaces.

8.2.4.2 Demagnetize all components. Measure and record residual magnetism on all components. Maximum allowable residual magnetism is ±2.0 gauss, as measured with a digital gauss meter and Hall-type probe. 8.2.4.3 Liquid penetrant inspection shall be in accordance with Section V, Article 6, of the ASME Code. Ref. ASTM E 165. The sensitivity is to be Level 3 per ASTM E 1417. 8.2.4.4 Generalized acceptance criteria used for magnetic  particle  parti cle and liqui liquid d penetr penetrant ant inspec inspections tions shall be used in accordance with Table 1.8-1. This table lists the maximum acceptable size and distribution of indications.  Note: The criteri criteriaa in Table 1.8-1 is applicab applicable le to to many many differe different nt comcom ponents of the rotatin rotating g equipment. equipment. Refer Refer to to Chapters Chapters 2 through through 7 for  specific application of the criteria.

8.2.4.5 All non-magnetic components shall be fluorescent dye penetrant inspected. All ferro-magnetic components shall  be wet wet magnetic magnetic partic particle le inspecte inspected. d.

Table 1.8-1—G 1.8-1—Genera 1.8-1— 1.8-1—General Generalize eneralized lized ized d NDE Acceptance Acceptanc Acceptance e Criteria Criteria Inspection Method Maagnetic gnetic Particle Particle

Type Indication

Severity A

B

C

n non on llinear  inear

1.6 mm (1/16 i  in n.)

2.4 mm (3/32 i  in n.)

3.2 mm (1/8 in.)

liinear  near

0.8 mm (1/32 i  in n.)

1.2 mm (3/64 i  in n.)

1.6 mm (1/16 in.)

2

2

3

and Liqu Li iquid quid id Pe Pene Penetr netran trant ant

Numb Nu Number mber er of of iin indi ndica dicati cation tions ons  per 645 mm (in.2)

General: 1. Crack like like linear indicati indications ons are cause for rejecti rejection on 2. Two or more more indicatio indications ns within within 3 D (where  D is the length or maximum diameter of the larger of the indications) shall  be considered considered a single single indication indication whose size size is the smalles smallestt diameter diameter that that can can contain contain all indica indications tions in in that group. 3. All indications indications greater greater than 0.4mm 0.4mm (0.015 in.) shall shall be reported. Severity: A: Applicable to rotating components with critical stress regions such as shaft journals, coupling hub regions, integral thrust collars, and fillet regions of the shafts and tie bolts. B: High stressed rotating components such as tie bolts, coupling hubs, and shaft oil seals. C: Moderately stressed areas of rotating components or high to moderately moderately stressed stationary components such as shaft/ rotor main bodies.