ML20088A865

Forwards Revised Response to Control of Heavy Loads, Technical Evaluation Rept Re Recommendation/Open Item 2 on Insp Program for Reactor Vessel Head Lift Rig & Upper Guide Structure Lift Rig

ML20088A865
Person / Time
Site:	Fort Calhoun
Issue date:	04/05/1984
From:	William Jones OMAHA PUBLIC POWER DISTRICT
To:	John Miller Office of Nuclear Reactor Regulation
References
REF-GTECI-A-36, REF-GTECI-SF, RTR-NUREG-0612, RTR-NUREG-612, TASK-A-36, TASK-OR LIC-84-091, LIC-84-91, NUDOCS 8404130243
Download: ML20088A865 (3)

Text

.

a l

Omaha Public Power District 1623 Harney Omaha. Nebraska 68102 402/536-4000 April 5.1984 LIC-84-091 Mr. James R. Miller, Chief U. S. Nuclear Regulatory Commission Office of Nuclear Reactor Regulation Division of Licensing Operating Reactors Branch No. 3 Washington, D.C.

20555

References:

(1)

Docket No. 50-285 (2) letter OPPD to NRC (Jones to Clark) dated September 1,1983, LIC-83-222

Dear Mr. Miller:

Fort Calhoun Station Unit No. 1 Control of Heavy Loads, Phase I On May 17, 1983, the Commission provided Omaha Public Power District with a draft Technical Evaluation Report (TER) written by Franklin Research Center.

Based on this TER, a commitment was made (Reference 2, " Response to Open Item 2") to develop an inspection program for the reactor vessel head lift rig and upper guide structure lift rig.

Subsequent to our response, telephone conversations were held on February 29 and March 18, 1984, with your staff and technical reviewers in an effort to resolve the remaining open items.

Specifically, the District was requested to:

(1) make a commitment to do NDE on all critical welds on the reactor vessel head lift rig, and (2) provide justification for not doing a 150% load test. As a result of these conversations, the District is revising the response to Recommendation /Open item #2. This revised response is attached and should replace the previous response found in Reference 2 (" Response to Open Item 2").

Sincerely, d'M 8404130243 040405 hC.Jgnes PDR ADOCK 05000285 O

PDR DivisIo'ri Manager Product' ion Operations WCJ/0JM/ rh-J Attachment cc:

LeBoeuf, Lamb, Leiby & MacRae 1333 New Hampshire Avenue, N.W.

(l Washington, D.C.

20036 Mr. E. G. Tourigny, Project Manager Mr. L. A. Yandell, Senior Resident Inspector Empioumenigngqua,i opponunau 45suo

o

==

REVISED RESPONSE TO RECOMMENDATION /0 PEN ITEM #2

References:

1)

NRC Letter dated May 17, 1983

2) OPPD letter No. LIC 81-222 (page 2) dated Sept.1,1983 In order to resolve Open Item #2, we propose the following:

(A)

Inspection Program:

1) The District will develoo an inspection program for the reactor vessel closure head and upper guide structure lift rigs.

The program will include visual inspection on all exposed welds on the reactor ves-sel head lift rig and upper guide structure lift rig during every re-fueling outage.

This program will be implemented durinn the 1984 re-fueling outage.

2)

In addition, non-destructive testing (NDT) will be performed on all critical welds on the reactor vessel head lift rig at an interval not exceeding five refueling outages.

Criteria for evaluating welds shall be per the industry codes.

The critical welds on reactor vessel head lift rig are identified be-low:

No.

Weld Connection Type of Weld No. of Welds 1.

Lifting Eye & Lugs (3)

Full Penetration

'3 (Two Welds per Lug)

Weld 2.

Corner Plates (3) &

Fillet Weld -

6 Pipe (3)

(Two Welds per Location) 3.

Tubing Lifting Eye & Tube Fillet 3

4 Tube & Tube Shell Fillet 30 (10 Welds per Location, 3 Locations) 3)

If any major repairs are required, the welds will be repaired per approved procedures. Non-destructive testino will be performed again to verify that the welds are acceptable. The lift rig.shall be 100%

load tested for actual load after any major repairs and inspected in accordance with ANSI N14.6-1978 Section 5.3.1-(1).

4) Section 5.3, 5.4 and 5.5 of ANSI N14.6-1978 will be used as guid-ance when these procedures are written. These inspections will be per-formed and documented by quality control' personnel.

e I

l Open Item #2 Page Two (B) Load Test:

Per our engineering judgment, the District believes that a 150% over-load test on the reactor vessel lift rig as recommended per this open item will not result in any significant improvements in the safety of load handling operations at the Fort Calhoun Station.

This conclusion is based on the following:

1) An engineering evaluation was conducted on the design parameters specified for the lift rig.

It was concluded that the design stress margins were substantial.

2) The mechanical design is comprised of a simple welded tripod frame which is connected to a cylindrical shell (attached to the RV head) f with alignment pins. These pins are the only mechanical joints which require assembly when engaging the lif t rig to the shell. Thus, due I

to the simplicity of the design, assembly error is highly unlikely.

3) The critical welds on the lift rig have been identified and the District shall perform Nondestructive Examinations (see item A above) at an interval not exceeding five refueling outages.

4) The lif t rig was manufactured and supplied by a reputable NSSS vendor, (Combustion Engineering).

i.

5) The lift rig has been used over the last 10 years without any signs of degradation.

Based on the above. the District takes exception to doing a 150% load test.

4

.-.m.