Text

Insp Rept 50-410/85-42 on 851112-15 & 1204.Violation Noted: Installation of Coaxial Cable by Unauthorized Method & Min Bend Radius for Installed Flex Conduit & Coaxial Cable Exceeded
	ML17055B142
Person / Time
Site:	Nine Mile Point
Issue date:	01/07/1986
From:	Anderson C, Paolino R; NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
To:	;
Shared Package
ML17055B140	List: ML17055B139; ML17055B141; ML17055B142;
References
	50-410-85-42, NUDOCS 8601270160
	Download: ML17055B142 (26)
	v • d • e

U.S.

NUCLEAR REGULATORY COMMISSION

REGION I

Report

No.

50-410/85-42

Docket No.

50-410

License

No.

CPPR-112

Priority

Category

1 Systems

unless

noted otherwise.

The inspector

reviewed the conduit layout

drawings

EE-570E,

D and

G which specifies stainless

steel flexible

conduit.

Where the specification

E-061A calls for the use of flexible

conduit it limits the length of flexible conduit to 48 inch whether

it is connected

at one

and or both ends.

However, the above drawings

placed

no limitations on length of flexible conduit that could be

used.

Installed lengths varied from 4 feet to 80 feet.

Engineering

justification for using flexible conduit instead of rigid conduit and

lengths of flexible conduit, in excess

of 48 inches

was not available

for this inspections

This item is unresolved

pending

NRC review of licensee

evaluation

and

justification for deviating from specification

requirements.

(50-410/85-42-01).

During the inspection of the installed Neutron Monitoring System,

the

inspector

observed that the

bend radius of a number of flexible conduits

exiting out of the top of junction box 2JB0790

were smaller than the

required

bend radius for the cable in the flexible conduit.

E-061A

specifies

a bend radius of 3 inches for the NJP-29 cable installed in

the flexible conduit.

t

The conduit manufacturer

(American Boa) allows

a minimum bend radius of

1'," for this application.

As

a result of using the flexible conduit

allowable

bend radius the licensee violated the permanent

bend radius

allowed by the cable manufacturer.

Flexible conduits violating bend

radius include:

2CX998A thru H, J,

K,

M & P thru

R.

Additional bend

violations were identified in the drywell but outside of the Reactor

Vessel

Pedestal

area

as follows:

Flexible Conduit:

2XK997YH1, minimum required

bend radius

5 inch,

was

2 3/4 inch

2CK997YF, minimum required

bend radius

3 1/2 inch,

was

2 1/8 inch

2CC996YC5,

minimum required

bend radius

6 inch,

was

2 3/4 inch

2CK999YD, minimum required

bend radius

3 1/2 inch,

was

2 inch

2CK9997YG,

minimum required

bend radius

3 1/2 inch,

was

2 inch

The licensee

was informed that the above

bend radii were. examples of

failure to follow procedures

and in violation of 10 CFR 50, Appendix B,

Criteria

V which states,

in part, that:

"activities affecting quality

shall

be prescribed...and

shall

be accomplished

in accordance

with

these instructions..."

(50-410/85-42-02).

3.0

Instrumentation

Cable

and Termination

- Work Observation

3. 1

The inspector

observed

work activities in progress,

completed work and

partially completed

work relating to the installation of the Neutron

Monitoring System to ascertain

whether the installation

was performed

in accordance

with applicable

procedures,

the

FSAR and licensee

commitments.

Items examined for this determination

include:

Rigid Conduit Nos.

2CX999YH and

2CX999YG

'Electrical Junction

Box Nos.

2JB-0790

and 2JB-0794

Coaxial

Cable

Nos.

2NMPAYX006, 2NMPAYX007, 2NMPAYX015, 2NMPAYX017,

2NMPAYX018, 2NMPAYX021, 2NMPAYX022, 2NMPABYX024 thru 030,

2NMPBYX031 thru 036

Cable Pull Tickets for the above referenced

cables

Cable

Reel

Nos.

E024B-1189,

E024B-1191

and

E024B-1194

Wiring Diagram Nos.

36A-9GA and

36B-9GA

In reviewing the cable pull tickets for the above referenced

cables,

the

inspector

noted that the

maximum pull tension for the cable

had been

omitted.

Discussions with the licensee

regarding

the requirements

in

specification

E-061A and Appendix J for calculating

and verifying the

cable pull tension,

the licensee

stated that it was not necessary

to

calculate

or verify the cable pull tension for the Neutron Monitoring

System cable

because

the cable

was

pushed

not pulled through the flexible

conduit.

Since the specification

E-061A did not address

cable install-

ation by pushing,

the inspector

requested

that the licensee

produce

documented

instruction

and procedures

used

by the cable pull crews to

push the cable through flexible conduit.

Following additional di'scus-

sions with licensee/construction

engineering

and supervisory

personnel

it became

evident that there

were

no instructions or procedures.

Personnel

present

during these

discussions

could not agree

on the

method(s)

used in attaching

the lubricating tube to the cable or whether

the coaxial

cable

was pushed,

pulled or

a combination of both.

Figure

3 illustrates four methods of attaching

the lubricating tube to the

coaxial

cable thought to have

been

used for installing the coaxial

cable.

Conclusions

reached

following discussions

with licensee/construction

engineering

and supervisory

personnel

are

as follows:

a.

There are

no written procedures

or instructions for installing

cable

by pushing.

However, Section 4.3. 1B of Quality Standard

QA 10.52 for raceway

and cable installations

states

that:

"The

engineering

department

is responsible

for issuing specification

and drawings,

and reviewing and approving instructions required

for the installation of raceway

and cable...".

b.

Figure 3-C was finally agreed

upon by construction

and

QC personnel

as the method

used in attaching

the lubrication tube to the

coaxial cable.

c.

QC personnel

present

during the cable installation

say the cable

was

pushed

through the flexible conduit.

They claim to have

observed

personnel

at the lubrication end using two fingers to

guide the lube tube

as it was being

pushed

back out of the flexible

conduit from the opposite

end.

d.

Cable pulling craftsman

and foreman (day/night shifts) differ on

whether the cable

was pushed

or pulled.

Day shift personnel

say

cable

was pulled as evidenced

by 2-3 breaks

occurring during the

installation of the permanent

cable.

The breaks

were said to

have occurred in the coaxial center conductor

loop attachment

to

the lubrication tube (figure 3-C mark X).

Night shift personnel

say cable

was

pushed

through while using

two fingers to guide

the lube tube out of the flexible conduit.

e.

All personnel

agreed

to

some difficulty in installing the coaxial

cable.

Those that believe cable

was pulled claim

a pulling force

of 3-5 lbs

on the lubricating end

and at least

20-25 lbs pushing

at the

same time.

Others,

claiming the cable

was pushed,

say the

lube tubing was held by two fingers

and used in gui'ding tube out

while force of 30 lbs or more

on the other end

was

used to push

cable through flexible conduit.

All personnel

stated it was

necessary

to station

personnel

(h symbol in figure 2) along the

routing of the cable installation to shake

and straighten

the

curved sections

of the flexible conduit to pass

the cable through

the curved sections of the installation.

The licensee

installed safety-related

Neutron Monitoring System

cables without using documented

instructions or procedures

approved

and authorized

by responsible

engineering

personnel

to

control

and provide inspection criteria to ensure acceptability

of the work performed.

g.

The licensee

did not use tension monitoring devices

as required

by Section 3.2.3.3 of Specification

E-061A which states,

in part,

that:

"tension monitoring of manual pulls in conduit/duct is

not required providing that the conduit/duct

does not exceed

the

length specified in Table

1.

Table

1 states that'for horizontal

pulls

up to and including 270 degrees

of bends

and

25 ft 'total

length between pull points tension monitoring is not required.

The installed Neutron Monitoring System cables

exceeded

the total

number of degrees

as well as the length between pull points

as

noted in

EKDCR No.

11960.

The disposition of this nonconformance

was that the cable

was pushed,

not pulled, therefore

the

bend

and length limitations did not apply.

Based

on the above critique the inspector

determined

the coaxial

cable installation to be

a violation of 10 CFR 50, Appendix B,

Criterion V.

(50-410/85-42-03)

The inspector questioned

the licensee

regarding possible

damage

to the cable

from the apparent

push/pull type of action required

and

used to install the coaxial cable in the flexible conduit.

The licensee

setup

a typical worst case installation to demonstrate

that the cable could

be pushed

through the conduit without damaging

the cable.

December

4,

1985 was set aside

as the scheduled

demon-

stration date.

This allowed the licensee

approximately

3 weeks to

prepare

the test configuration.

4.0

Instrumentation

Cables

and Terminations

-

ualit

Record

Review

The inspector

reviewed pertinent, work and quality records for activities

relating to the installation of the safety related

Neutron Monitoring System

to ascertain

whether the records

meet established

procedures

and whether the

records reflect work accomplished

consistent with NRC requirements

and

FSAR commitments.

Areas

examined

include cable pull tickets, terminations,

nonconformances,

testing

and inspection.

Items examined for this determination

include:

Inspection

Report Nos.

E5A43806,

ESA4766,

ESA43970,

ESA43689,

ESA43775

and

E5A43688

)

Cable Pull Tickets for Coaxial

Cable

Nos.

2NMPAYX002 thru 007 and

2NMPBGX001 thru 008.

Nonconformance

Report Nos.

11015,

11960,

13190

& 11893

Quality Assurance

Inspection

Plan

No.

N20E061AFA025 revision

OG change

2

Electrical Installation Specification

No.

E-061A revision

10 dated

May 20,

1985

Quality Standard

QS. 10.52NM revision

A dated

June

10,

1985

Engineering

and Design

Change

Report

Nos.

EKDCR-12187,

C-45477,

F-02258A

and

F-12513

In reviewing the above

documents

the inspector

noted the following:

a.

Specification

E-061A, Appendix B,

on "Cable Test Procedures"

does

not

include test instructions for testing coaxial cable.

This had

been identified by the licensee

in an

EKDCR F02258 of May 15,

1985 five days after completing installation of Neutron Monitoring

System coaxial cables.

The revised

BOCR F02258A was issued

on May 31,

1985 to revise Appendix

B to include test requirements

for coaxial

and

twinaxial cable.

b.

guality Assurance

inspection reports

(IR') indicate Insulation

Resistance

readings

to verify acceptability of the installed Neutron

Monitoring System control cables

was not performed until August 10,

1985.

The megger testing for Insulation Resistance

was done prior to and after

completing cable connector

assembly.

The test data

shows that all

cables

met or exceeded

the minimum insulation resistance

requirements

listed in

EKOCR 02258A.

The equipment

used

by the licensee

was properly calibrated

and within

the calibration

due date.

The inspector

noted

some imperfection,

blemishes

on outer cable jacket

of the coaxial cable

Mark No. NJP-29.

The licensee

had identified

similar defects

as reported

in nonconformance

NKD 11893.

The report

listed

14 cable reels with surface

imperfections.

Physical

and electrical test of the cable

per specification

E024B

indicate defects

were limited to the outer jacket

and determined

to

be acceptable.

E8DCR 13190 identifies

3 cable failures attributed to moisture that

may have

been present

between

conductor, dielectric and shield.

These

cables

were retested

following a period of 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> under

a dry nitrogen

purge to remove the moisture.

Cable test results

met minimum require-

ments.

No violations were ident,ified.

5.0

Demonstration of Methods

Used for Installin

Neutron Monitorin

S stem

Coaxial

Cables

5.1

The test took place in the vendor

shop

on site on'ecember

4,

1985.

Personnel

present

during the demonstration

by craft personnel

are

noted in Details,

paragraph

1 with a *

symbol.

Figure

1 illustrates

the original test configuration setup in the vendor

shop

as being representative

of the actual installation of the Neutron

Monitoring System

under the Reactor Yessel.

Discussions

with. various

craftsmen

indicated that'they

had practice

sessions

(approximately

two

weeks)

on the installed 'configuration

and were successful

in pushing

the 'coaxial

cable through the flexible conduit.

The inspector

examined

the test configuration

and determined it was not representatives

of

C

y 'I

\\

the actual installed configuration.

Discussions with supervisory

personnel

indicated that

no one

had examined

the actual installation

or reviewed routing drawings

necessary

in determining the worst case

test configuration.

The installed test configuration was

a simple

straight line/single plane configuration having minimum bends

and not

representative

of the worst case configuration (Figure 1).

The

inspector determined

the test configuration to be unacceptable

for

determining whether the installed Neutron Monitoring System coaxial

cables

were

pushed

or pulled through the flexible conduit.

Figure 2,

more closely illustrates the changes

requested

by the inspector

based

on photographs

taken of the actual installation under the Reactor

Vessel.

Although the changes

made

were not entirely representative

of the worst case conditions

found under the vessel, it was agreed

that the configuration of figure

2 was representative

of the majority

of the installed cables.

One difference

(and

an important difference)

being the spacing

between

each

succeeding

bend.

The installed flex-

ible conduit bends

under

the Reactor

Vessel

were

spaced

much closer

(by at least

1/2 of the distance)

than the spacing

between

bends in

the test setup.

.The length of the flexible cable

used in the test

setup

was established

at 60 feet for the 3/4 inch flexible conduit

and

65 feet for the 1/2 inch flexible conduit.

Some craftsmen

had

indicated the actual installed lengths to be as

much as

80 feet.

The

simulated

bends

and angles

were formed by attaching

the flexible

conduit with cable ties to the supports installed in the Comstock

Electrical

shop.

The total

number of bends

was conservatively

estimated

to be 800 degrees.

To aid in passing

the cable through the flexible conduit,

a lubricant

was used.

The lubricant was applied through

a 1/4 inch tygon (semi-

rigid) tubing using

80 psig air regulated

to 45 psig

so that the lubri-

cating fluid just oozed out of the

end of the tygon lube tube.

The

tygon lube tube (approximately

80 feet long) had

been pulled through

the 3/4 inch flexible conduit using what is commonly

known as

a fish

line.

The fish line is

a solid 1/8 inch diameter flexible plastic

line pushed

through the flexible conduit.

This line is then attached

to the semi-rigid lube tube

and pulled back through the flexible con-

duit.

Lubrication fluid oozing out of the end of the lube tube

as it

is pulled through the flexible conduit reduces frictional resistances

allowing tube to be pulled through the flexible conduit.

To further assist

in installing the coaxial cable

and demonstrate

that

the coaxial

cable

was

pushed

through the flexible conduit, craftsmen

(indicated in Figure

2 by h) were placed along the routing of the

flexible conduit to straighten

and

shake

the flexible conduit as the

cable

passed

through these

areas.

5.2

To start the test,

the craftsmen

stopped

the flow of lubricant .through

the lube tube

and disconnected

the fish line.

The lube tube

was then

attached

to the larger coaxial

cable

(RSS-6-116/LE)

per figure 3A.

The lubrication fluid was set in motion again

and the cable

was inserted

into the 3/4 inch flexible conduit at the junction box.

Craftsmen at

the other

end proceeded

to guide the lube tube out of the flexible

conduit.

No visible force was observed

as the coaxial 'cable

was pushed

through the straight section of flexible conduit from the junction

~ )

box to the first bend (Figure 2).

After entering the first bend the

two finger'old

on the lube tube

became

one

hand hold then

two hands

with visible exertion of force

on both ends.

The inspector attempted

to push the cable at the junction box end, exerting approximately

20-25 lbs.

Going to the opposite

end, it was determined that

a force

of 5 or more lbs was needed

to pull on the lube tube.

During this

same

time the craftsmen

stationed at various points (6 Figure 2)

along the cable route

had to continually shake

and straighten

various

sections of the flexible conduit to assist

in getting the cable through.

The force required to pull on the lube tube increased,

requiring both

hands

as the cable

passed

through the multiple bend areas

(Figure 2).

At no time was it possible to push without pulling the coaxial cable

through the flexible conduit once the cable

had gone through the first

bend following the junction box.

The time required to pull the coaxial

cable

(RSS-6-116/LE,

NJP-32)

through the 3/4 inch flexible conduit was

6 minutes.

5.3

The demonstration

for installing the coaxial cable

RSS-6-104,

NJP-29

was delayed

pending the installation of the

65 feet 1/2 inch flexible

conduit.

While waiting for the replacement

of the installed shorter

conduit test length (35 ft., Fig. 1),

a dynamometer

was

made available

and

used to measure

the force required to withdraw the previously

installed coaxial

cable

RSS-6-116/LE,

NJP-32.

The lubricant flow had

been

stopped

and the lube tube disconnected

from the cable.

The dyna-

mometer (weighing 7.5 lbs) was fastened

(Fig. 2) to the coaxial

cable

and the cable withdrawn by pulling uniformly on the dynamometer.

The

forces registered

on the dynamometer

were in the 30-35 lb. range to

start,

tapering off to 10-20 lbs. in passing

through the last two bends

prior to the junction box.

Allowing for the weight of the dynamometer

and the

use of lubricant during the push/pull installation of the cable,

the inspector

concluded that the

maximum allowable (calculated)

pull

tension

(69 lbs.) was not exceeded

for the installation of the

RSS-6-116/LE(NJP-32)

coaxial cable.

Having replaced

the short length (35 feet) of 1/2 inch flexible conduit

with the

65 foot length,

the craftsmen

were ready to proceed with the

installation of coaxial

cable

Mark No. NJP-29.

The

same

procedure

was followed for inserting the fish line and drawing

the lubrication tube through the 1/2 inch flexible conduit.

The attach-

ment to the lube tube

was identical (Figure 3-A).

The lubrication medium

was set in motion using the

same criteria

so that the flow just oozed

out of the lube tube.

The craftsmen

inserted

the cable

(Mark No. NJP-29)

into the 1/2 inch flexible conduit at the junction box end.

pushing

the cable to the first bend.

During this process

the lube tube

was

eased

out, of the conduit applying just enough tension to keep the cable

from backing

up.

The cable/lube

tube

movement

was

smooth

up to the

first bend.

At this point force

had to be applied to push the cable

while exerting 3-5 lb pull tension at the lube tube

end.

Craftsmen

tried to push the NJP-29 cable through after passing

the first bend

but were unsuccessful.

It was evident that the lube tube

had to be

pulled out and that the coaxial cable

Mark No.- NJP-29 could not be used

to push the lube tube through the conduit.

Here again,

craftsmen

had

to be positioned

(6 Figure 2) along

the. conduit routing to vigorously

shake

and straighten

the curve section of the flexible conduit to

complete

the installation.

to push the

6.0

Unresolved

Items

The conclusion following both tests is that the coaxial cable could

not have

been

pushed

through the installed configuration.

Tension

had to be applied to pull the cable through.

The amount of tension

(Approximately 3-5 lbs) is much less

than the calculated

allowable

pull tension for cable

Mark No.

NJP-29

(35 lb) and therefore it may

be concluded that there

was

no damage

to the cable.

This has

been

verified through insulation resistance

tests

per

E8DCR 02258A.

One

additional test

was performed to determine if the cable without the

lubrication tube could

be pushed

through the flexible conduit.

The

coaxial

cable

Mark No.

NFP-29

was released

from the lube tube

and

withdrawn from the flexible conduit.

Starting from the

same point at

'the junction box the cable

was

pushed

through the flexible conduit in

approximately

6 minutes.

Craftsmen did vigorously shake

and

straighten

the curved sections

in the conduit but they were able to

push the cable through indicating

much of the problem in trying to

push the cable

was in trying to push the

much more rigid lube tube

ahead of the softer,

more flexible coaxial cable.

The force required

coaxial

cable

mark no.

29 was estimated

to be 15-20 lbs.

Unresolved

items are matters

about which more information is needed

to

determine

whether it is acceptable

or

a violation.

Unresolved

items are

discussed

in paragraph

2.0.

7.

~Ei

The inspector

met with the licensee

and construction

representatives

(denoted

in Detail, paragraph

1.0) at the conclusion of the inspection

on November

15,

1985 and at the demonstration

of December

4,

1985, at the construction

site.

The inspector

summarized

the findings of the inspection

and the

licensee

acknowledged

the inspectors

comments.

At no time during the inspection

was written material

pro'vided to the

licensee

by the inspector.

COMSTOCK SHOP

Unistrut/Pipe Supports

Suspended

from Ceiling

4" Rigid Conduit

Representing

7ft

Penetration

thru

Reactor

Vessel

Pedestal

Cable Ties

Used

To Attach Flex-Conduit

o Supports

I/2" American

BOA

Flex-Conduit

(35 ft',

3/4" American

BOA

Flex-Conduit

(60 ft)

Junction

Box

Original Test Configuration

FIGURE

1

~

COMSTOCK SHOP

Bends - A

roximate

Degrees

Unistrut/Pipe Supports

Suspended

From Ceiling

90

7 ft Penetration

.Representing

Penetration

'throu

h Reactor

Yessel

9

Pedestal

to

\\

80

18

45

5 ~

3/4" American

BOA Flex-Conduit

60 ft

In

1/2 American

BOA

lex-Conduit

(65 ft)

~ 1/4" Tyson Lube Tube

Lubricant Flow Adjusted

> To Ooze Out of End of

~Tubing

Junction

Box On

Outer Shield

Mal 1

.Cable Entry Point

Pressure

Regulated

to 45 PSI

80 PSI Air

Coiled Cable

Cut

To Length

Dynamometer

Revised Test Configuration

Legend:

X - Cable ties securing flex-conduit to unistrut

- Personnel

pulling/pushing cable

and lube tube thru flex-conduit

~ - Personnel

assisting

movement of cable through flex-conduit by

shaking twisting flex-conduit

C3 - Personnel

coiling cable

FIGURE 2

e

'Several

Layers of Electricians

Stranded

Conductor with Insulation

Tape

Wrapped Around Connection

I/4" Tygon Tubing

A

Coaxial

Cable

FIGURE 3

E(

ML17055B142

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