API 570 Questions 19

1.

An eigh eightt-inch inch diam diame eter ter pip piping ing syst syste em is inst instal alle led d in Dece Decemb mber er 1979.The installed thickness is measured as 0.34”. The minimum thickness ! the pipe is 0."0”. 0."0”. #t is inspected in Dec$%3 and the the thic thickn knes ess s is !un !und d t be 0.3 0.3"” "”.. An An insp inspec ecti tin n Dec Dec$% $%7 7 re&eals a lss ! 0.01” !rm the 1"$%' inspectin (as during Dec$%9 the thickness (as !und t be 0."9”. The last inspectin (as during Dec$9' and the thickness (as !und t be 0.")”. *hat is the lng-term crrsin rate ! this system+ a, b, c, d,

".

sin sing g the the in! in!rm rmat ati in n in ues uesti tin n ab ab&e &e// calc calcul ulat ate e the the s sh hrt rt-t -ter erm m crrsin rate. a, b, c, d,

3.

0.00'”$year 0.007'”$year 0.0037'”$year 0.00"'”$year

sing the shrt-term crrsin rate in determine the remaining li!e ! the system. a, b, c, d,

4.

0.00'”$year 0.007'”$year 0.0037'”$year 0.00"'”$year

uestins

ab&e/

1% years 1' years 1" years ne ! the ab&e

reheating t nt less than22222222222 degrees  may be cnside cnsidered red as an altern alternati ati&e &e t pst (eld heat heat treatm treatment ent !r alteratins r repairs ! -1/ piping initially pst (eld heat treated as a cde reuirement may nt be used i! the piping (as (as pst pst (eld (eld heat heat trea treate ted d due due t en&i en&ir rnm nmen enta tall crac cracki king ng pre&entin, a, b, c, d,

1'0 "00 300 3'0

'.

#! an 5intelligent pigging” system is used t inspect buried piping/ (hat type ! bends is usually reuired in the piping system+ a, b, c, d,

).

6( !ten shuld prly cated pipes (ith incnsistent cathdic prtectin ptentials ha&e a pipe-t-sil ptential sur&ey made+ a, b, c, d,

7.

i&e diameter bends 90 degree pipe ells Ten diameter bends Three diameter bends

early 8&ery " years 8&ery ' years 8&ery 7 years

uried piping inspected peridically by e:ca&atin shall be inspected in lengths ! 222222222222 !eet at ne r mre lcatin ;udged t be mst susceptible t crrsin. a, b, c, d,

" 4 ) %

t t t t

4 ) % 10

%.

A buried piping system that is nt cathdically prtected has t ha&e an inspectin inter&al set. The sil resisti&ity is checked and !und t be 3400 hm$cm. As the inspectr/ (hat inter&al (uld yu set+ a, b, c, d,

9.

#! a piping system is made up ! unkn(n materials and cmputatins must be made t determine the minimum thickness ! the pipe/ (hat can the inspectr r the piping engineer d t establish the minimum thickness+ a, b,

c,

d,

10.

".' years 7.' years ' years 10 years

The l(est grade material and ;int e!!iciency in the applicable cde may be assumed !r calculatins.