The Superior Quality of Older Pipe

Over the past 27+ years, CorrView International, LLC has performed numerous ultrasonic investigations of either very old pipe installed in the early 1900’s, or at properties where a combination of old and new pipe exist.  That work offers a remarkable demonstration of how low cost foreign imports and excessive environmental controls and regulations over U.S. manufacture have reduced the quality and corrosion resistance of today’s steel piping products.

Combined with less tolerant engineering practices, thinner pipe materials, cost cutting aka value engineering, less effective corrosion inhibitors, as well as other factors, most new piping installations can be expected to provide significantly less service life than those built many decades earlier.

• The Superior Quality Of Older Pipe

First and foremost is the unquestionable superiority in quality and corrosion resistance of pre World War II steel pipe to that manufactured today – whether foreign or domestic.  Our ultrasonic testing of steam systems from 1911 have shown a minimal loss of only perhaps 20% from the original wall thickness.  Testing of some galvanized steel domestic water risers from 1920 have documented little if any wall loss and no loss of the zinc protective coating.  In one of our oldest investigations of a galvanized steel domestic cold water riser installed in 1896, only in 2014 did it finally indicate the need for replacement!

We have certified 80 year old steam condensate pipe, which traditionally suffers from the acidic conditions of condensate requiring frequent replacement, as useful for another 50 years of service. Condenser water systems from the early 1940’s have been documented to corrode at below 1 mil per year (MPY) and offer almost unlimited future service – even at building locations where chemical treatment was poor or non-existent.  In one example of unpainted and uninsulated wrought iron cooling tower pipe, exposed to the environment and constant tower over spray for 45 years, not only was the surface rust minimal but the stenciled on ASTM pipe stamp was still clearly present – a remarkable illustration to the natural corrosion resistance of wrought iron pipe.

Wrought iron ASTM A 72 pipe, which is well recognized and documented to provide extremely long life due to its internal grain structure and inherently high corrosion resistance, can be found at many older pre-1970 properties.  However, it was removed from U.S. production in 1968 and is no longer available.

In the photograph at left we show an example of 12 in. wrought iron condenser water pipe installed in 1933.  The pipe provided summer service for 30 years during a time when chemical water treatment was almost unknown.  A new refrigeration plant and cooling tower resulted in the pipe being cut and abandoned for 52 years; the example at left exposed on the roof for half a century at both sides with no protection whatsoever.  As the photograph shows, the rough flame cut end shows no corrosion product whatsoever.

When called in by consulting engineers to explore whether this 83 year old pipe could again be used to tie in an auxiliary tower, we documented the extra heavy pipe as having a wall thickness still exceeding its ASTM specification when new 83 years prior.  To everyone’s surprise except ours, this 83 year old abandoned pipe was substantially heavier than the undersized standard grade pipe being fitted up to it.  An undersized wall thickness of 0.329 in. for the new pipe bundled on a skid vs. 0.534 in. for the 83 year old stock.

• Bethlehem Steel

Any property owner can rest easier where Bethlehem wrought iron pipe is still in use – as it provides virtually unlimited service due to its superior quality and natural corrosion resistance.  We have documented 12 in. Bethlehem Steel pipe still serving open condenser water service since 1936; having its pipe wall still near new extra heavy specifications of 0.500 in.  A recent investigation of a 1965 property having Bethlehem steel pipe installed throughout the HVAC systems, still showed wall thickness in most examples at or exceeding its new ASTM factory specifications after almost 50 years of service.

We consider Bethlehem Steel pipe products as the best ever manufactured.  Bethlehem Steel helped build the United States and won two World Wars.  Today, what remains is a gambling casino, destroyed by extreme government and environmental regulations, excessive union demands, in combination with impossible to compete against low cost, subsidized foreign pipe imports.  Now, many decades later, the abandonment of high quality in favor of lowest cost has been revealed in many of the large scale piping failures we document.

Although today’s steel manufacturers still meet the same ASTM specification, unknown and unexplained differences exist to produce products which are vastly different in terms of their corrosion susceptibility.  Some metallurgical labs and corrosion “experts” have vehemently argued that today’s steel products are exactly the same as pipe produced in 1910 due to it meeting the same ASTM specification.  Simple observation and over 25 years of comparative ultrasonic investigations between new and old pipe, however, have overwhelmingly proven otherwise.

Below we show various examples of older pipe serving continuously for as long as 111 years, and still capable of providing another 200+ years of service or more. The remainder of this Internet site documents generally more recent piping systems, and their associated corrosion problems.

• Outstanding Older Pipe Quality

1928 – Fire sprinkler 6 in. main supply line showing minor cosmetic corrosion and with its wall thickness still at new ASTM schedule 40 specifications of 0.280 in.	1964 – Chill water service 12 in. pump supply line. A light coating of oxidation and scale exists with high and uniform wall thickness still near new standard grade specifications.
1921 – Saved coupon cut-out from 8 in. fire sprinkler main showing some minor internal deposits but with extremely high and uniform wall thickness still near new schedule 40 specifications of 0.322 in.	1901 – Steam and condensate one pipe horizontal 4 in. main – likely the worst possible conditions for a steam system. Only minor bottom pitting is present after 111 years of seasonal steam heating service.

More photos on pipe quality are shown in our Photo Galleries.

© Copyright 2023 – William P. Duncan, CorrView International, LLC