More than 100 years ago, high pressure steam was the primary form of power driving manufacturing needs. At the time, the growing industrialization of America fueled the demand for this form of power and with it frequent corrosion induced boiler explosions. Back then, such catastrophic explosions were simply regarded as both "an inevitable evil" and "an act of God."
On March 20, 1905 one such boiler explosion at a Massachusetts factory killed 58 persons, injured 117 others, and caused $250,000 dollars worth of property damage.
The entire Emerson Shoe Factory was oblitherated to the ground, as well as were nearby homes and other structures. It was an intolerable and worsening situation.
In response, manufacturing and operating standards for steam boilers were established in various states, and by 1915, a uniform code defining their construction was adopted by the Council of the American Society of Mechanical Engineers, ASME.
With less understanding of the issue and capacity to reduce corrosion activity then available, interest also turned to monitoring and measuring the wall loss within the boiler before it reached explosive limits.
In those earlier days of high pressure steam boilers, extremely small "tell tale" holes were drilled partially into its shell and heads from the outside in order that a tiny but noticeable leak would develop after internal corrosion had reached a certain pre-defined point through its internal wall.
The theory was that as the internal wall deteriorated, it would meet the partially drilled hole, develop a small but controllable leak, and thereby signal plant operators that the vessel wall had reached that predefined point where further operation was unsafe. Then, the boiler could be removed from service before deteriorating further and potentially exploding. It was a simple yet effective test method.
The below design drawings from this early United States Patent illustrates a later variant of the tell tale idea whereby a malleable plug was threaded into the boiler shell or heads (10) to a pre-defined depth, also known as a "blind hole." As the interior boiler wall eventually corroded away to reach the face of the device (11) and its opening (15), water or steam would pass through a small capillary tube (14) leading to the atmosphere; signaling that sufficient wall loss had occurred to raise a threat.
Unlike the earlier method of simply drilling a blind hole with no means to stop the leak once it started, the end of this device (16) was made of a softer material such as brass - thereby allowing it to be peened closed with a hammer and the leak stopped.
While the earlier tell tale holes presented certain inherent problems, such as stopping the leak once it started, they did offer perhaps the most accurate corrosion warning system ever developed since it was the steel plate of the boiler itself deteriorating under true internal corrosion conditions. Such pre-drilled tell tale holes were actually the first corrosion monitoring devices patented back in the early 1900's for steam boilers and pressure vessels. Although no longer employed, they still unquestionably remain as one of the most accurate indicators of corrosion loss.
Having a predefined wearable surface, CorrView basically acts like the drilled tell tale hole from a over a century ago. CorrView provides the wearable surface dimension and allows for a similar failure event to occur once its front surface has corroded away - but instead safely contains the leak within its fully sealed, high pressure rated sight glass. Water or moisture entering into its core then triggers a high visibility warning indication at its clear front viewing window. It is essentially a portable tell tale device.
Physically, the CorrView corrosion monitor is similar in form to a standard hex shaped pipe plug - except that is has a sight glass window, a hollow interior chamber, and water contacting thin wearable metal surface.
Under normal conditions, this sight window shows a white color signifying normal monitoring status. As long as the wear dimension of the liquid inserted side of CorrView remains intact, the sight window will always remain white. This normally occurring or default color may remain for one year to many decades - all depending upon the level of corrosion within the pipe or tank, in combination with its wearable dimension.
For example, a standard CorrView unit having a 0.040 in. wear dimension and installed into a chilled water system having a corrosion rate of 0.3 MPY would easily last many decades. And during that entire time reassuring owners / operators that wall loss had not progressed past that minimum defined amount.
Manufactured on a computer controlled CNC machine from a solid piece of bar stock, the forward surface of CorrView is precision machined to provide a fixed wall thickness at its front. This is typically 0.040 in. for condenser water and fire protection applications, or any thickness dimension specified.
CorrView remains in place, constantly wearing thinner depending upon the interior piping environment, and will signal a bright visual alarm should a high corrosion condition produce sufficient wall loss exceeding its wear dimension. The ability to vary the wall thickness dimension at its front surface provides great flexibility in monitoring needs.
Once the forward or liquid inserted side of CorrView corrodes sufficiently to produce a water or moisture leak into its interior cavity, the normal white color at the sight window turns bright fluorescent orange - signifying a failure condition at its water contacting surface and a likely corrosion problem.
CorrView's vivid color change can be seen at distances well exceeding 40 ft., and provides a universally recognized signal that a problem condition exists. This color change is permanent and non-reversible.
Each CorrView corrosion monitor is provided with a bright two part identification tag to both identify its purpose, and to also direct any watch engineer or supervisor of exactly who to notify. The tag is self laminating to protect the contact information from moisture or environmental damage, with the bottom tear off stub providing further tracking information.
Its that simple - making CorrView the perfect addition to every corrosion monitoring program. It especially offers benefits to those smaller or less critical piping systems or tanks which, though they may not represent a serious corrosion threat, still warrant some attention.
Requiring no flow, CorrView is ideally suited to monitoring areas of inherently higher corrosion activity such as at fire protection systems, and under no flow, dead end conditions.
Standard forms of CorrView are CNC machined from solid bar stock of the equivalent to ASTM A 53 grade B mild steel - the most commonly used material in HVAC, fire sprinkler, process water piping, and many recirculating systems, and similar to ASTM A53, A106, A135, and A795 in terms of corrosion susceptibility. Our standard model is available in U.S. pipe thread size 1-1/2 in. NPT - making it ideal for most HVAC piping, fire protection, and process water systems.
A clear quartz sight glass at the front of CorrView provides the window through which indication of a problem condition is shown. This sight glass, commonly supplied for high pressure applications, is thermally fused into the steel itself, and is custom manufactured to strict specifications. It is impact resistant, and has been tested to over 10,000 PSI - well beyond any operating limits and thereby safely containing any internal piping pressures. View a Pressure Test report.
During extreme condition testing for arctic applications in Canada, whereby a fully water filled CorrView unit was frozen solid, the 0.100 in. thick wearable steel surface bulged due to the tremendous internal pressures of the expanding ice, estimated at over 7,000 PSI. Yet the fused sight glass never cracked or leaked.
Under normally low corrosion conditions, CorrView may remain in place for decades without change. Similar to an electrical fuse for any power circuit, CorrView remains passive to provide peace of mind that high wall loss is not occurring. Under high corrosion conditions, however, and especially where strict corrosion control has not been maintained, CorrView will provide years of advance notice that a problem exists.
CorrView is a single use only device - to be removed and disposed of after a warning indication has taken place. Until that time, it provides a cumulative measurement of wall loss. In effect, CorrView acts as a virtual "Pipe Fuse" - remaining in place to signal a hidden or otherwise unknown corrosion problem.
Each CorrView corrosion monitor is identified with its wear dimension, manufacture date, part number, serial number, and comes with a heavy duty vinyl tag suitable for recording all necessary user information, test location, and most importantly - the installation date. Each unit is manufactured entirely in the United States of 100% American components. It is quality inspected during manufacture, carefully assembled, and then finally inspected prior to shipping.
We recommend installing CorrView directly into a threadolet fitting or open port in order for it to best experience the same corrosion conditions as the pipe itself. For those 24/7 piping systems or other applications where a shutdown may not be possible or desired, CorrView should be installed at sections of pipe that can be isolated - such as at individual pumps, cooling towers, heat exchangers, or refrigeration machines.
We are pleased to mail an informative 4 fold color brochure of our CorrView corrosion monitor at request. You can also view it online at left, and download to print locally. Provides an excellent handout.
Please contact CorrView International, LLC for any further information regarding availability, application, quantity discounts, representation, resale, or custom configurations, etc. An short animated video describing its operation and benefits is provided on this site.
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P.O. Box 8513Landing, NJ 07850 www.corrview.com Ph: 973-770-7764 Fax: 973-770-6576
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