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Picture for Systematic Investigation Of The Role Of Stress-Induced Pits And Grooves In SSC Four-Point Bend Testing Of Line Pipe Steel
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Systematic Investigation Of The Role Of Stress-Induced Pits And Grooves In SSC Four-Point Bend Testing Of Line Pipe Steel

Product Number: 51321-16571-SG
Author: Thomas Haase / Christoph Kalwa/ Christoph Bosch
Publication Date: 2021
$20.00
Picture for Tailoring Scale Prediction Models to a Specific Application: Reverse Osmosis
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Tailoring Scale Prediction Models to a Specific Application: Reverse Osmosis

Product Number: 51319-13238-SG
Author: Robert Ferguson
Publication Date: 2019
$20.00

Mineral scale formation is a problem across many industries and in diverse applications and equipment. Each application may have specific characteristics that must be taken into account if a modelling system is to be reasonably accurate. The modelling of cooling water and oil field production chemistry have been studied extensively since the 1970’s and state-of-the-art physical chemistry models devloped to simulate them with acceptable accuracy even under extreme conditions.Open recirculating cooling water predictive models for example must incorporate algorithms to concentrate the water treating the process as an “open” system and address cooling stem specific situations including pH control methods and even the impact of chlorination. pH prediction of the concentrated recirculating water is a key requirement.Oil and gas production chemistry modelling presents another set of unique challenges including the distribution of gasses such carbon dioxide and hydrogen sulfide between phases as a brine transitions from bottom hole conditions to the well head and then flashes at the separator. Such a system must incorporate algorithms to treat the process as a “closed” system and partition the critical gasses between phases with pressure and temperature changes and account for the impact of the sometimes dramatic environmental parameter changes upon pH solubility and physical constants.Membrane systems did not begin to receive the same rigorous treatment as oil and gas production cooling water and applications such as geothermal power production until the 1990’s. Much of the software in use by the industry relies upon simple index calculations on the level of the Langelier Saturation Index and saturation indices based upon total analytical values. The mainstream reverse osmosis application specific software generally used is not up to the rigors of high ionic strength high recovery and water reuse membrane systems. They are definitely not capable of adequately modelling cascade systems. The simple indices used for predicting scale formation and as driving forces for dosage optimization do not simulate high ionic strength activity coefficients and near as well as far effects. The simple models fail to account for speciation and the ion association of even such standard (yet critical) pairs such as CaSO4o aqueous.Scale inhibitor models in these simple models also do not account for inhibitor dissociation and the active form of the molecules. They also tend to lack the sophistication of models used in other applications which necessitate an induction time extension approach. Without adequate speciation models inhibitor solubility can not be adequately taken into account or insoluble forms controlled predictably.They also ignore in many cases application specific challenges such as membrane specific ion rejection pH prediction and control in vented (open) or tight (closed) systems and concentration polarization at the membrane water interfaceThis paper discusses the practical application of advanced physical chemistry techniques commonly employed in cooling water and oil field chemistry to application specific modelling of mineral scale formation and control in membrane systems.The techniques are discussed and applied to:· Predicting scale formation;· Identifying the upper driving force limit for inhibitors and blends;· Developing inhibitor models for minimum effective dosage; and· Developing models for preventing failure due to inhibitor solubility.The methods discussed have been validated in field applications.

Picture for TECHNICAL JUSTIFICATION OF TABLE A.23 IN NACE MR0175/ISO15156-3: THE USE OF MARTENSITIC STAINLESS ST
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TECHNICAL JUSTIFICATION OF TABLE A.23 IN NACE MR0175/ISO15156-3: THE USE OF MARTENSITIC STAINLESS ST

Product Number: 51312-01561-SG
ISBN: 01561 2012 CP
Author: Brian D. Chambers
Publication Date: 2012
$20.00
Picture for Technical Review on the Existence of Type B (Alumina) Inclusion at Hot Steel Making Process
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Technical Review on the Existence of Type B (Alumina) Inclusion at Hot Steel Making Process

Product Number: MPWT19-15601
Author: Yasser S. Al-Subhia, Mishal M. Al-Ashrahb*
Publication Date: 2019
$0.00

It is well known in the hot rolled steel making business that nonmetallic inclusions play critical
role in defining steel performance. The objective of this paper is to study laminations that were
detected via Phased Array UT system in X60MS Class-C High Frequency Welded Pipe intended for
offshore application. The linear intermittent laminations appear along the pipe and adjacent to
the weld seam from both sides at a width of 30 to 40 mm with various depths. Technical review
was carried out on 5 available pipes, pertaining to the same heat of the original pipe identified
earlier with lamination, through model experiments; both on the laboratory and on the industrial
scale. At the beginning, depth and distribution of detected laminations were analyzed by manual
UT mapping using normal beam probe. Metallurgical analysis via Energy Dispersive X-ray (EDX)
was carried out on three samples to determine the chemical composition as well as the
morphology of the lamination. The type of inclusion which turned out to be type B (Alumina-
Al2O3) inclusion was identified by evaluating EDX results using Method A per ASTM E45. As it is
a pure material based incident, failure analysis was carried out by the steel maker to identify the
associated root causes from process control prospective and the appropriate preventive
measures to avoid reoccurrence. Eventually, the applied quality control measures during
manufacturing process of HFW pipes, represented in the deployment of UT systems, were
reviewed to identify the reason behind missing such important defect before pipes are being
shipped to the client.