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The purpose of this paper is to assess the serious corrosion problems of the water injection system on the offshore oil field and to study the type, and effect factors and mechanisms of corrosion on the offshore oil field in order to develop an effective corrosion inhibitor for the sea water injection system.

The corrosion of metal in a water injection system was studied by weight‐loss and electrochemical methods.The effect factors and mechanisms of corrosion on the offshore oil field were proposed from the trend of corrosion.

FeCO₃ is the main corrosion product in the water injection system of the Chengdao Offshore Oil Field. The corrosion rate of coupons in sea water injection systems reaches a maximum peak at a temperature of 50‐60°C. The corrosion rate of coupons exposed in all three water samples increased with an increase in the dissolved oxygen concentration. When the mixed ratio of sea water and produced water and well water is 1:3:1 or 1:2:2, the corrosion rate of carbon steel is lower than is the case in pure water. The electrochemical mechanism of corrosion indicates that corrosion in the well water, produced water, and sea water samples were all controlled by the oxygen absorption process, which controlled the cathodic reaction. The corrosion rate of coupons followed the ranking order: well water; produced water; sea water.

This paper provides the main corrosion product in the water injection system of the Chengdao Offshore Oil Field, and provides new information on the effect factors and mechanisms of corrosion on the offshore oil field.

An investigation of the behaviour of a soluble resin coating on a steel substrate was carried out by open circuit potential and electrochemical techniques. Exposure conditions were with artificial sea‐water and natural sea‐water. The anticorrosion properties of the soluble resin material and its protection of the steel panel from marine corrosion were estimated by comparison with the untreated steel. The weight effect of the film coating and the temperature of the media were also studied.

The corrosion behaviour of lead and its alloys in sea‐water is of great commercial interest in view of the considerable use of submerged telecommunications cables and the growing use of lead anodes for cathodic protection of marine structures. This article is concerned with the corrosion of lead in sea‐water and saline solutions and with the anodic behaviour of lead in chloride solutions.

This paper aims to study the influence of load and environment medium on the fretting behavior of SAF 2507 SDSS.

In this study, the effect of load on the fretting behavior of SAF 2507 SDSS in air and sea water were studied. The fretting wear tests under different loads were conducted with a ball-on-flat contact configuration. The friction coefficient, wear volume, surface morphology and oxidation component were determined.

With the increase of applied load, the friction coefficient decreases both in air and sea water. The fretting mechanism is gradually transformed from partial slip regime to slip regime in air while the fretting counterparts are all in the state of gross slip in sea water. In sea water, the friction coefficient is lower while the wear loss is higher compared with that in air.

This research suggests that the fretting behavior of SAF 2507 SDSS is related to load and environment medium.

The results may help us to choose the appropriate load under different environments.

The main originality of the research is to reveal the fretting behavior of SAF 2507 SDSS under different loads in air and sea water, which would help us to realize fretting behavior of SAF 2507 SDSS is controlled by the combination of applied load and lubricating environment.

The peer review history for this article is available at: http://dx.doi.org/10.1108/ILT-08-2019-0335.

The basic aspects and mechanism of corrosion of steel piles in sea water are briefly discussed. The effects of parameters viz. pH, salinity, dissolved oxygen, temperature and wind velocity responsible for the corrosion of steel piles have been presented. The methods used for corrosion control and the impressed current cathodic protection technique in particular, with its merits, when applied to under‐water marine structures are outlined. The values and importance of potential required at the surface under protection, surface current density requirement and its distribution for the protection of steel structures under different service conditions useful for the design of cathodic protection systems are presented. The characteristics of various types of anode materials with a special reference to the latest platinized (Platinum‐Niobium) niobium anodes, with their merits, over other types of anodes are tabulated. The basic considerations required for the design of cathodic protection and the design of the system have been presented.

Introduction Although nickel is generally regarded as a corrosion resistant material its resistance to sea water is only moderate. In fast flowing sea water its corrosion rate is very low; of the order of 0.0005 in/yr. Under stagnant conditions, however, it is susceptible to pitting and crevice corrosion attack. Consequently, alloying has been a common method of improving corrosion resistance to obtain a material having the excellent resistance of nickel to fast flowing sea water together with an improved resistance to pitting corrosion.

Marine corrosion is one of those generic titles that many understand but very few can define. Basically it is corrosion due to sea‐water but, in fact, the worse corrosion is experienced when the sea‐water is present in the form of a mist. Any consideration of marine corrosion must, in consequence, be based on the corrosivity of sea‐water, sea‐water‐laden atmospheres, and mixtures of these.

Ocean exploration is of importance and in great demand throughout the world. This results in a huge challenge in tribology in the marine environment. Moreover, polymeric materials with large molecules or macromolecules play an important role in marine equipment.

The tribological performance of sea-water-eroded polyether polyurethane (PU) was systematically studied by using a multi-specimen test machine for different durations from 0 to 60 days. Surface characterization technologies, such as scanning electric microscopy energy dispersive spectroscopy, were used to analyze the PU samples.

It can be found that the COF measured against 316 steel increases with the testing load because of the change of contact areas for the original PU samples. The effect of hydrodynamic lubrication and heat resulted in the decline of the COF with the increase in testing speed. The COF of PU sample immersed for 20 days was the lowest compared with other samples. With the immersion time increased to 60 days, the COF increased first and then decreased. The reduced COF of PU resulted in improved anti-wear performance of the PU sample.

These results enhanced the comprehension of the tribological performances of PU immersed in sea-water.

The purpose of this paper is to investigate whether the sedimentation of calcareous deposits occurs on cathodically protected steel in Baltic sea water.

Steel electrodes were cathodically polarized in natural Baltic sea water at potential +0.150 V vs Zn electrode in potentiostatic mode. During exposure chronoamperometric measurements were carried out. After the exposure, the electrode's surface was examined by scanning atomic force microscope (AFM) and by scanning electron microscope (SEM). Deposit composition was examined by energy‐dispersive X‐ray spectroscopy (EDX). Comparative investigation was carried out in 1 percent NaCl solution (comparable to the salinity of Baltic sea water).

During cathodic polarization in Baltic sea water, non‐conducting calcareous deposits developed on steel surface. These deposits significantly lowered the cathodic current demand. Morphology and EDX spectroscopy of the deposit indicated that it was built mainly of aragonite (polymorph of CaCO3). No non‐conducting deposits on cathodically protected steel electrodes developed in 1 percent NaCl solution.

Composition of Baltic sea water favours the formation of calcareous deposits on cathodically protected steel. Sedimentation is a beneficial and desired phenomenon from the point of view of cathodic protection system of maritime construction as it facilitates polarization. Evolution of calcareous deposits should be taken into account as one of the environmental factors when designing a cathodic protection system.

This study aims to test the role of the state of occupation, represented in Israel, as one of the most significant challenges, which faces the Jordanian water security. Where Israel expands in its policy and ideology everyday its hydro-hegemony over the Jordanian waters. Hence, its acts result in negative consequences on the Jordanian water and food security, which in turn affects the Jordanian national security as a whole.

This study relied on the following two approached to tackle its problem: first: descriptive approach: the descriptive approach depends on defining the apparent features and describing their nature and the type of the relationship between its variables. It aims to achieving a better and deeper understanding on the situation of its future policies and measures. And research uses the system analysis approach to handle the subject matter. Given the influence of water on the development, Jordan, as an organic or a political and social state, takes into account the reasons and causes of development. Jordan turns into an active political state, with water as an influencing factor on it. This premise represents the core of the system analysis approach.

The research concluded that the Israeli theft of the Jordanian waters is the main factor in the Jordanian water crisis. If Jordan had received its usurped water rights by Israel, it could have been able to solve its water issue represented in the increasing deficit in its water balance. Therefore, the Israeli hydro-hegemony on the Jordanian water resources caused the imbalance in its water security and, in turn, caused the development process to falter in general.

The value of the research lies in the fact that it addresses the most important reasons behind the water crisis in Jordan, represented in the Israeli control over the Jordanian water resources and the research shows that the amount of water stolen by Israel is enough to solve the water crisis in Jordan.