A method of inhibiting corrosion of metal which will be in contact with aqueous, and possibly acidic, solution comprises contacting the metal with a corrosion inhibiting composition containing more than 30% by weight of one or more organic corrosion inhibiting constituents which are water-insoluble hydrophobic material, and a corrosion inhibitor which contains one or more polymerisable groups containing double or triple bonded carbon, before contacting the metal with the aqueous solution. The method may be used to protect coiled tubing used for matrix acidizing of an oil well by propelling a slug of the corrosion inhibiting composition along the coiled tubing before pumping acid through the tubing.

A method of coating a field joint, pipe sections for forming a coated field joint, and a coated field joint formed thereby. First and second angular cut backs are provided in the parent coating of each pipe section. The first angular cut back is at an angle of about 30°±5° relative to the longitudinal axis of the field joint, and the second angular cut back is positioned further from the field joint than the first angular cut back. The first and second angular cut backs result in the parent coating having a stepped profile, a step in the stepped profile between the first and second angular cut backs, the is substantially parallel to the longitudinal axis of the field joint and is free of indentations. The field joint coating is injection moulded to have an upstand that is less than or equal to about 5 mm.

A connector for lined pipelines includes a tube having opposed male interface elements extending inwardly from respective ends of the tube. One or more circumferential permeable chokes project radially from each male interface element. The chokes minimise flow of oxidising fluid from the bore into the micro-annulus between the liner and the pipe while maximising flow of fluid from the micro-annulus into the bore in the event of catastrophic pressure drop in the bore. To maintain gaps between the tube ends and the pipe liners for fluid flow, shoulder formations extend circumferentially around the tube. The connector may be used in a joint arrangement where each liner includes a body, an end of lesser thickness and greater bore than the body that terminates short of an end of the pipe, an inner step between the body and the end, and an outer step between the end and the pipe.

Methods and systems for cleaning, coating and sealing leaks in existing pipes, in a single operation. A piping system can be cleaned in one pass by dry particulates forced and pulled by air throughout the piping system by a generator and a vacuum. Pipes can be protected from water corrosion, erosion and electrolysis, extending the life of pipes such as copper, steel, lead, brass, cast iron piping and composite materials. Coatings can be applied to pipes having diameters up to approximately 6″. Leak sealants of at least approximately 4 mils thick can cover insides of pipes, and can include novel mixtures of fillers and epoxy materials, and viscosity levels. A positive pressure can be maintained within the pipes during applications. Piping systems can be returned to service within approximately 96 hours.

An integrity monitoring system for a lined pipeline is provided for monitoring the integrity of a polymer liner in a host pipe. Methods and apparatus are described by which a lined pipeline is provided with such an integrity monitoring system. Sensor cable is able to bridge a joint between sections at lined pipe, for example by routing the sensor cable across the joint via a channel in an electrofusion fitting or by connecting successive lengths of sensor cable via pass-throughs in an electrofusion fitting. Advantageously, the sensor cable is disposed within a continuous annulus between linings and host pipes, and the continuous annulus is maintained across pipe joints using electrofusion fittings.

A multi layer pipe coating for steel pipe, and a method of production of same. The multi layer coated steel pipe has a first layer of coating, which is an anti-corrosion coating, a second layer of coating, comprising a thermoplastic selected from the group consisting of polyphenylene sulfide, polypropylene, and polystyrene, an epoxy intermediate layer between the second layer of coating and a third layer of coating, and a third layer of coating, which comprises a thermoplastic selected from the group consisting of polyphenylene sulfide, polypropylene and polystyrene. The second layer of coating and the third layer of coating comprise different thermoplastics.

A petroleum pipeline safety system for preventing contamination of an environmentally sensitive area close to a pipeline includes an upstream portion of the pipeline supplying a flow of fluid material, a crossing portion of the pipeline receiving the flow of fluid material from the upstream portion and conveying the flow of fluid material through the environmentally sensitive area to a downstream portion of the pipeline, the downstream portion, a pipeline pressure activated valve selectively capable of blocking the flow of fluid material from entering the crossing portion based upon a change in pressure within the crossing portion, and a fluid capacitor connected to the upstream portion configured to filter out a pressure spike in the upstream portion associated with the valve blocking the flow of fluid material.

Method for rotolining metallic hollow articles with metallocene-produced polyethylene.

In the coating method, a pipe for transporting oil and/or gas mined from underground is provided. An acid curable resin is passed through the pipe to adhere the acid curable resin to at least a part of an inner wall of the pipe. Then, an acid curing agent is passed through the pipe to allow the acid curing agent to make contact with the acid curable resin such that the acid curable resin is cured.

In the coating method, a pipe for transporting oil and/or gas mined from underground is provided. An acid curable resin is passed through the pipe to adhere the acid curable resin to at least a part of an inner wall of the pipe. Then, an acid curing agent is passed through the pipe to allow the acid curing agent to make contact with the acid curable resin such that the acid curable resin is cured.