Pipeline construction - Revision history

Designing Buildings: moved Pipelines to Pipeline construction

2020-12-15T14:43:14Z

moved Pipelines to Pipeline construction

← Older revision

Revision as of 14:43, 15 December 2020

Designing Buildings at 07:51, 7 November 2020

2020-11-07T07:51:15Z

← Older revision		Revision as of 07:51, 7 November 2020
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	* Wellpoint.		* Wellpoint.

−	[[Category:~~Water~~]] [[Category:~~Construction_techniques~~]] [[Category:~~Products_/_components~~]] [[Category:~~DCN_Product_Knowledge~~]]	+	[[Category:DCN_Definition]] [[Category:DCN_Guidance]] [[Category:DCN_Product_Knowledge]] [[Category:Water]] [[Category:Construction_techniques]] [[Category:Products_/_components]]

Designing Buildings at 08:35, 17 June 2020

2020-06-17T08:35:10Z

← Older revision		Revision as of 08:35, 17 June 2020
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	Cement lining is suitable for pipes carrying potable water, oil refinery cooling water, salt water and fire water mains.		Cement lining is suitable for pipes carrying potable water, oil refinery cooling water, salt water and fire water mains.

−	~~= Find out more =~~	+	= Related articles on Designing Buildings Wiki =
−		+
−	=== Related articles on Designing Buildings Wiki ===	+

	* Drainage.		* Drainage.
	* Mains gas.		* Mains gas.
	* Manhole.		* Manhole.
		+	* National infrastructure pipeline.
	* Polyethylene.		* Polyethylene.
	* Safe working in drains and sewers.		* Safe working in drains and sewers.
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	* Wellpoint.		* Wellpoint.

−	[[Category:Water]] [[Category:Construction_techniques]] [[Category:Products_/_components]]	+	[[Category:Water]] [[Category:Construction_techniques]] [[Category:Products_/_components]] [[Category:DCN_Product_Knowledge]]

Designing Buildings at 14:10, 29 March 2019

2019-03-29T14:10:16Z

← Older revision		Revision as of 14:10, 29 March 2019
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	* Wellpoint.		* Wellpoint.

−	[[Category:Construction_techniques]] [[Category:Products_/_components]]	+	[[Category:Water]] [[Category:Construction_techniques]] [[Category:Products_/_components]]

Editor at 13:55, 12 June 2018

2018-06-12T13:55:29Z

← Older revision		Revision as of 13:55, 12 June 2018
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	* Mains gas.		* Mains gas.
	* Manhole.		* Manhole.
		+	* Polyethylene.
	* Safe working in drains and sewers.		* Safe working in drains and sewers.
	* Sewer construction.		* Sewer construction.

Editor at 12:40, 21 March 2018

2018-03-21T12:40:42Z

← Older revision		Revision as of 12:40, 21 March 2018
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	* Drainage.		* Drainage.
	* Mains gas.		* Mains gas.
		+	* Manhole.
	* Safe working in drains and sewers.		* Safe working in drains and sewers.
	* Sewer construction.		* Sewer construction.

Editor at 09:35, 31 August 2017

2017-08-31T09:35:42Z

← Older revision		Revision as of 09:35, 31 August 2017
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	* Vital infrastructure and redevelopment.		* Vital infrastructure and redevelopment.
	* Water transfers and interconnections.		* Water transfers and interconnections.
		+	* Wellpoint.

	[[Category:Construction_techniques]] [[Category:Products_/_components]]		[[Category:Construction_techniques]] [[Category:Products_/_components]]

Editor at 13:02, 23 August 2017

2017-08-23T13:02:00Z

← Older revision		Revision as of 13:02, 23 August 2017
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	* Drainage.		* Drainage.
		+	* Mains gas.
	* Safe working in drains and sewers.		* Safe working in drains and sewers.
	* Sewer construction.		* Sewer construction.

Designing Buildings at 13:26, 4 August 2017

2017-08-04T13:26:20Z

92.9.161.6 at 13:22, 4 August 2017

2017-08-04T13:22:29Z

← Older revision		Revision as of 13:22, 4 August 2017
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−	[[File:Pipeline.jpg]]	+	[[File:Pipeline.jpg\|link=File:Pipeline.jpg]]

	= Introduction =		= Introduction =
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	Pipelines are used to convey substances such as water, gas and sewage from one point to another.		Pipelines are used to convey substances such as water, gas and sewage from one point to another.

−	The construction of pipelines often affects large numbers of landowners, which has led to several Acts of Parliament enabling authorities and~~/or~~ bodies to construct pipelines on individuals’ land.	+	The construction of pipelines often affects large numbers of landowners, which has led to several Acts of Parliament enabling authorities and other bodies to construct pipelines on individuals’ land.

	= Materials =		= Materials =

−	~~Materials~~ used for pipelines vary with the type and purpose of pipeline. Water pipelines use the largest range of materials, including ductile iron, steel, concrete, plastic, and so on. Steel and concrete are particularly suited to large diameter pipelines extending over great distances.	+	The materials used for pipelines vary with the type and purpose of the pipeline. Water pipelines use the largest range of materials, including; ductile iron, steel, concrete, plastic, and so on. Steel and concrete are particularly suited to large diameter pipelines extending over great distances.

	The choice of material depends on several factors, including:		The choice of material depends on several factors, including:

−	* ~~Design~~ of ~~basic~~ pipeline.	+	* The design of the pipeline.
−	* ~~Ability of material to withstand internal~~ and external forces.	+	* Internal and external forces.
−	* ~~Simplicity of jointing~~ and laying.	+	* Jointing and laying techniques.
	* Durability.		* Durability.
−	* Impermeability ~~and frequency~~ of maintenance.	+	* Impermeability.
		+	* Frequency of maintenance.

	=== Ductile spun pipes ===		=== Ductile spun pipes ===
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	=== Pre-stressed concrete pipes ===		=== Pre-stressed concrete pipes ===

−	Concrete cylinder pipes are ~~comprised of a cylinder~~ made of welded sheet steel with jointing surfaces provided by sprigot and socket rings welded on to each end. The steel cylinder is centrifugally lined with concrete, after testing, followed by a winding of high tensile wire. A dense mortar coating covers the pre-stressing wires ~~to a thickness of not less than 20 mm~~.	+	Concrete cylinder pipes are typically made of welded sheet steel with jointing surfaces provided by sprigot and socket rings welded on to each end. The steel cylinder is centrifugally lined with concrete, after testing, followed by a winding of high tensile wire. A dense mortar coating covers the pre-stressing wires.

	Pre-stressed non-cylinder concrete pipes are longitudinally and circumferentially pre-stressed. The core of the pipe is formed around longitudinal pre-stressing wires. This provides the stress, when released, to the bonded concrete. In order to withstand pressure and design loads, the core is then circumferentially pre-stressed, with wires covered in protective cement mortar.		Pre-stressed non-cylinder concrete pipes are longitudinally and circumferentially pre-stressed. The core of the pipe is formed around longitudinal pre-stressing wires. This provides the stress, when released, to the bonded concrete. In order to withstand pressure and design loads, the core is then circumferentially pre-stressed, with wires covered in protective cement mortar.
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	=== Plastic pipes ===		=== Plastic pipes ===

−	Plastic pipes have the advantages of being lightweight, easy to handle, ~~good resistance~~ to abrasion and chemicals, and with low frictional flow loss. The disadvantages of plastic pipes are that they have lower tensile strength than metal pipes, and ~~are non-resistant~~ to temperature change.	+	Plastic pipes have the advantages of being lightweight, easy to handle, resistant to abrasion and chemicals, and with low frictional flow loss. The disadvantages of plastic pipes are that they have lower tensile strength than metal pipes, and have low resistance to temperature change.

	= Jointing =		= Jointing =

−	Ductile pipes are normally jointed with push-in joints. Anchored joints are used primarily for gas pipelines. Steel pipelines may be jointed by welding or more conventional methods such as ~~with~~ flanged joints, screwed joints, and proprietary joints with rubber sealing rings. Welding used where 100% line-tightness is required ~~for safety reasons~~.	+	Ductile pipes are normally jointed with push-in joints. Anchored joints are used primarily for gas pipelines. Steel pipelines may be jointed by welding or more conventional methods such as; flanged joints, screwed joints, and proprietary joints with rubber sealing rings. Welding is used where 100% line-tightness is required.

	Plastic pipelines are solvent-welded and connected by coupler and rubber rings, or with spigot and Z-socket ends.		Plastic pipelines are solvent-welded and connected by coupler and rubber rings, or with spigot and Z-socket ends.

−	Concrete pipelines are ~~jointed~~ by a flexible pipe joint comprising a gasket of rubber or synthetic material. Self-centred joints are normally filled with cement mortar or grouted using grout holes incorporated in the pipe collar.	+	Concrete pipelines are joined by a flexible pipe joint comprising a gasket of rubber or synthetic material. Self-centred joints are normally filled with cement mortar or grouted using grout holes incorporated in the pipe collar.

−	Anchorages or ‘thrust-blocks’ should be provided for all pressure mains ~~fitting~~ at bends, tees and capped-ends, so as to be able to resist the thrust from the effects of internal pressure. Unless restraints are provided joint failure will occur, since no real resistance to ‘blow-out’ is provided by flexible joints.	+	Anchorages or ‘thrust-blocks’ should be provided for all pressure mains fittings at bends, tees and capped-ends, so as to be able to resist the thrust from the effects of internal pressure. Unless restraints are provided joint failure will occur, since no real resistance to ‘blow-out’ is provided by flexible joints.

	= Construction methods =		= Construction methods =
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	=== On land ===		=== On land ===

−	Pipes ~~must~~ first be laid out along the route, in a process also known as ‘stringing’. Slings of canvas or non-abrasive material ~~should be~~ used to handle the pipes, which should not be dropped, dragged or rolled.	+	Pipes are first laid out along the route, in a process also known as ‘stringing’. Slings of canvas or non-abrasive material are used to handle the pipes, which should not be dropped, dragged or rolled.

−	Special trenching machines or hydraulic backacters are used to carry out excavation for the trenches. Joints in the pipeline may be completed before the pipes are lifted into the trench, depending on length and site location. Alternatively, the pipes are jointed once ~~the pipe has~~ been lowered into position.	+	Special trenching machines or hydraulic backacters are used to carry out excavation for the trenches. Joints in the pipeline may be completed before the pipes are lifted into the trench, depending on length and site location. Alternatively, the pipes are jointed once they have been lowered into position.

−	The trench ~~should be~~ at least 300 mm wider than the external diameter of the pipe, with additional space ~~being given~~ at each joint in order for them to be constructed in-place or inspected. Where trenches are excavated in hard or rocky ground, they should be taken deeper than the required depth and granular material used to bring them level.	+	The trench is typically at least 300 mm wider than the external diameter of the pipe, with additional space at each joint in order for them to be constructed in-place or inspected. Where trenches are excavated in hard or rocky ground, they should be taken deeper than the required depth and granular material used to bring them level.

−	~~At night, all~~ pipes should be sealed with caps to prevent ingress of small animals and other objects.	+	Temporarily open pipes should be sealed with caps to prevent ingress of small animals and other objects.

	=== Underwater ===		=== Underwater ===
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	* Pulling method: Long lengths of pipe are jointed on the shore and the completed line pulled into water by winches carried on anchorage barges.		* Pulling method: Long lengths of pipe are jointed on the shore and the completed line pulled into water by winches carried on anchorage barges.
	* Lay barge method: The pipeline is constructed and lowered to the river or sea bed from a barge. The barge is winched along the pipeline route leaving the completed line in position.		* Lay barge method: The pipeline is constructed and lowered to the river or sea bed from a barge. The barge is winched along the pipeline route leaving the completed line in position.
−	* Floating and sinking method: ~~Pipeline~~ constructed on shore, fitted with buoyancy tanks and floated ~~out to~~ position. Tanks are flooded or deflated as pipeline is lowered into position by winches on pontoons. A weight coating is used to ~~prevent~~ the natural buoyancy of the pipe.	+	* Floating and sinking method: The pipeline is constructed on shore, fitted with buoyancy tanks and floated into position. Tanks are flooded or deflated as the pipeline is lowered into position by winches on pontoons. A weight coating is used to counter the natural buoyancy of the pipe.

	= Coating and linings =		= Coating and linings =

← Older revision		Revision as of 13:26, 4 August 2017
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	= Coating and linings =		= Coating and linings =

−	~~Corrosion~~ reactions are inevitable when iron or steel is exposed to moisture. The most cost-effective method of prevention is to coat the steel ~~surface~~ with an inert substance which effectively separates the steel surface from the corrosive environment and resists the passage of electricity.	+	Corrosive reactions are inevitable when iron or steel is exposed to moisture. The most cost-effective method of prevention is to coat the steel with an inert substance which effectively separates the steel surface from the corrosive environment and resists the passage of electricity.

	=== External protection ===		=== External protection ===

−	Bituminous coatings are often used on steel pipes and are applied by dipping in a bath of molten bitumen or painting with a bituminous solution. These are suitable for mildly corrosive conditions only, and for above ground where periodic inspection and maintenance ~~painting~~ is possible. However, they do not afford lasting protection to external surfaces of pipes laid underground.	+	Bituminous coatings are often used on steel pipes and are applied by dipping in a bath of molten bitumen or painting with a bituminous solution. These are suitable for mildly corrosive conditions only, and for above ground where periodic inspection and maintenance is possible. However, they do not afford lasting protection to external surfaces of pipes laid underground.

	Other types of external protection include:		Other types of external protection include:

−	* Bitumen enamel wrapping with spiral wrap of reinforced glass tissue applied to outer surface.	+	* Bitumen enamel wrapping with a spiral wrap of reinforced glass tissue applied to the outer surface.
−	* Reinforced bitumen enamel wrapping – outer wrap has additional reinforcement in the form of a woven glass cloth.	+	* Reinforced bitumen enamel wrapping – the outer wrap has additional reinforcement in the form of a woven glass cloth.
−	* Tar enamel wrapping – inner spiral wrapping of glass tissue and outer wrap of coal-tar impregnated glass tissue ~~applied~~.	+	* Tar enamel wrapping – inner spiral wrapping of glass tissue and an outer wrap of coal-tar impregnated glass tissue.
−	* Plastic cladding (Securiclad) – ~~Seamless~~ plastic sheath of high-density polythene continuously applied.	+	* Plastic cladding (Securiclad) – a seamless plastic sheath of high-density polythene continuously applied.

	=== Internal protection ===		=== Internal protection ===

−	Bitumen lining ~~serves as~~ heavy-duty protection. After treating the pipe with primer, bitumen ~~provided in a lining of required thickness~~ is applied centrifugally, with water-spray cooling until the lining has set. Bitumen ~~in this context enables the pipe’s suitability~~ for conveyance of raw and potable waters, seawater, sewage and highly contaminated effluents. It also provides a very smooth surface with minimum flow resistance.	+	Bitumen lining provides heavy-duty protection. After treating the pipe with primer, bitumen is applied centrifugally, with water-spray cooling until the lining has set. Bitumen is suitable for the conveyance of raw and potable waters, seawater, sewage and highly-contaminated effluents. It also provides a very smooth surface with minimum flow resistance.

−	Plastic lining is produced from thermosetting epoxy-phenolic paint. It is suitable for wide variety of highly corrosive substances, including acidulated brines, seawaters, mine waters and acid solutions.	+	Plastic lining is produced from thermosetting epoxy-phenolic paint. It is suitable for a wide variety of highly-corrosive substances, including acidulated brines, seawaters, mine waters and acid solutions.

	Cement lining is suitable for pipes carrying potable water, oil refinery cooling water, salt water and fire water mains.		Cement lining is suitable for pipes carrying potable water, oil refinery cooling water, salt water and fire water mains.