CN108179423A - Auxiliary anode device and installation method suitable for ocean platform impressed current cathodic protection system - Google Patents

Abstract

Auxiliary anode device and installation method the impressed current cathodic protection system of the present invention suitable for ocean platform,Pass through the technical program,Ocean platform is as cathode,Auxiliary anode device is arranged in the ooze below sea bed face,By blowing hole operation,Place backfill,It is laid with sand pocket step and completes installation,By auxiliary anode device landfill in the scour hole in seabed,And it is stabilized in scour hole using the support spud leg and concrete anchor block of auxiliary anode device,Sand pocket covering is laid on the sea bed face for washing away hole and neighboring area to fix,It is unstable and have in the marine site of sea ice so as to effectively solve sea bed face,The installation of in-service ocean platform impressed current anode is fixed,Auxiliary anode device is effectively prevented to be destroyed by floating ice,Prevent flow,Abrasion of stormy waves and silt etc.,The difficulty of underwater operation has been simplified significantly,With higher practicability and economy.

Description

Applicable to auxiliary anode devices and safety devices in impressed current cathodic protection systems on offshore platforms installation method

technical field

The invention relates to an impressed current cathodic protection facility for an offshore platform, in particular to an auxiliary anode device and an installation method suitable for an impressed current cathodic protection system for an offshore platform.

Background technique

Regarding the installation of auxiliary anodes for impressed current cathodic protection systems on offshore platforms, the installation methods of foreign projects mainly include vertical tension anode systems, gravity anode systems and suspension anode systems.

1) The gravity anode system puts the anode on the gravity skid and on the sea mud. The disadvantage is that it is not resistant to wave action and seabed wear, and the auxiliary anode is often damaged. 2) The suspension anode system is easy to install and hangs on the In seawater, but the design life is only 5 years, and frequent replacement is required. 3) The vertical tension anode system was developed in the late 1970s, and the auxiliary anode is fixed between the deck and the seabed of the offshore platform by using a cement heavy camel , can ensure good current distribution at different water levels, it is quick to install, and can be used in water depths ranging from tens of meters to hundreds of meters.

In the existing technology, if the in-service offshore platform is to be protected, considering that the anode is not damaged by drift ice, etc., combined with the gravity anode system, there are currently three main methods.

1. Install and fix the clip: install and fix the anode on the clip of the jacket. The advantage is that the installation is relatively fixed and the cable protection is convenient. The disadvantage is that there are many underwater construction projects and tasks, and because it can only be fixed under the offshore platform, It is extremely easy to cause current shielding.

2. Pile driving method, the anode is installed and fixed on the underwater support pile. The advantage is that the anode position can be placed in a more reasonable position, and the fixation is more stable. The disadvantage is that the construction workload is large and the cost is high;

3. Concrete heavy lump: The anode is installed and fixed on the concrete heavy lump placed on the seabed. The advantage is that the construction is relatively simple and the cost is low. The disadvantage is that when the sea area is a muddy seabed, the seabed is unstable and will move due to the heavy lump. causing the cable to break.

Contents of the invention

In view of this, the main purpose of the present invention is to provide an auxiliary anode device and installation method suitable for the impressed current cathodic protection system of the offshore platform. Through this technical solution, the offshore platform is used as the cathode, and the auxiliary anode device is installed below the seabed surface In the sea mud, it effectively solves the installation and fixation of the auxiliary anode device on the offshore platform in service, especially suitable for sea areas where the seabed surface is unstable, effectively prevents the auxiliary anode device from being damaged by drift ice, etc., and prevents water flow, wind waves and The abrasion of the sediment greatly reduces the difficulty of the underwater operation, and has high practicability and economy, thereby effectively making up for the deficiencies in the prior art.

In order to achieve the above object, the technical solution of the present invention is achieved in that:

The invention relates to an installation method suitable for an auxiliary anode device in an impressed current cathodic protection system of an ocean platform, and the auxiliary anode device is installed in the sea mud below the seabed.

An installation method suitable for an auxiliary anode device in an impressed current cathodic protection system of an offshore platform is completed according to the following steps:

A. Pit blowing operation, use the workboat to blow out the scour pit on the seabed face down at the selected location according to the actual size of the auxiliary anode device;

B. Place and backfill, after hoisting the auxiliary anode device into the scour pit for placement, backfill the scour pit by backfilling sea mud or backfilling sand bags, and backfill to the same level as the seabed;

C. Laying sandbags, laying sandbags on the seabed of the Chongshabu Pit and the surrounding area for covering and fixing.

An auxiliary anode device suitable for an impressed current cathodic protection system on an offshore platform, comprising supporting legs, an anode cable, an anode, an anode rod, an anode base, and a concrete fixed pier. The upper part of the pile leg is provided with an anode fixed cross brace, and the two ends of each anode fixed cross brace are fixedly connected with the adjacent support pile legs, the upper end of the anode rod is fixedly connected with the anode, and the lower end of the anode rod is fixed with the anode base The connection, the lower part of the anode base and the anode rod and the upper structure of the supporting pile legs are poured in the concrete fixed pier, and the anode cable is reserved in the concrete fixed pier and communicated with the anode base.

As a further technical solution, the concrete fixed pier is a square trapezoidal platform, and the included angle between the four sides around the concrete fixed pier and the bottom surface of the concrete fixed pier is 60°-80°.

As a further technical solution, a glass fiber reinforced plastic shell is arranged on the outside of the concrete fixed pier.

As a further technical solution, the anode is a spherical anode.

The beneficial effect of adopting the above technical scheme is: an auxiliary anode device and installation method suitable for the impressed current cathodic protection system of the offshore platform. Through this technical scheme, the offshore platform is used as the cathode, and the auxiliary anode device is arranged below the seabed surface. In the sea mud, the auxiliary anode device is buried in the scour pit on the seabed, and is stabilized in the scour pit by using the supporting legs of the auxiliary anode and the concrete fixing pier, and sand bags are laid on the seabed of the scour pit and the surrounding area Covering and fixing, thus effectively solving the problem of the installation and fixing of the auxiliary anode of the active offshore platform in the sea area where the seabed surface is unstable and has sea ice, effectively preventing the auxiliary anode device from being damaged by drift ice, preventing water flow, wind waves and mud Sand wear, etc., greatly reduces the difficulty of underwater operations, and has high practicability and economy.

Description of drawings

Fig. 1 is the overall installation state diagram of the present invention.

Fig. 2 is a schematic cross-sectional structure diagram of the overall structure of the auxiliary anode in the present invention.

FIG. 3 is a schematic cross-sectional view along A-A in FIG. 2 .

In the figure, 1. Auxiliary anode device, 2 scour pit, 3 backfill sea mud or sand bag, 4 seabed surface, 5 flat sand bag, 6 supporting pile leg, 7 anode cable, 8 anode, 9 anode rod, 10 anode Base, 11 concrete fixed piers, 12 anode fixed cross braces, 13 glass fiber reinforced plastic shell, 14 backfill sand bags.

Detailed ways

The specific embodiments of the present invention will be further described in detail below in conjunction with the accompanying drawings.

As shown in FIG. 1 , the present invention relates to an installation method of an auxiliary anode suitable for an impressed current cathodic protection system of an offshore platform. The auxiliary anode 1 is installed in the sea mud below the seabed 4 .

The installation method of the auxiliary anode applicable to the impressed current cathodic protection system of the offshore platform involved in the present invention is completed according to the following steps:

A. Pit blowing operation, utilize workboat, at the place of selected position, blow out scour pit 2 downwards on seabed surface 4 according to the actual size of auxiliary anode device 1;

B. Placement and backfilling, after the auxiliary anode device 1 is hoisted into the scour pit 2 for placement, the scour pit 2 is backfilled with sea mud 3 or backfilled sand bags 14, and backfilled to the level of the seabed;

C. Lay sand bags, and lay flat sand bags 5 on the seabed surface 4 in the flush pit and the surrounding area to cover and fix them.

As shown in Fig. 2-Fig. 3, the auxiliary anode device applicable to the impressed current cathodic protection system of the offshore platform related to the present invention includes supporting pile legs 6, anode cables 7, anodes 8, anode rods 9, anode bases 10, concrete fixing Pier 11, the supporting legs 6 are three in the shape of a character, the upper part of the supporting legs 6 is provided with anode fixed cross braces 12, and the two ends of each anode fixed cross brace 12 are respectively connected to the adjacent support legs 6 Fixed connection, the upper end of the anode rod 9 is fixedly connected to the anode 8, the lower end of the anode rod 9 is fixedly connected to the anode base 10, and the lower part of the anode base 10 and the anode rod 9 and the upper structure of the supporting pile leg 6 are poured on concrete and fixed In the pier 11 , the anode cable 7 is reserved in the concrete fixed pier 11 and communicated with the anode base 10 .

As a further embodiment, the concrete fixed pier 11 is a square trapezoidal platform, and the included angle between the four sides around the concrete fixed pier 11 and the bottom surface of the concrete fixed pier 11 is 60°-80°.

As a further embodiment, a glass fiber reinforced plastic shell 13 is provided on the outside of the concrete fixed pier 11 .

As a further embodiment, the anode 8 is a spherical anode.

When the auxiliary anode of the present invention is placed in the scour pit, the supporting legs 6 of the auxiliary anode are supported on the hard position of the lower layer of the seabed, and the concrete fixed pier 11 sinks into the scour pit 2 of the seabed surface 4, and the concrete The fixed pier 11 is buried by the backfill sea mud 3. Since the bottom of the concrete fixed pier 11 is large and the top is small, the surrounding backfilled sea mud 3 is crowded on the concrete fixed pier 11, and plays the role of supporting the pile leg 1, greatly improving the overall stability. Sex, effectively prevents displacement, and the glass fiber reinforced plastic shell 13 covered by the concrete fixed pier 11 effectively isolates the erosion of the seawater in the backfilled sea mud 3 to the concrete fixed pier 11, greatly improving the working life.

In the present invention, the bottom of the supporting pile leg 6 can be made into a pointed shape so as to be inserted into the sea mud below the scour pit 2 .

The above descriptions are only preferred feasible embodiments of the present invention, and are not intended to limit the scope of the present invention.

Claims (6)

1. the installation method of auxiliary anode device, feature exist a kind of impressed current cathodic protection system suitable for ocean platform In the auxiliary anode device is mounted in the ooze below sea bed face.

2. according to the installation of auxiliary anode device the impressed current cathodic protection system described in claim 1 suitable for ocean platform Method, which is characterized in that complete according to the following steps：

A. blow hole operation, using operation ship, in the place of selected location, by auxiliary anode device actual size seabed towards Lower blowout scour hole；

B. place backfill, auxiliary anode device is lifted into placed in scour hole after, to scour hole by backfill ooze or return Back-up sand bag is backfilled, and is backfilling into equal with sea bed face；

C. sand pocket is laid with, sand pocket is laid on hole and neighboring area sea bed face is washed away and carries out covering fixation.

3. one kind auxiliary anode device suitable for ocean platform impressed current cathodic protection system, which is characterized in that including branch Spud leg, anode cable, anode, anode rod, anode pedestal, concrete anchor block are supportted, the support spud leg is in isosceles triangle for three Layout, support spud leg top are provided with anode and fix stull, each anode fix the both ends of stull respectively with adjacent support stake Leg is mutually fixedly connected, and the anode rod upper end is fixedly connected with anode, and anode rod lower end is fixedly connected with anode pedestal, anode pedestal and The lower part of anode rod and the superstructure of support spud leg are cast in concrete anchor block, and anode cable is reserved in concrete and consolidates Determine in pier, and be connected with anode pedestal.

4. auxiliary anode device the impressed current cathodic protection system according to claim 3 suitable for ocean platform, It is characterized in that, the concrete anchor block is square bucking ladder, is fixed on four sides with concrete around the concrete anchor block Angle between pier bottom face is 60 ° -80 °.

5. auxiliary anode device the impressed current cathodic protection system according to claim 3 or 4 suitable for ocean platform, It is characterized in that, it is provided with glass fibre reinforced plastics casing on the outside of the concrete anchor block.

6. auxiliary anode device the impressed current cathodic protection system according to claim 3 suitable for ocean platform, It is characterized in that, the anode is ball anode.