Applied

Steel Wire Rope Bending Cycle fatigue

Part Four-Practical example of Bending fatigue Calculator Hardware

The series titled  Wire Rope Integrity Management is to be read in conjunction with the Whole Life management of Steel Wire ropes procedure  and consists of the following elements:

Part One – Bending Cycle Counting

Part Two – Initial Setting of Trigger Action and Trigger Discard Values

Part Three –  Empirical assessment of Steel Wire Rope Service Life using Bending fatigue Calculation

Part Four – Practical example of Bending fatigue Calculator Hardware

Part Five -  Structural Fatigue Cycle Counting


The following describes a hardware solution provided to a Well Intervention System which had Wire Rope Cycle fatigue issues

Deliverables

Technical Description

This should include but not be restricted descriptions pertaining to:

Philosophies;

Architecture;

Security of Connection to existing system;

Software and Firmware Details and Control Management.

Technical Library.

The FMS should be supplied with technical literature allowing for the identification of salient parts, basic level functionality and  fault finding.


For supplier proprietary parts or software exist then a suitable alternative may be provided.



EMC Compliance

Equipment installed and Installation shall be compliance with the following standards:

EN 60945:2002 – Maritime Navigation and Radio communication equipment and systems- (General requirements and methods of testing and required test results)

EC 60533:1999 – Electrical and electronic installations in ships – electromagnetic compatibility



Functionality

The FMS shall be capable of retrieving in a non-intrusive way such data to comply with the requirements for  Section 9  Records Kept from existing  Well Intervention Control system without modification


This information shall be manipulated, through multipliers,  in accordance with  Appendix A but without the Manual Intervention described.



Software Versions

Software shall be developed to display information on a simplistic way on the vessel and allow necessary interaction with system parameters.

Extended software shall be developed for onshore to allow for system modelling through variation of parameters against historical data.

The system shall display modified data on a GUI in simple line graph format.


Architecture

Final Architecture is to reflect the functionality of the following as  described


A HMI/PLC shall be proved with requisite software installed. This should connect into the existing Well Intervention System SCADA system in a non intrusive way via a Layer 3 Switch to allow for pulling of data from Local bulk storage devices to  Onshore Network system ( this functionality shall be provided by  Company IT)

The following peripheral devices shall be provided for:

Local Printer;

Local Bulk storage device, with hot swappable, zero install impact capability;


The system should be so designed so as to be portable to other vessels


1.1 Hardware

Hardware shall be selected for which there is known continuation of support and upgrade path with a view to service life of not less than 20 years.


Hardware should be suitable for operation in a marine environment. Power supply shall be declared and be 24v DC or 220v AC single phase 60 Hz.


Note that AC supplies may be susceptible to limited  frequency and voltage fluctuation.



Physical Connection

The Well Intervention Control System utilises a Siemens S7 PLC as the main control point for the system. In order for the FMS to function, it is necessary to connect to this Siemens S7 in order to retrieve real time status information for the crane system.


In order to avoid invalidating any warranty with the CCS, it was necessary to develop a connection that would not require any changes to the S7 PLC software or hardware configuration.



The connection between the two systems is achieved by using a BHSoftec IBH Link S7 to Ethernet adapter. This converter features a 9 pin serial connector, which is connected directly to the MPI port on the Siemens S7 PLC.

The converter is then connected to the FMS via an Ethernet cable, where a proprietary driver is used to allow communications with the S7 PLC.

This allows a physical connection to be established between the CCS and FMS, without changing the configuration of the CCS. Additionally, the connection can be removed at any point by simply unplugging the Serial connector from the CCS.

As Ethernet is being used to connect to the S7 PLC, it is essential that the system must remain on its own closed network, in order to prevent unauthorised access to the crane control system. To facilitate this, the FMS system will contain its own network switch, located within the locked cabinet. No additional systems may be connected to this system.


1.0 Software Connection

In order to reduce traffic and load on the Siemens S7 PLC, rather than requesting each individual data point that is required, the data will be requested in blocks covering the required registers. The following data blocks will be retrieved:

Database          Offset                 Buffer Size

421                   232                     8

430                   228                     8

1130                    68                   16

1330                   28                    100

1430                   44                    204


These blocks will be read once every second, in order to minimise impact on the CCS.

Once the data block has been retrieved, the following values of relevance can be retrieved from the block:

S7 DB Address       S7 Data Point Name                                               Beckhoff Data Point Name

430 : 228              HeaveAverageHeave                                        rSignificantWaveHeight

   

421 : 232              HEAVERollAngleMovAvTime                                rHeaveRoll

421 : 236              HEAVEPitchAngleMovAvTime                              rHeavePitch

   

1130 : 68              Mwhloadcell                                                  rMainWinchLoad

1130 : 80              Mwhwirelengthabsolute                                   rMainWinchDeployedDepth

   

1330 : 28              PodFwdLoadcell                                             rPodwireFwdLoad

1330 : 52              PodFwdAbsWirelength                                    rPodwireFwdDeployedDepth

1330 : 100             PodAftLoadcell                                             rPodwireAftLoad

1330 : 124              PodAftAbsWirelength                                    rPodwireAftDeployedDepth

   

1430 : 44              GuiFwdPsAbsLength                                     rGuidewireFwdPortDeployedDepth

1430 : 52              GuiFwdPsApproxLoad                                      rGuidewireFwdPortLoad

1430 : 108            GuiFwdSbAbsLength                                   rGuidewireFwdStbdDeployedDepth

1430 : 116            GuiFwdSbApproxLoad                                      rGuidewireFwdStbdLoad

1430 : 172            GuiAftPsAbsLength                                             rGuidewireAftPortDeployedDepth

1430 : 180            GuiAftPsApproxLoad                                          rGuidewireAftPortLoad

1430 : 236            GuiAftSbAbsLength                                         rGuidewireAftStbdDeployedDepth

1430 : 244            GuiAftSbApproxLoad                                         rGuidewireAftStbdLoad

   


While the data link between the S7 PLC and the Beckhoff PLC supports both read and write operations, only read functionality will be implemented in the Beckhoff PLC, in order to reduce the risk of unintentional movements of the crane.


Security

All Firmware and Software shall be password protected and restricted.HMI shall be provided with permission levels accessed through security log in. Screensaver mode  requiring login after 30 Minutes inactivity


User

Able to view current installed wire ropes only

Able to answer Alerts


Manager

Able to view installed and archived wire ropes

Able to install and Archive Wire ropes

Able to perform cutbacks

Able to set and reset Wire Rope length


 Systems Manager

Able to view installed and archived wire ropes

Able to install and Archive Wire ropes

Able to perform cutbacks

Able to set and reset Wire Rope length

Able to set and reset User Defined maximum

Able to Set and Reset multipliers


Additional Permissions

An additional layer of access  shall be provided by suitable means for Service Technicians


Alerts

Visual/Audio demonstration shall be allowed at Local HMI for the following Alerts .

Unique ID in Use

Wire rope approaching User Defined Maximum  ( 90% UDM)

Wire Rope exceeded User  defined Maximum (100% UDM).


A volt free NO contact shall be provided for future activated by Alert.


When in ‘screensaver’ mode Alerts are to be clearly demonstrated


Records Kept

Each wire rope Shall be assigned a User definable identifier. A wire rope may be either Installed, or  Archived (Uninstalled)


The FMS shall record a history of usage  for each Wire rope either Installed or  Archived which shall include the following

Bending Cycles/ Load   as raw data as  minimum 5 second Snapshots.

History of Cutbacks

A record of Multipliers in use at time of data recording

These records are to be so kept to allow User to retrieve such information  as required to demonstrate that proper management of the wire rope has occurred including pre and post cut back status during the rope life cycle


Format

Data shall be stored in a recognised data format accessible without special interpretation. Recommended format is CSV


As Built example

System on FAT before installation 2012

Testing and Installation

EMC

Equipment installed and Installation shall be compliance with the following standards:

EN 60945:2002 – Maritime Navigation and Radio communication equipment and systems- (General requirements and methods of testing and required test results)

EC 60533:1999 – Electrical and electronic installations in ships – electromagnetic compatibility


FAT

Before distribution to the vessel an FAT is to be carried out to demonstrate the main system functionality to a Helix Well Ops UK representative


Set Up and  SAT


APD are to supply for review  a Set Up procedure and Site Acceptance Test.  This shall include a number of test protocols to demonstrate correct functioning.


Instruction and Training

APD shall before a help file either as hard or software. APD are to consider and agree with Helix well Ops Uk  required training for operation of the system at various described permission levels



Maintenance

The unit does not have any user maintainable  parts, maintenance should be restricted to a periodic  Close Up inspection of component parts for signs of defect


Spares

A spare shall be carried for each major component