First of two rail track monitoring systems commissioned on Dubai Metro

Strainstall Operations have recently completed the commissioning of a rail track monitoring system for damaged wheel detection on the Dubai Metro.  Currently under construction, the Dubai Metro is a driverless fully automated metro network which will run underground in the city centre and on elevated viaducts elsewhere.  When completed it will be the longest fully automated rail system in the world.  Due to a rapidly growing population and severe traffic congestion, the metro is needed to provide additional public transportation capacity and to relieve motor traffic.  It is predicted that it will ultimately carry over 1 million people on an average day.

Strainstall Operations were contracted to supply two Wheel Impact Load Detection systems (WILD) for the Red and Green Lines.  The primary purpose of the WILD system is to detect wheel flats, as they cause serious damage to both rail vehicles and track and can even be a cause of derailments.  The costs associated with replacing track and undertaking train repairs can easily be avoided by installing a WILD monitoring system.  Sensors are mounted directly onto the rails and each time a train passes the system records data.  Any wheel that generates a force that is above a pre-defined threshold causes alarms to be triggered and a report identifies the particular wheel that needs further investigation.  This information is sent to the Line Supervisor who can then decide to remove a particular train from service or reduce its speed.  The data can also be used to give warning of potential damage to track or rolling stock and to aid decision making on operational restrictions and remedial action.

The first system has been installed on the Red Line which opened in September and runs from the airport to Jebel Ali.  The second system is due to be installed on the Green Line in February 2010.  Strainstall Operations sent out a team of five engineers over a five week period to complete the installation and to carry out the commissioning and training.  An engineer from Strainstall Middle East also attended the training sessions as they will be responsible for maintaining the system during the warranty period.

Strainstall Middle East supply Module Weighing System to NPCC

The National Petroleum Construction Company (NPCC) in Abu Dhabi specialise in the fabrication of steel structures for the onshore and offshore oil & gas production industry.  Strainstall Middle East LLC have recently supplied them with 44 compression load cells which will form the basis of a computerised weighing system to weigh and calculate the centre of gravity of large offshore oil rigs, jack-up rigs and vessels.

Designed to measure a maximum load of 16,000 tonnes, this new weighing system comprises of fourteen 500 tonne and thirty 300 tonne capacity load cells along with custom designed software to read and display individual load cell readings, total loads and the centre of gravity of the module being weighed.  Each lifting point can have a maximum of eight load cells and a minimum of two, the number being determined by the size of the structure (although they must always be even in number).  NPCC personnel were trained to operate the system and the first lift of 2,500 tonnes was successfully carried out in mid June under the supervision of Strainstall Middle East, and a much larger 13,000 tonne lift was completed in July.

The system will facilitate the safe lifting and transportation of these extremely large and heavy structures by enabling the lifting operators to determine the dead weight and therefore the type of crane required, as well as the centre of gravity to establish the best position of the lifting points to keep the structure stable during a lift.

This is the first big order for the new stainless steel Type 7510 compression load cells designed and manufactured by Strainstall Marine at Cowes.

DockAlert system for Zeebrugge LNG terminal delivered and commissioned

Strainstall Marine have recently delivered and installed a DockAlert system at Fluxys Zeebrugge LNG terminal, which is an extension to a mooring system supplied around 4 years ago.  The terminal has been able to receive larger LNG vessels since the summer of 2008 and since then several Q-Flex ships, which have a capacity of up to 217,000 cubic metres of LNG, have docked in Zeebrugge.  These new 'super sized' tankers present an increased risk of causing damage to the terminal's infrastructure, particularly during intricate docking operations.  To help minimise the chances of such an incident occurring, Fluxys installed a DockAlert vessel approach system to help control the speed of impact of the vessels onto the fenders.

Two lasers were installed on either side of the jetty head to measure the distance of an incoming vessel's bow and stern relative to the jetty, while also providing it's speed and relative angle to the berth.  The data from these lasers is fed into a central control system where it is displayed in the jetty control room and relayed to a large digit display mounted on the jetty.  The large digit display is visible from 300m and provides the pilot with information on the speed of approach and distance from the jetty.  This ensures that the approach speed is kept within the allowable limits for the jetty's safe operation and once the vessel is safely moored, DockAlert then monitors any drift-off of the vessel to protect the loading arms and provides warnings to the operators.  The installation and commissioning went very smoothly with positive feedback received from the customer.

Strainstall Marine has also received an order for another DockAlert system for an oil storage terminal in Shenzhen, South China.  Brightoil, the terminal opertaors, are also planning to purchase another 4 systems over the next two years for other terminals in the region.

Automated monitoring equipment installed at Blackfriars

As part of Blackfriars Station reconstruction, Strainstall Operations have now completed the installation of automated monitoring equipment on the underground Waterloo and City Lines and District and Circle line station area, where demolition works around Blackfriars station above the ground are currently underway.

The system comprises hundreds of prismatic targets fixed to the track and tunnel linings with robotic total stations that scan the prisms looking for any distortions to the track and linings caused by the construction and foundation works.  Several buildings adjacent to the construction site are also being monitored and include the Blackfriars Pub (a listed building) and offices attached to the station.

The demolition of the surrounding structures causes the ground to move, initially heaving and eventually settling down again when new buildings have been constructed.  This ground movement can cause damage to nearby buildings and effect the underground tunnels and railway tracks by reducing the gap (clearance) between the trains and the tunnel linings - an unsafe condition.  The monitoring systems supplied by Strainstall Operations constantly check for any such changes and will alert the project management team to any potential problems so that remedial action can be taken.

Strainstall's test machine passes recalibration with flying colours

The large Strainstall designed test machine at Cowes has been recalibrated by NPL (National Physical Laboratory).  It was first calibrated when new, in December 2006, when it achieved excellent results, with a 0.5 Grade (0.5% of reading) in the range of 1,200 tonnes down to 300 tonnes to BS EN ISO 7500-1:2004.  Since that time it has worked hard without problem, initially on the Shenzi TLP load cells where almost the full capacity of the machine was used for proof loading at 1701 tonnes.

To provide the recalibration, NPL needed a reference load cell calibrated to the necessary standards and this was done at the German National test house.

The outcome has been a great success.  The test machine load monitoring system required no adjustment at all and the grading results matched those achieved in the original calibration.  The numerical results were slightly better than last time.

Second Potshell instrumented at Dubai Aluminium

Based in Jebel Ali, Dubai Aluminium (DUBAL) is the world's largest modern aluminium smelter and each year DUBAL manufactures approximately one million tonnes of finished product, made to order for 300 customers in 48 countries world-wide.  This includes foundry alloy for the automotive industry, extrusion billet for construction, transport and industrial applications and high purity aluminium for use in the manufacture of electronic components for the aerospace and electronics industries.

Aluminium smelting requires a large number of pots, which are made from high quality steel lined with carbon, in which electrolysis takes place to extract aluminium from its oxide alumina.  These pots, know as potshells, have been over designed to ensure they are safe to use and so are very expensive in comparison to DUBAL's competitors.

In order to improve the design and to reduce the amount of material and subsequent cost of manufacturing each potshell, Strainstall ME were contracted to install 26 high temperature strain gauges in different locations on a potshell to measure stresses during normal operation throughout its operational life.  These strain gauges were then connected into the existing PC system of DUBAL for data collection, further processing and analysis to determine which locations need strengthening and which do not, to facilitate the redesign process without compromising on safety.

The order follows on from a previous contract in 2008 where Strainstall ME instrumented another pot shell with 30 high temperature strain gauges, supplied the data acquisition system for data collection and assisted in the analysis of the data.

Strainstall UK supply load measuring pins for Japanese mooring load montioring system

Strainstall Marine have received an order for 48 load measuring pins, together with intrinsically safe amplifiers, zener barriers and power supply from Chubu Electric Power Company in Japan.  The company is Japan's third largest electric power company distributing power to about 10 million residential and business customers throughout central Japan's Chubu region, which includes Nagoya, one of the country's largest cities.

In response to deregulation, Chubu Electric has moved into new industries, including LNG supply and on the 7th July 2009 they started the construction of a new LNG receiving terminal at the Port of Naoetsu in Joetsu City.  The load measuring pins will form part of a load monitoring system to measure the loads in the mooring lines of LNG vessels offloading their cargo at the new LNG terminal.

The load measuring pins will be fitted into Japanese domestically manufactured quick release hooks, and the information they provide incorporated into an integrated berth management system.  This will provide the operators with clear displays of the real-time tensions in the mooring lines, an alarm facility in the event that these exceed safety limits and data recording for historic and trend informatin.

The order follows on from over 40 previous projects in Japan, where Strainstall are, to date, the only approved non-Japanese supplier of these products.

Strainstall Norway suppy winch monitoring system

Transocean are the world's largest offshore drilling contractor, providing a fleet of mobile offshore drilling units to help their clients find and develop oil and natural gas reserves.  They have recently placed an order with Strainstall AS for the supply of a new winch monitoring system which will be retrofit to an existing winch and will replace an old IP-based system.

It is now a requirement of governmental bodies and classification societies that all winches are fitted with a monitoring system that provides reliable and critical information for its safe operation including measurement of tension, line out and speed, alarms and alarm setting.

Such information is needed as operators need to know how many metres of chain they have let out so they can calculate the exact touch down position of the anchor on the sea bed.  This data is vital because of the many structures (pipelines, wellheads etc.) that are positioned on the ocean floor and, as they are unprotected, are vulnerable to damage.  If too much chain were to be lowered it could potentially drag along the sea bed and collide with any installations in the way.  If these structures were to suffer significant damage and allow leakage into the water then a serious pollution incident could occur.

The winch monitoring system minimises the risk of such an event from occurring by providing real-time data on chain length and speed when heaving in or paying out, with alarms to warn operators should the safety limits be exceeded.