CWS™: Container Weight System
CWS™ seamlessly integrates SOLAS compliant load monitoring technology onto existing container handling equipment to redefine the VGM weighing process.
Adopted by the world’s leading ports and terminals, CWS™ replaces time-consuming weighbridges to provide a new, faster method of container weighing. With its real-time data output, our system automatically weighs containers during your routine stacking cycles to generate precise VGM certificates without the hassle.
CWS™ utilises our proven, highly-accurate load monitoring pins and diaphragm load cells to provide an efficient, SOLAS compliant method for VGM processing. These are installed into the spreader, headblock, or sheaves of container stacking equipment and deliver container weighing speed increases of up to 300% when compared with weighbridges and other alternative solutions.
Maximise port efficiency
CWS™ significantly improves port efficiency by providing an integrated system that provides VGM certification as part of the container stacking cycle.
|A new revenue stream for your port/terminal
CWS™ provides a more efficient solution to VGM certification that enables terminals to charge a processing fee for the VGM verification of all containers handled without compromising output.
CWS™ has been specifically developed to achieve full compliance with the International Maritime Organisation's latest amendments to its SOLAS safety guidelines.
Why do I need a container weighing system on stacking equipment?
Weighing and validating the VGM of every laden container bound for export using a weighbridge as a means to increase revenue is just not feasible. With the timely process required to weigh the container and then re-weigh once the container is removed to offer a tare weight – any increases in revenue gained from charging for this service are quickly offset by the inefficiency caused in this lengthy process.
With its turnkey design, this faster, automated method of VGM verification Container Weighing systems for container handling equipment unlock new revenue streams that ensure swift ROI.
By using a container weighing system like CWS installed on Straddle Carriers, Reach Stackers, RTGs etc allows terminals to completely eliminate this inefficient process and instead obtain VGM data during when lifting and stacking containers in the stacking yard.
This means that terminals determine VGMs instantly, with zero compromise to efficiency and can therefore benefit from being efficient enough to weigh every container without detriment to overall output and therefore benefit from the added revenue from a chargeable VGM verification service.
By verifying the weight as a chargeable service, it then also offers the opportunity for terminals to charge a larger fee for any VGM discrepancies that will require a new VGM.
True weigh-in-motion capability
Unlike other solutions available, CWS™ can capture dynamic loads using our tried and tested in-house software. This accelerates container weighing speed by enabling the system to weigh containers while they are still in motion. This means that operators no longer need to slow down or stop their work in order to take load measurements.
With its automated weighing capability, CWS™ requires no input from the crane operator during its typical use. Integrating with your existing TOS (terminal operating system), this allows VGM verification to be completed for every container without interrupting your routine lifting/stacking operations.
CWS™ enables ports to significantly increase the number of containers that they can process.By integrating onto existing stacking equipment, weighing can be completed on multiple machines simultaneously, whereas weighbridges can only handle one container at a time. The system also reduces VGM weighing time to less than 30 seconds – down from the lengthy 10-minute processing time offered by weighbridges.
Proven track record
Having supported the world’s leading ports and OEMs, CWS™ has a proven track record in raising the bar for container weighing operations on a global scale, with over 500 systems being sold to date.
Why choose CWS™ over a weighbridge?
What machine types is CWS™ available for?
The system is available as a ‘factory fit’ option for new machines and can also be easily retrofitted into a wide range of port and terminal equipment such as reach stackers, straddle carriers, RTGs, ERTGs, rail gantry cranes (RMGs), automated stacking cranes (ASCs) and sidelifters.
Developed in partnership with the world’s leading original equipment manufacturers (OEMs), CWS™ is fully adaptable to suit all the major crane and spreader manufacturers’ equipment types. The flexible system also provides different outputs to enable integration into any existing TOS, delivering a simple, efficient, and automated method of VGM certification.
ARTGs and ASCs
Features and benefits
Strainstall's CWS™ solution has been specifically developed to meet container weight verification regulations with minimal impact to port and terminal operations.
CWS™ has successfully achieved full Automatic Weighing Instruments EU-type approval from the National Measurements and Regulatory Office.
|Accuracy exceeds industry expectations and is a fully certified system||Full compliance to SOLAS regulations|
|Weight obtained during the normal lifting cycle||No delay to port or terminal operations or compromises to efficiency|
|Retrofit solutions for all existing spreader based container handling systems||Flexible integrated solution|
|Simple to install - minimal modification required to existing equipment||Seamless process for producing VGM|
|Full TOS integration, with data output in various analogue / digital formats||Improved safety|
|Dynamic "in-motion" weighing - VGM obtained during the normal lifting and stacking cycle||Reduced installation costs resulting in minimal downtime|
|Identifies eccentrically loaded and overloaded containers||Eliminates potential for human error, no training required|
|Simple to install - no modification required to existing equipment||Highly reliable for long life and low maintenance|
|1% accuracy exceeds industry expectations for load cell based systems||Historical data available for analysis and a backup to TOS system|
|Wireless system options||Quick installation and eliminates the risk of cable damage|
|No driver intervention required - fully automatic system||High accurate VGM that meets type-approval criteria|
|Rugged proven technology - vibration and shock resistant|
|On-board data logging|
How is CWS™ installed, commissioned, and calibrated?
Strainstall’s CWS™ is designed to be retrofitted to existing container handling equipment with minimal modification required. This ensures a quick and easy installation process. Typically, two systems can be installed and commissioned per day - our engineers will install the first system and will usually supervise subsequent installations.
The system can be retrofitted into the spreader headblock or at the twistlock making it a permanent feature of the container handling equipment. This minimises wear by replacing existing load bearing pins with our strain gauged load monitoring pins, which can be integrated without our CWS interface, display and software algorithms if required.
“We assessed a number of different options to be able to offer a container weighing service to our customers and selected Strainstall’s system because it doesn’t require any changes to our port operating procedures and is quick to install. The trials demonstrated an accuracy above our expectations.”
Nick Loader, chief executive officer, DP World Southampton
Calibration and commissioning
For type-approved systems: In line with our accreditations, our expert commissioning engineers are on-hand to install, commission, and calibrate type-approved systems. Systems can also be installed by third-parties, however, these will need to be commissioned by Strainstall if they are to be EU type-approved.
For non type-approved systems: Strainstall is able to offer full installation, commissioning, and calibration training packages to enable you to install CWS™ yourself. CWS™ can also be installed by end-users or qualified technicians.
Strainstall's container weighing technical papers
Strainstall has published two technical papers outlining the pathway to container VGM compliance, clarifying the technical and commercial options available as well as presenting a cost-effective, robust and accurate solution.
While the shipper is ultimately responsible for VGM declaration, ports and terminals offer a natural environment for container VGM solutions to be implemented with packed containers already being lifted as part of normal operations.
The provision of this service by ports and terminals provides a very clear opportunity to offer an additional added value commercial service, while a failure to do so will be disruptive and costly to operations.
Download your copies of Strainstall's container weighing white papers:
Container weight verification:
Taking the load off - technology options,
Container Weight System (CWS)™ brochure
Container weighing FAQs
Strainstall has compiled a list of the key frequently asked questions relating to the implementation of the new SOLAS container weighing regulations.
The international convention for the Safety of Life at Sea (SOLAS) is an international maritime treaty to ensure the safety of the ship, the safety of workers both aboard ships and ashore, the safety of cargo and overall safety at sea. The treaty has been recently amended (chapter VI, part A, regulation 2) to require (by law) that packed containers' gross mass are verified prior to stowage aboard ship. This legislation covers all SOLAS regulated vessels, which is 98.6% of the world's tonnage.
The IMO's SOLAS amendments provide two approved methods in determining the container weight:
- Method 1 - weighing the loaded container
- Method 2 - weighing the contents of the container and adding those weights to the containers tare weight
If the new regulation is clear, at least in principle, on what needs to be done to achieve compliance, it is also unambiguous on who is ultimately responsible: Container VGM determination can be subcontracted to a third party by the shipper, but the shipper remains responsible for regulatory compliance.
Under the SOLAS requirements, the shipper named on the ocean bill of lading is the party responsible for providing the maritime (ocean) carrier (master) and the terminal operator (terminal representative) with the verified gross mass of a packed container. The carrier and the terminal operator must not load a packed container aboard a ship unless they have the verified gross mass for that container.
Due to the complexity of the international supply chain, the entity identified as the shipper on the bill of lading may not have direct or physical control over key elements of the process by which verified gross mass is determined. A shipper in such circumstances should be aware of their responsibilities and ensure that arrangements are in place to obtain and provide a verified gross mass in compliance with these international and national regulations.
Download Strainstall's 2016 container weight verification technical paper (5.5MB) to learn more.
SOLAS does not instruct any particular form for communicating the verified gross mass of a container. The VGM information must be signed and dated by the shipper or a person duly authorised by the shipper. Signatures may consist of the last name of the responsible person in capital letters and can be exchanged electronically.
As an international issue, SOLAS regulations state that VGM weighing equipment, for both method one and two solutions, must meet national certification and calibration requirements. There is no provision in SOLAS for any margin of error.
Shippers using compliant weighing equipment and procedures will obtain VGM values that are well within any national tolerances adopted for enforcement purposes.
The new ruling will be officially enforced by the maritime authorities of individual nations, whose implementing regulations will vary depending on country and region. The real-world enforcement seems most likely to be carried out directly by the container lines and terminal operators, who are obligated not to load a container without the certified VGM document accompanying it. National enforcement agencies may implement measures to satisfy themselves that compliance is achieved, which could include documentation checks, auditing or random weight checks.
Compliance with this obligation by the carrier and terminal operator may result in commercial and operational penalties, such as delayed shipment and additional costs if the shipper has not provided the verified gross mass for the packed container. As a commercial issue, penalties may involve repacking costs, administration fees for amending documents, delayed or cancelled shipments.
Although the shipper is ultimately responsible for declaring the verified weight of a container, the new amendments will affect and therefore apply to everyone within the supply chain. Shippers, freight forwarders, vessel operators and terminal operators will all need to establish procedures to ensure the implementation of the SOLAS regulatory change.
The SOLAS rules require the shipper to communicate the verified gross mass as part of an official shipping document. It must be signed by a person duly authorised by the shipper, with a first and last name, not just a company name. The signature may be an electronic signature or may be replaced by the name in capitals of the person authorised to sign it.
The VGM and signature can be part of the shipping instructions communicated via electronic data interchange (EDI), or be contained within a separate communication including a hard copy document. In either case, the document should clearly highlight that the gross mass provided is the verified gross mass.
While the onus is upon the shipper to fulfil the container weight verification obligation, the most practical location at which weighing can take place is at the ports and terminals, where lifting is a part of the existing cargo handling process.
Strainstall’s Container Weight System™ enables the weight of a container to be determined without the need to do anything different to what ports and terminals do today, the weight is obtained during the course of existing lifting operations. Spreader based weighing solutions are the only solution that have zero time and operational impact on existing terminal operations.
There is no need to implement separate lift and drop or more complex weighbridge based processes. This gives ports and terminals the opportunity to obtain a VGM for each container without any additional operational cost If a container turns up to a terminal without a verified weight it cannot be loaded onto the vessel. By installing a container weighing system on site, any potential issues of containers being stranded at the terminal need not be a worry.
The SOLAS regulations provide that verified gross mass shall be obtained under both method 1 and 2 by using weighing equipment that meets the applicable accuracy standards and requirements in the State in which the equipment is being used. Those national standards and requirements will determine the acceptable level of accuracy of the weighing equipment used.
There is no single international approval for weighing equipment to provide accurate VGM, however, all equipment used (whether for method 1or method 2) will need to meet the applicable accuracy standards and requirements of the state in which the equipment is being used.
NOTE: Strainstall's CWS™ has successfully achieved EU-type approval, ensuring full SOLAS compliance.