The test loads for maritime lifting appliances and pulling accessories

   

The text below is just a brief review of the test loads for maritime lifting appliances. 

The text provides as well a possibility to differentiate among lifting appliances and pulling accessories.  

Disclaimer:

This text represents only the author personal opinion about the engineering topics presented. This personal opinion is not comprehensive and definitive and it is rather an invitation for discussions, comments and feedback and shall be considered accordingly.

The author can’ take any responsibility for any type of use of this text. 

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Legislation


The basic regulatory requirements of maritime lifting appliances are governed by International Labour Organisation (ILO, UNO agency) Convention 152 (C152) Occupational Safety and Health (Dock Work) [1]. This convention was adopted in1979 but its roots go back to 1932 when Protection against Accidents (Dockers) Convention 32 was adopted. 

The convention is the base for the ILO code of practice Safety and health in ports. The actual revision of code is 2005 [3] but ILO has published in 2016 the draft of a new revision ([4] and [5]).


The code explicitly [1].1.2.1:

“covers all aspects of work in ports where goods or passengers are loaded onto or unloaded from ships, including work incidental to such loading or unloading activities in the port area. It is not limited to international trade and is equally applicable to domestic operations, including those on inland waterways.”


The application of code for offshore lifting operations is not mandatory and only recommended [1].1.2.6: 

“It is necessary to take special additional precautions in connection with the loading and unloading of goods onto or from ships at offshore oil installations. These are beyond the direct scope of this code, but much of the guidance contained in it will be relevant to such operations.”


However, the text of convention [1] specifies:

“Article 1:

For the purpose of this Convention, the term dock work covers all and any part of the work of loading or unloading any ship as well as any work incidental thereto; the definition of such work shall be established by national law or practice. The organisations of employers and workers concerned shall be consulted on or otherwise participate in the establishment and revision of this definition.”


Many national authorities have extended the application of the requirements from dockside to offshore as well.

The test load values provided in Appendix D of [3] are the basic values for the load testing of all lifting appliances installed on board. 


These test load values as well the records of all load tests are listed on the “Register of lifting appliances and Items of loose gear” [6] mandatory to exist on board. 


  

[1] ILO C152 - Occupational Safety and Health (Dock Work) Convention, 1979 (No. 152)

http://www.ilo.org/dyn/normlex/en/f?p=NORMLEXPUB:12100:0::NO::P12100_ILO_CODE:C152

[2] ILO C032 - Protection against Accidents (Dockers) Convention (Revised), 1932 (No. 32)

http://www.ilo.org/dyn/normlex/en/f?p=NORMLEXPUB:12100:0::NO:12100:P12100_ILO_CODE:C032

[3] ILO code of practice Safety and health in ports

http://www.ilo.org/safework/info/standards-and-instruments/codes/WCMS_107615/lang--ja/index.htm

[4] The inspection of occupational safety and health in ports: a review of existing guidance and practice

http://www.ilo.org/sector/Resources/publications/WCMS_161219/lang--en/index.htm

[5] Draft revised code of practice on safety and health in ports

http://www.ilo.org/sector/activities/sectoral-meetings/WCMS_533394/lang--ja/index.htm

[6] Register of lifting appliances and Items of loose gear

http://www.ilo.org/global/standards/subjects-covered-by-international-labour-standards/dock-workers/WCMS_213929/lang--en/index.htm

Open sea lift – Increased dynamic

  

The open sea lift is characterised by increased dynamic in comparison with port or harbour or even sheltered waters lifts.


The increased dynamic is the result of the movement of ship under the effect of wind and waves.


If the load is lifted or lowered through and in water, more dynamic is added. 


In order to consider this increase in dynamic, some codes (e.g. [7]) ask that the minimum test load to be estimated based on the same formulae in [3] but considering a “reference SWL” what represent the actual SWL amended for a higher dynamic.


Note:

In [7], if the dynamic factor (DF) is greater than 1.33, the reference SWL for estimating the test load is 0.75*DF*SWL.


  

[7] DNVGL-ST-0378 “Standard for offshore and platform lifting appliances”

Open sea lift – ROV Launch And Recovery System (ROV LARS)

  

The ROV LARS could be anything from an ad-hoc arrangement composed from a rigid A-Frame with sheave and one winch (on same grillage or separate on deck) to sophisticated equipment – e.g. pivoting frame actuated by cylinders, with telescopic arms and eventually with a head combining an aligner with a secondary winch. 


The ROV is launched and recovered through the splash zone and sometime to great depths therefore the dynamic during lifting and lowering of ROV could be significant and could vary a lot between the phases of the operation.


Dynamic amplification factors as 2 or 3 are normal therefore the regular testing of ROV LARS to account such values of dynamic factor may be difficult and eventually could result in damaging sensitive elements of the ROV line.

 

The common industrial practice is to test the equipment with load values accounting high dynamic after manufacturing or after any significant intervention into equipment, or periodically (every 5 years) for the permanently installed ROV LARS.


For the temporary arrangements or for annual or un-scheduled tests of permanent arrangements, the industry tends using the recommendation of International Marine Contractors Associations (IMCA) [8]. 

IMCA recommends load testing the ROV LARS with 1.5*SWL.

Definitively the load test with 1.5*SWL complies with requirements in [3] but doesn’t satisfy the test load value resulted from dynamic factor correction. 


The parties responsible for the safe installation and operation of ROV LARS are responsible to decide what value of test load from the three options below

· ILO code of practice Safety and health in ports [3];

· IMCA’s 1.5*SWL [8]; or

· ILO code of practice Safety and health in ports [3] applied for reference SWL

satisfies better the safety needs of the installation and/or operation.


  

[8] IMCA LR 010 / IMCA R 021

Open sea lift – Equipment for pipeline and cable offshore operations

  

Traditionally the equipment for pipeline and cable offshore operations are considered lifting appliances. 


However there are few significant differences between these equipment and the traditional lifting appliances:

a) The pipeline or the cable line is a continuous object and not a discreet object what is lifted or lowered;

b) Due to the continuous nature of line the clear identification of SWL (and in consequence dynamic factor) is very difficult (practically not possible);

c) Pipeline and cable operations have much longer duration than any open sea lift or lowering;

d) Pipeline and cable operation are in-depth engineered non-routine or semi-routine marine operations.


The difference between lifting/lowering a discreet load and lifting/lowering something continuous is made explicit by UK’s LOLER [9] Approved Code of Practice and guidance [10].

The guidance 32.a of Regulation 2 states that: 

“Other examples of equipment and operations not covered by LOLER include: 

(a) a conveyor belt; … ”


Considering the above it is importing identifying the characteristic loads indicated by manufacturer for equipment, eventually what are the test load values and procedures indicated by manufacturer of equipment.


For example, if the manufacturer indicates as characteristic loads for equipment SWL and DF, the test load values could follow [3].

If the manufacturer indicates as characteristic load for equipment the design load or the maximum dynamic load (DL, normally equivalent with SWL*DF), test load values as 1.1*DL (for small loads) or DL should be sufficient to satisfy [3].


However, taking into account that the operation is engineered in-depth (e.g. depends on strict weather window), the maximum characteristic load of the equipment might not be reached during operation and lower reference load may be possible to be used for load testing.


The parties responsible for the safety of the operation are responsible to decide what value of the test load satisfies better the safety needs of the operation.


  

[9] http://www.hse.gov.uk/work-equipment-machinery/loler.htm

[10] Safe use of lifting equipment, Lifting Operations and Lifting Equipment Regulations 1998. Approved Code of Practice and guidance

http://www.hse.gov.uk/pubns/books/l113.htm

Open sea lift – Personnel

  

Life Saving Appliances

The equipment for life saving don’t fall under the same load testing requirements as the regular lifting equipment. These equipment are subject to special SOLAS requirements (LSA Code). 


Lifting of personnel in air

The lifting appliances what could lift/lower people are subject to special requirements.

In general the load test for the SWL on equipment plate is sufficient because the SWL applicable for lifting personnel in air is at least two times smaller than the SWL for cargo lifts. 


Diving

The equipment for life saving doesn’t fall under the same load testing requirements as requested in [3] for the regular cargo lifting equipment. 

The dynamic amplification factor is expected to be minimum 2.2 (and involves special precautions). The test load value has to consider the effect of increased dynamic. 


The parties responsible for the safety of these operations are responsible to decide the load tests satisfying the regulatory requirements.

Why should lifting appliances be differentiate the from the pulling accessories?

  

The lifting and pulling (or winching) should be observed as two distinct operations differentiated at a very basic level by the risk involved in operation.


Lifting operation involves change of level and/or suspension therefore the main risk associated with the operation is the falling of object lifted or suspended under the effect of gravity.


Pulling operation involves change of position on a horizontal surface what provides support for gravitation effect therefore the main risk associated with this operation results from the eventual sliding of the object pulled.


This difference is made explicit by UK’s LOLER [9] Approved Code of Practice and guidance [10].

The guidance 32.b of Regulation 2 states that:

“Other examples of equipment and operations not covered by LOLER include: 

b) winching a load where the load does not leave the ground;…”


Note:

Same winch could be integrated either in lifting arrangements or pulling arrangements – e.g. as part of a launching and recovery system for an observation ROV or as tugger winch for stabilising the pendulum oscillations of a subsea template.


The function of the arrangement incorporating the equipment will define the actual type of equipment.  

It has to be noted that the differentiation above is done based only considering the risk of load falling free. Other intrinsic aspects of offshore operation involving lifting appliances or pulling accessories may raise equally significant risks to the health and safety of operation and personnel.


The actual risks of a specific operation shall be identified and analysed by an appropriate risk assessment process.

  

Considering that pulling is not the same as lifting, the test load values requested by the lifting appliances codes occur as not mandatory for the load test of the pulling accessories. However, if no other values are requested by other applicable regulatory regime or on base of contractual requirements, the test loads in lifting appliances codes could be a reasonable option. 


Example: The special case of tugger winch


People ask permanently if the tugger winch shall be load tested after installation on board.


The tugger winch is not lifting a load but controls the horizontal movement of the load (e.g. pendulum type movement). 

The load is permanently suspended and lifted or lowered by other equipment therefore practically the tugger winch is doing a kind of winching.


From this perspective the tugger winch doesn’t fall under the requirements for testing of lifting appliances.

However, the consequences of loose of control of horizontal movement could be important or quite critical for the operation. As well, the consequences of breaking of any of the winch pulling line could be severe.


Most probable the best way to decide if the tugger winch should be load tested is a scoring method considering factors as various risks and costs for the operation.