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Customer focus propels Veth onward

The Naval Architect January 2021

Integrated L-drive VL550i (1)Considering    that    this    year  it    celebrates    70    years    of    involvement  with  the  maritime  sector, it’s safe to say that Veth Propulsion by Twin Disc can claim to know a thing or  two  about  marine  propulsion.  The  Papendrecht, Netherlands-based firm has grown into a global player, but it prides itself  on  remaining  true  to  its  origins  where  meeting  the  customer’s  (service)  expectations and the personal touch are key elements. 


“Besides developing new thrusters, we are doing repairs and overhauls. Nowadays it’s  only  a  small  part  of  our  company,”  explains Marco Huisman, Veth’s technical director. “We started developing products because  customers  were  asking  us.  The  man  who  founded  our  company  (Mr.  Jan  Veth)  was  able  to  think  in  terms  of  solutions  and  developed  certain  types  of bow thrusters, then in 1987 came our first rudder propeller. But we came from a service company, it’s in our DNA. We like to  try  on  the  shoes  of  the  customer  and  see what he’s going through and offer him solutions  he  would  like  to  use  and  solve  issues quickly.”


Integrated L-drive

With that customer focus comes the ability to adapt to their changing requirements, not  least  of  which  is  the  demand  for  electrical  propulsion  solutions.  In  2017,  it  launched  its  Integrated  L-drive,  an  azimuth thruster solution available with power ranging from 265kW to 2,350kW. Described  as  the  world’s  most  compact  propulsion  system,  with  extremely  low  mounting  space  requirements,  it  is  attracting interest as a solution for inland barges, tugs and superyachts. Notably, it represented  the  first  Veth  system  to  use  permanent magnet (PM) which is partly built  inside  the  thruster,  rather  than asynchronous, motors, while the absence of  gears  inside  the  ship  also  means  it  generates less noise.


Huisman explains that the development process began a few years earlier, when it started exploring the feasibility of using the smaller, lighter PM motors. He says:  “In  the  beginning  there  wasn’t  much  interest,  nobody  was  asking  for  a  super  compact thruster.  Our  innovations  are  often based on (scientific) market analysis and  the  latent  needs  of  our  customers.  Then  we  had  a  project  where  the  client  required a very compact unit and decided to take that opportunity. 


“So  we  designed  a  slightly  different  L-drive  thruster.  We  found  increasing  the  diameter  of  the  slew  ring,  which  is  for  steering,  gave  space  to  mount  the  electric motor inside the inner diameter of  this  slew  ring,  which  enabled  us  to  make  everything  much  lower  than  the  existing  L-drive  in  our  portfolio.  We  also mounted the elastic coupling partly inside  the  motor,  which  allowed  us  to  lower the motor so half of it was inside the thruster.”


PM  motors  offer  excellent  efficiency  at  full  load,  but  Huisman  says  it  is  particularly at half load that a PM motor performs  better  than  asynchronous  motors.  Nor  is  the price  of  PM  motors  such   a   deterrent;   especially   bigger   motors  (in  excess  of  1,000kW)  are  at  the  more  specialised  end  of  the  market  and  will  always  come  at  a  premium  due  to  lower  production  volumes.  The  price  of  water-cooled  asynchronous  motors and PM motors are in the same magnitude. Up to 2,000kW, in particular superyachts  and  ferries  desiring  low  noise production, there is also the option of including a contra-rotating propeller. In  collaboration  with  Promarin,  Veth’s  contra-rotating   solution   features   a   patented  asymmetric  ‘shark  tail’  design  that’s  said  to  ensure  an  optimal  flow  of  water toward the second propeller.


According to Huisman, the Integrated L-drive  is  a  “game  changer”  for  the  superyacht   market.   “Because   our   thrusters are extremely compact, it gives them  design opportunities  that  they  didn’t have before. Superyacht designers often want to include an infinity pool or beach bar, which requires some space that would  normally  be  occupied  by  engine exhaust  systems.  It’s  very  beneficial  to  them that they can use our thruster with diesel  electric  propulsion,  which  can  be  positioned  much  more  easily  than  conventional diesel propulsion with a long shaft line.”


The future

With   Veth’s   acquisition   by   power   transmission    manufacturer    and    distributor  Twin  Disc  in  2018,  Huisman  believes  there  are  now  opportunities  to  expand  the  company’s  reach.  “However,  what  we  are  finding,  from  talking  to  our partners in the United States, is that outside of western Europe many shipyards don’t  work  with  system  integrators  with  knowledge  of  diesel  electric  propulsion.  So, we need to be able to supply a complete package  with  generators,  battery  banks,  power management, frequency drives and a monitoring system. 


For the full article please see  the January 2021 edition of The Naval Architect.