Frequently Asked Questions and Their Answers
Principle & Analysis
- QWhat are the PBCF
- AAverage 5% FO Saving Effect (at
same ship speed) or
speed by 2% (at same horsepower).
- QDoes PBCF an other advantages
than energy saving?
・Reduction of torque-rich conditions.
・Reduction of stern vibration and underwater noise.
・Elimination of rudder erosion.
- QHow is the PBCF effect
- APBCF will eliminate the Hub
- QDoes PBCF effect change by the
size or type of
- APBCF will improve the propeller
efficiency and the
essentially will not depend on the size or type of the vessel.
- QDoes Slow-Steaming influence the
- AYou can expect about 5% effect on
average at any
- QIs there any negative effect for
Hull or shafting by installing
- AThere is no negative effect in
We have installed PBCF over 3,300 vessels until now and there has been no problem for Hull or
- QIn case of newbuildings, is it
necessary to change
shaft design for installation of PBCF?
- ANot at all
- QIs there any effect for
performance by PBCF?
- AThere is no effect for
reversing, circling, stopping)
- QWhy are the values of PBCF
- ASea Trial/Voyage Data on actual
interference in actual sea way, like wind, wave, sea current and there is a lot of variation in the
- QMay we ask MOL Techno-Trade to
assist in the
analysis of the
PBCF effect, after installation?
- AUpon request, we will analyze
PBCF effect and submit
Installation & maintenance
- QHow is PBCF installed?
- APBCF is fastened to propeller
boss by bolts,
comparable to the
installation of conventional propeller boss cap.
- QDoes PBCF price include
- ANo, installation fee has not
included in PBCF
Installation is the scope of the customer and usually this is included in the customer's Dry-dock
- QWhat is the installation time of
- AIt takes about 5～6 hours by 4
- QDoes your engineer attend during
- AIn case of installation on
exising vessels at
we offer a service to dispatch our supervisor for installation at our expense.
In case of other area, the additional supervising fee is neccessary.
- QWhat is the most important
regarding the PBCF
- 1) Position relation for Propeller Blade and PBCF
- 2) To use original installation materials, like fastening bolts, torque wrench.
- 3) Apply correct fastening torque to the bolts.
Installation is comparable to the installation of coventional propeller boss cap, without welding works.
- QDoes PBCF need specific
- ANo specific maintenance
PBCF may follow the propeller maintenance. For example cleaning and polishing. Further we have no
for special paint or coatings.
- QWhat drawings are necessary to
- 1) Propeller (incl. propeller particular and boss cap)
- 2) Propeller blade offset table
- 3) Propeller Shaft (shaft end and propeller nut)
- 4) Stern arrangement (showing the clearance dimension between propeller and rudder)
- 5) Rudder
- QOf which material is PBCF
- AIt is Nickel-Almi-Bronze, same as
- QCan we switch PBCF between our
- ABCF is custom made product based
Therefore, PBCF cannot be switched unless completely sister vessel.
- QAre PBCF fins removable?
- ANo. PBCF is made by using
technology, as one
- QAre there any moving parts on
- APBCF has no moving parts.
- QWhat is "PBCF"?
- AIt is an energy-saving device
- QWhat does "PBCF" mean?
- AIt is named after the initials of
"Propeller Boss Cap Fins".
- QWho (& When) invented
- AMitsui O.S.K. Lines, West Japan
Co.,Ltd and Nakashimamitsuwa Propeller Co., Ltd. (ex. Mikado Propeller) has jointly developed PBCF in
- QCan PBCF be installed only to a
- ANo, It can easily be installed on
- QDoes PBCF need Class
ANo need. PBCF is not a class approval item same as normal boss
Certain class request to submit PBCF drawing but it will be arranged by MOL Techno-Trade Ltd.
- QWhat is the Delivery time of
- AIt takes usually 3 months from
order. (Based on
Delivery in East Asia)
In case of delivery to Middle East, Europe or other area, additional over 1 month will be needed.
- QWhich types of vessel can
- AAll type of merchant vessels, and
also high speed
fishing crafts. PBCF is a propeller improver.
- QWhat is included in the PBCF
- 1) PBCF body
- 2) Accessories set (Original bolts, Calibrated Torque Wrench, Gasket, locking wire and installation
- 3) For delivery to East Asia by sea freight: transportation included (CIF at port East Asia)
- QCan PBCF be installed on a
Propeller (CPP) ?
- AYes, basically possible. However
for some propeller
type of CPP installation of PBCF is impossible.