This document discusses various deck machinery and equipment used on fishing vessels, including winches, net haulers, and other small deck machinery. It describes the purpose and function of different types of winches, including trawl winches, and how they can be powered. It also explains net haulers, net drums, power blocks, and other equipment used to haul nets and lines, such as triplex winches, transport rollers, line haulers, and fishing reels. The document provides details on how this deck machinery assists with fishing operations and is chosen based on the vessel and fishing methods used.

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19. OPERATION AND MAINTENANCE OF MECHANICAL AND
HYDRAULIC DECK EQUIPMENT
These deck machineries and deck fittings of the vessel facilitate easy handling of the
fishing gear and give a better working environment. The various deck machineries and
equipments are used for assisting the fishing operations are called auxiliary fishing gear. The
choice of deck machineries onboard a fishing vessel has a direct bearing on the fishing
operations. Following are some of the important deck machineries used onboard the fishing
vessel.
A. WINCHES
B. NET AND LINE HAULERS
C. SMALL DECK MACHINERY
WINCHES
1. Winches
2. Windlass
Winches:
Different types of winches are used for different fishing methods. They may be placed
in the fore and aft direction or athwartship, depending on the requirement. They are used
commonly in trawlers, purse seiners and Danish seiners to haul the net and the catch on to the
board.
Trawl winches can be single-drum, two-drum on one shaft or two or more drums on
parallel shafts. The last type is most suitable for double rig trawling and purse seining. A
winch may or may not have warping heads. When present, warping heads are used for
auxiliary hauling requirements such as hauling sweep lines, wings, etc. Split winches are
common in large trawlers as they enable straight lead from winch drum to gallows/gantry.
Winches can be driven either mechanically from the main engine or electrically or
hydraulically or direct drive by a separate engine. Mechanical drive is preferred in small
vessels as it is simple, reliable, easy to maintain and repair and less expensive. Electric drive
is confined to large vessels due to the necessity of a large capacity generating plant and
auxiliary diesel. However, electric winch offers good flexibility of operation and control.
Hydraulic drive is popular due to its many advantages but is used only in large
vessels. Direct diesel drive has not become popular due to problems like requirements of
more space, fuel supply and exhaust arrangements.

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Fig: POWER TAKE-OFF UNIT
Fig: WINDLASS

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Powers take-offs and winch drives:
Power take-offs unit is a clutch by which the power from the main engine is
transmitted to the winch as and when required. It has either single plate clutch or multiple
plate clutch. The power take-off unit is fitted on the front side of the engine. The power from
the engine is thus transferred to the winch through the power transmission operation. Power
transmission is carried out by either belt drive or chain drive. Belt drive is preferable to chain
drive as it has more flexibility. Hydraulic drive may prove cheaper than mechanical drive in
the long run, provided that expertise and spare parts are locally available.
Windlass:
This is a special type of winch used for handling anchor chain. The windlasses can be
driven with steam or electric or hydraulic.

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NET AND LINE HAULERS
These are used to haul the nets and lines.
1. Net haulers
2. Net drums
3. Power block
4. Triplex
5. Transport rollers
6. Tuna Line haulers
7. Main line reel
8. Line shooter (Setter)
9. Branch line hauler
10. Fishing reels
11. Gill net hauler
12. Jigging machines
13. Automatic pole and line fishing rod
14. Capstone
15. Deck bollard
Net haulers:
Net haulers are designed to suit the fishing method and popular mostly on trawlers,
gill netters and purse seiners. They may be fitted on the rails on deck or hung from a boom.
They consist of a revolving drum or sheave. Most net haulers have their sheaves or drums
rubber vulcanized to prevent wear and tear and to have a better grip. Net haulers can be
driven mechanically, electrically or hydraulically.
Net drums:
Net drums are used in gill netting, trawling and seining. They differ from net haulers
in that the entire net is wound on the drum. Most net drums are fitted at the stern. Net drums
not only reduce the labour in setting and hauling the gear but also prevent the sagging or
fouling of the gear during the operation.
Power blocks:
These were primarily meant for use in purse seining but subsequently extended to
trawling and drift netting. It is a labour-saving device. The purse seine power block is so
designed as to pass the bunched up webbing, corks and weights and rings through the sheaves
during hauling operation. It is a large self-
aluminium along with zinc. It is hydraulically driven and medium pressure hydraulics are
ideally suited for its operation.

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Fig: NET DRUMS
Fig: POWER BLOCKS

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Triplex:
It is a net winch used in purse seiners instead of power blocks for hauling large nets
with ease without damage to the webbing. It consists of three hydraulically driven rollers
fixed parallel to each other on independent shafts. Each roller has shields at the ends to guide
the net. The direction of rotation of outer rollers is the same and the middle one rotates in
opposite direction. The net passes through the top of outer drums and the bottom of the
middle one.
Transport rollers:
These are used in purse seiners to transport the net from triplex net winch to the net
bin located aft in Scandinavian purse seiners.
Tuna Line haulers:
Line haulers are used in heaving the lines. Capstan and line haulers are similar in
many respects: the former is normally slow turning used for general purpose while line hauler
(gurdy) is normally fast running and is used to haul the lines and gill nets.
Line haulers or gurdies are used in hauling the trolling lines, hand lines and jigging
lines. Most of these are hydraulically operated. Multiple reel gurdies are arranged together so
that each reel can be run independent of the other.
Tuna long line hauler consists of a lower part containing the driving shaft, a middle
part having the speed governor and the upper part consisting of three pulleys which wind the
line automatically. For the line hauler, power is supplied from main engine through
immediate shaft.
Main line reel:
The main line reel for monofilament long line is installed at stern centrally positioned
on the working deck some distance forward to the stern bulwark. The main line reel is
provided with roller assembly for releasing /storing the main line uniformly during operation.
Leader blocks are hung on the gallows at various places of working deck to guide the main
line from reel to shooting point and to the reel while hauling. The main line reel hauls the
main line with out any additional hauler.
Line shooter (setter):
The line shooter is fitted at the centre of the stern gunwale. This controls the speed of
shooting. It can pull the line off the reel faster than the speed of the Vessel. The line setter
speed by which the hooking depth can be adjusted can easily be controlled by adjusting the
hydraulic line flow controller. In practice, the hooking depth is a function of setter speed
versus vessel speed, distance between floats, float line length and branch line length.

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Branch line hauler:
Two identical branch line haulers are installed on the starboard gunwale in the
forward end of the working deck to pull the branch lines.
Fishing reels:
Reels are used in line fishing especially for single line reel fishing or single line
trolling. They can be operated either by hand, electrically or hydraulically.
Gill net hauler:
Gill net haulers are used for hauling the gill net especially on bigger vessels. They are
operated with the help of hydraulic power. These haulers are also provided with rubber
grooved rollers for hauling the nets with more grip and less damage.
Jigging machines:
Squid jigging machines are the most popular and consist of oval-shaped drums which
are arranged in pairs. They are operated manually, electrically or hydraulically. A large vessel
will have seven or eight pairs of jigging drums on each side of the vessel.
Automatic pole and line fishing rod:
This has been introduced by the Japanese and consists of hydraulically operated
swinging base on which a fishing rod is attached. It automatically lifts once the fish bites,
unhooks the fish and drops back the hook into water.
Capstone:
The single line or warp hauling needs capstone can be drive electrically or
hydraulically or mechanically.

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FIG: CAPSTONE