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VMP-Winch Manual

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					                                   VMP-Winch Manual
                                        Sytech Research
                                      Victoria, BC, Canada
                                        1-250-656-0404

                                            Version 4.1

                                            2006-10-27




The most recent version of this document is available at
http://www.rocklandscientific.com/support.php
VMP-Winch Manual                                             Page 2 of 33




                                Caution:



ALWAYS USE CAUTION WHEN OPERATING THIS EQUIPMENT – ALL PERSONNEL
SHOULD BE FAMILIAR WITH ITS OPERATION

IMPROPER USE CAN RESULT IN DAMAGE TO EQUIPMENT AND/OR INJURY.

NEVER OPERATE THE WINCH CONTINUOUSLY AT PRESSURES HIGHER THAN 950 PSI
AS INICATED ON THE PRESSURE GAUGE.

NEVER PAY OUT THE TETHER FROM THE LAST LAYER ON THE DRUM OF THE WINCH.
THE LAST LAYER PROVIDES THE FRICTION THAT HOLDS THE CABLE TO THE WINCH.
VMP-Winch Manual                                                                                                                Page 3 of 33

Table of Contents
VMP-Winch Manual............................................................................................................................. 1
1 Shipping Contents .......................................................................................................................... 4
2 System Overview ........................................................................................................................... 5
3 Getting Started ............................................................................................................................... 7
4 System Description ........................................................................................................................ 8
  4.1    Hydraulic Pump Unit ............................................................................................................ 8
  4.2    Winch.................................................................................................................................... 9
  4.3    Line-Puller .......................................................................................................................... 10
  4.4    Hydraulic Schematic........................................................................................................... 12
5 Operation...................................................................................................................................... 13
  5.1    Winch.................................................................................................................................. 13
  5.2    Line-Puller .......................................................................................................................... 14
  5.3    Equivalent Electrical Diagrams .......................................................................................... 15
6 Purging the Hydraulic System ..................................................................................................... 18
7 Adjustments of Line-Puller Power and Speed Valves ................................................................. 20
  7.1    More notes on adjusting the line-puller .............................................................................. 22
  7.2    Slippage .............................................................................................................................. 24
8 Drum-Torque Limit...................................................................................................................... 25
  8.1    Emergency Over-ride.......................................................................................................... 25
9 Winch Controls Summary ............................................................................................................ 26
10    Electric Motor ......................................................................................................................... 27
11    Mounting the System on a Ship .............................................................................................. 28
12    Lifting the Components .......................................................................................................... 29
13    Slip-ring Installation ............................................................................................................... 30
14    Specifications.......................................................................................................................... 31
15    Illustrative Photographs .......................................................................................................... 32
VMP-Winch Manual                                                                          Page 4 of 33


1 Shipping Contents
Please check that you have received all items of the VMP-Winch System. Your shipment will
consist of:
   •   One crate containing the winch with controls, slip-rings and hydraulic couplings.
   •   One crate containing the line-puller assembly, and
   •   One crate containing the hydraulic pump coupled to an electric motor and two pairs of
       hydraulic hoses each 15 m long.
   •   One of the crates will also contain the switch for turning the electric motor on and off.
Depending on the specific options ordered, the drum of the winch may be fitted with 0 to 2500
meters of tether line for the VMP. If specifically requested, the electrically driven hydraulic motor
may not be part of the winch system (for customers who have their own source of hydraulic
pressure).

If ordered, a 10 inch diameter sheave will also be in the shipment.

The VMP-Winch is shipped dry, without hydraulic fluid in the hoses and lines.

The shipping box for the winch unit (the largest box in the shipment) is opened by removing the
wood screws on the bottom of the sides of the box. Removing these screws frees the sides so that the
tops of the boxes can be lifted off the bottom of the boxes. The winch is bolted to the bottom.

The shipping box for the pump unit (the smallest box in the shipment) is opened by removing the
top. After the top is off, remove the hoses and other items that are not bolted to the base. Then
remove the screws that the secure the sides of the box to its bottom and lift off the sides. The pump
unit can remain on the base of the shipping box.

The third box contains the line-puller. Open this box by removing the top and lift the line-puller out
of the box.
VMP-Winch Manual                                                                         Page 5 of 33


2 System Overview
The winch and line-puller system (Figure 1) was specifically designed to operate a Vertical
Microstructure Profiler such as those manufactured by Rockland Scientific International. A unique
feature of the VMP-Winch is its ability to automatically feed the VMP tether into the ocean over the
side or stern of a ship. The system consists of:
   •   a winch that is directly driven by a hydraulic motor,
   •   a line-puller that continuously feeds the tether into the water,
   •   a sheave (or block) that aligns the tether and raises it off the deck, and
   •   an electrically driven hydraulic pump that supplies hydraulic fluid to run the winch and line
       puller.
The VMP-Winch can also be powered by the ship hydraulic system if it can provide 10 gallons
(38 l) per minute at 1000 PSI (70 MPa).

Because the winch is driven directly by a hydraulic motor, the maximum torque on the drum (and,
hence, the maximum tension in the tether) is automatically limited by the hydraulic pressure at the
motor on the winch. This acts as a ‘safety clutch” to prevent the tether from breaking under severe
ship motions.




Figure 1. Typical setup of VMP-Winch, sheave and line-puller. The winch, line-puller
and sheave must be in the same vertical plane. There is no slack in the tether because the
winch is pulling the VMP up.
VMP-Winch Manual                                                                           Page 6 of 33




Figure 2. Typical setup of winch, sheave and line-puller when the VMP is profiling down. Notice
that there is slack in the tether between the winch and line-puller. There is also slack in the tether
in the water near the ship so that the VMP can descend freely.
VMP-Winch Manual                                                                        Page 7 of 33


3 Getting Started
Because there are no international standards for electrical connections, line voltages and frequency
aboard ships, the electric motor for the VMP-Winch must be ordered for a particular ship and
application. A competent ship’s electrician must be assigned by the user to make the appropriate
electrical connections between the winch and the ship’s electrical system.

The VMP-Winch system is shipped dry and without any hydraulic fluid in its reservoir, hoses and
lines. Before the winch can be used, its hydraulic lines and hoses must be carefully purged of air.
Please, see section 0 for instructions on purging the air out of the hydraulic system.
VMP-Winch Manual                                                                          Page 8 of 33


4 System Description
4.1 Hydraulic Pump Unit
The hydraulic pump unit (Figure 3) consists of
   •   A 5 horsepower electric motor for the voltage and frequency ordered by the customer.
   •   a hydraulic pump,
   •   a reservoir (approximately 5 gallons or 18 l) for the hydraulic fluid,
   •   a fluid filter, and
   •   various fittings and valves.
A release valve allows the fluid to pass back to the tank in the event that the pump is started without
the hoses and winch attached. The valve is factory set and need not be adjusted. Do not operate the
pump without attaching both hoses to the winch. The winch can operate without the line-puller
attached. Do not operate the pump unit without hydraulic fluid. The reservoir should be kept about
3/4 full. Fluid in the reservoir must always be above the outlet in the reservoir that goes to the
hydraulic pump! Otherwise, air will be drawn into the hydraulic lines and damage the hydraulic
motors on the winch and the line-puller.

The reservoir holds approximately 18 l of fluid. The fluid can be any good brand of 32 weight
hydraulic fluid (e.g., Shell Telus 32). Try not to mix different types of fluid in the system. Consider
using the same fluid that is used on the ship of operation because the ship should have additional
fluid available, if fluid must be added at sea.

The pump unit should be secured in a covered position, away from rain and sea spray, and where it
receives an adequate airflow for cooling. Generally, it can be left on the base of the shipping box and
covered with the box when not in use. Never cover the pump unit while it is being used to prevent
damage from over-heating.
VMP-Winch Manual                                                                          Page 9 of 33




Figure 3. The hydraulic pump unit shown on its shipping base.




4.2 Winch
The winch is constructed of epoxy-painted aluminum alloy to minimize corrosion and to reduce
weight. It consists of a frame and a drum which is directly driven by a hydraulic motor (Figure 4).
Various hydraulic valves are mounted on both the motor and the winch frame. These control both
the winch and the line-puller. The winch also has a hydraulic pressure gauge. When the winch is
paying out the tether, this gauge indicates the total pressure applied to the winch and line-puller. The
pressure reading is slightly temperature dependent and decreases a little as the fluid warms up with
use. While the instrument is going down, the pressure reading will allow the winch operator to
repeat the speed of the previous profile or increase or decrease the speed based on relative pressure
readings. When the instrument is being pulled up, the pressure reading is proportional to the torque
on the drum. The tension in the line equals the torque divided by the radius of the line on the drum.
At no time should the pressure reading on this gauge exceed 950 PSI. If the VMP-Winch and its
controls are properly set up, the pressure readings will usually be below 600 PSI.
VMP-Winch Manual                                                                        Page 10 of 33




Figure 4. The VMP winch secured to the deck using ratcheting straps. This example is
holding 2500 m of tether.




4.3 Line-Puller
The line-puller (Figure 5) consists of an aluminum frame, a small hydraulic motor, three sheaves
(pulleys) and a guide cone. It should be folded down to one-half of its height, when not in use to
protect it from damage. When the line-puller is not used and it is not folded down, then the upper
hinged section should be secured to one side using a rope or elastic cord. This keeps it from
swinging and protects it from damage.

The tether is routed over the guide (top) pulley and under the drive pulley and then inserted into the
guide cone through the slot in the top of the cone. The idler pulley must be pulled down against its
spring to insert the tether into the groove in the drive pulley (Figure 5).
VMP-Winch Manual                                                                     Page 11 of 33

                                             .




Figure 5. The Line-Puller of the VMP winch   Figure 6. Line-Puller secured with
                                             ratcheting cargo straps to the aft end of a
                                             research vessel.
VMP-Winch Manual                                                                                                                                                          Page 12 of 33


4.4 Hydraulic Schematic
Experienced hydraulic fitters will find the hydraulic schematic useful (Figure 7). However, most
users of the winch may find the equivalent electric diagrams of the winch (found in Section 5.3)
more pertinent for understanding and using the VMP-Winch.


                                                                                  Winch Speed-Direction      B                   A
                    Pump Unit
                                                                                      Control Valve
                                                                            Pressure
                                                                             Gauge
    Relief Valve
                                              15 m Hose   P                                    2

                                                                                                                                                           Drum-Torque
                                                                                                                                                            Limit Valve


                                                                                                                                                                          5
                                                                                                                                                 3
                                                                                                                                                                                    Line-Puller
                      Pump                                                                                                                                     Disable             Power Control
     M                                                                                               P                     T
                                                                                                                                                                Valve
                                              15 m Hose   T
                                                                                                                                                     4
                                                                                                                                                                                            6
                           Oil Filter
                                                                                                                                                 Hydraulic Drum Motor              Flow Control
         Oil Reservoir                                                                                                                                                                Valve


               Legend
                P = pressure
                                                                                                                                                                    Line Puller
              T = tank (return)

                     Needle Valve
                                                                                                                                            15 m Hose

                      Gate Valve                                        7


                                                    Line-Puller Speed Control
                                                                                                     Linepuller                                                           Hydraulic Motor
                               Coupling                                                            enable/disable
                                                                                                                                            15 m Hose

 VMP-Winch Hydraulic Schematic                                                         1



            Sytech Research Version 2                                                              Line Puller Direction Valve

                   Design by   Chris MacKay
                               10-31-2006                                                                        A     Reference to Photograph




Figure 7. The schematic of the hydraulic system of the VMP-Winch and its line-puller.
VMP-Winch Manual                                                                           Page 13 of 33


5 Operation
5.1 Winch
The hydraulically powered line-puller takes the tether from the winch and feeds it over the side or
stern of the ship. The tether passes through an intermediate sheave which should be secured laterally
with a line if ship motions are severe or when there are strong winds. This sheave is generally
mounted in the “A” frame where possible. It can also be suspended from the boom of a crane (see
Figure 19). While the tether is going out (the VMP is descending), the winch drum is powered to pay
out its tether and make it available to the line-puller. The line-puller pulls the tether through the
intermediate sheave and sends it out through the guide cone and into the water. An observer must
watch the tether in the water to ensure that it is slack. One or two loops of tether in the water is ideal,
if the propeller is not turning. Keep the slack to less than one loop if the propeller cannot be stopped.
Feeding the tether out too quickly may generate too much slack in the water which may allow the
tether to be pulled into the ship’s propeller. Too much slack also increases response time when the
instrument needs to be pulled back up quickly because the slack tether must be pulled in before the
winch can start lifting the profiler. During descent, the line-puller direction valve is pulled into its
upper stop position (Figure 8). During descent of the VMP, there will be very little tension in the
tether between the winch and the line-puller, and this should be evident from the slack in the tether.




Figure 8. Details of the winch control lever and the control valves accessible at the front
of the winch.
VMP-Winch Manual                                                                           Page 14 of 33

To pull the VMP back to the surface, the line-puller direction valve is pushed into its lower stop
position (Figure 8). While the tether is being pulled in, the guide cone (Figure 5) will steer the line-
puller in the direction of the tether and guide it back onto the drive pulley. The drive pulley is free to
turn at this time (because the line-puller direction valve is in its lower position) and the winch itself
is doing all of the pulling on the tether.

The speed and direction of the drum on the winch is controlled by a lever at the right side of the
winch as you stand behind it. The lever has a center detent position which is the neutral position.
Pushing the lever forward will cause tether to pay out and allow the profiler to fall freely. Pushing
the lever further forward increases the speed of the drum. Pulling the lever back towards you (from
the neutral position) will cause the tether to be pulled in. Again, the speed is regulated by the
position of the lever. The direction control valve for the line-puller (Figure 8) must be in the down
position when the VMP is being pulled back to the surface. The line-puller valve must be in the up
position when the VMP is descending.

Caution: Always ensure that the speed and direction control lever is in the detent neutral position
when the pump unit is turned on. Otherwise the winch drum can unexpectedly start rotating and
possibly cause injury and damage.

Warning: Do not operate the VMP-Winch continuously above 600 PSI. Operating the winch
continuously at high pressures will cause excessive heating of the hydraulic fluid, the hydraulic
pump and the electric motor. Component failure will occur!

During a cruise in Monterey Bay in August of 2006 with a VMP-2000 and 2500 m of tether we
found that the tether tended to stick to itself on the drum when it was paying out the tether. This
sticking caused resonant oscillations in the tether between the winch and the intermediate sheave.
These standing waves could reach amplitudes of 1 to 2 meters without affecting the operation of the
winch and line-puller. A slight change in the speed of the drum (up or down) moved the forcing
frequency away from resonance and the oscillations dampened to a very small amplitude. The
pressure reading was approximately 220 PSI when paying out the tether at a rate of 1.2 m s-1 . The
ship speed was 0.8-1.0 knots, through the water (not relative to the bottom). When the VMP-2000
was pulled back to the surface, the pressure was deliberately limited to 600 PSI. There is a
significant drag on 2000 m of tether in the water. At 600 PSI, the initial speed of the tether is fairly
slow ( ~ 1.0 m s-1 ). The speed of the tether increases as the radius on the drum grows and the drag on
the line decreases. In Monterey Bay, the line speed reached 1.5 m s-1 when the profiler was near the
surface. Because the pressure was carefully controlled, there was no abnormal wear or stress on the
tether and the line-puller even after 130 profiles to nearly 1200 m depth and up to 2000 m of tether
in the water.

5.2 Line-Puller
To use the line-puller, pivot the blue frame up to its vertical position while carefully holding the
cone assembly which is free to swing. Install the 3/8” bolt at the top of the yellow frame to secure
the blue section into place. This should be done by two people working together. When the line-
puller is not in use, or during rough seas, the upper pivoting part of the line-puller must be restrained
with straps, rope or shock cords so that it does not swing back and forth and get damaged.
VMP-Winch Manual                                                                                                            Page 15 of 33

The tether goes over the top sheave (aluminum), and then under the driven sheave (PVC) as shown
in Figure 5. Pull down on the idler to feed the tether in between it and the lower sheave, and then
insert it in to the guide cone. The slot in the cone is intentionally tight so that the tether can not
escape from the cone in normal use.

5.3 Equivalent Electrical Diagrams
An understanding of the VMP-Winch system may be gained from examining the equivalent
electrical diagram of the hydraulic connections. We make the following associations in the electrical
equivalent diagrams.
       •   Diode ↔ one-way or check valve.
       •   Single-pole switch ↔ on-off ball valve.
       •   Double-pole switch ↔ direction valve.
       •   Variable resistor ↔ multi-turn needle valve. The resistance can range from zero to infinity.
       •   Voltmeter ↔ pressure gauge.
       •   Zener diode ↔ pressure release valve.
       •   Current flow ↔ fluid flow.
       •   Voltage ↔ pressure.
The internal complexity of the speed-direction valve is greatly simplified.

                                                                              M
                                         Line-Puller
                                       Direction Valve                  Line-Puller Motor




                                                Line-Puller
                                               Speed Valve

                       Winch Neutral



                V
                                                                                                          Emergency
                                                                                                          Over-Ride
              Gauge                                                                                         Valve


                            Winch
                        Speed-Direction
                           Control


                                                          Line-Puller
                                                         Power Valve                                         Drum-Torque
Pump                                                                                           M              Limit Valve

                                                                                            Winch Motor




Figure 9. The winch system when the speed-direction lever is in the neutral (or detent) position.
Winch drum and line-puller are not rotating. Thick lines show the fluid flow. With the lever in
neutral, fluid re-circulates freely to the pump.
VMP-Winch Manual                                                                                                            Page 16 of 33


                                      Line-Puller
                                                                                    M
                                    Direction Valve
                                                                             Line-Puller Motor




                                  Line-Puller
                                 Speed Valve



                                Winch Pulls in
            V

          Gauge                                                                                            Emergency
                                                                                                           Over-Ride
                                                                                                             Valve


                           Winch
                       Speed-Direction
                          Control


                                                        Line-Puller
                                                       Power Valve                                           Drum-Torque
Pump                                                                                             M            Limit Valve

                                                                                             Winch Motor




Figure 10. Configuration when the winch is pulling up the VMP. The motor on the line-puller is not
powered and rotates freely because it is isolated by the line-puller direction valve. The line-puller
power valve is not active because it is by-passed.

                                    Line-Puller                       M
                                  Direction Valve
                                                                Line-Puller Motor




                             Line-Puller
                            Speed Valve

                    Winch Pays Out


           V
                                                                                                           Emergency
         Gauge                                                                                             Over-Ride
                                                                                                             Valve


                          Winch
                      Speed-Direction
                         Control


                                                       Line-Puller
                                                      Power Valve                                            Drum-Torque
Pump                                                                                             M            Limit Valve

                                                                                            Winch Motor




Figure 11. Configuration when the winch is paying out line. Power is applied to the motor on the
line-puller due to the pressure drop across the power valve and the winch motor. The pressure relief
valve (Zener diode) across the motor is blocked by the one-way valve. Thus, when the winch pays
out line, there is no pressure limit on the winch motor.
VMP-Winch Manual                                                                                                    Page 17 of 33


                                     Line-Puller
                                                                     M
                                   Direction Valve
                                                               Line-Puller Motor




                          Line-Puller
                         Speed Valve


                     Winch Pulls in

           V
                                                                                                 Emergency
         Gauge                                                                                   Over-Ride
                                                                                                   Valve



                          Winch
                      Speed-Direction
                         Control


                                                      Line-Puller
                                                     Power Valve                                     Drum-Torque
Pump                                                                                  M               Limit Valve

                                                                                   Winch Motor




                                                                                                 Over-Pressure




Figure 12. Same as Figure 10 but with too much pressure on the winch motor. The pressure has been
limited by the pressure relief valve (Zener diode). Note that the pressure is not limited when the
winch is paying out line.
VMP-Winch Manual                                                                        Page 18 of 33


6 Purging the Hydraulic System
The system must be carefully purged of air before the winch can be used safely. There will be air in
the system when it is shipped from the factory and there may be air in the system if changes where
made, such as the installation of new hoses. Please use the following procedure if there is air in the
hydraulic system.
   •   If there is a tether on the drum, secure the tether to the drum so that the drum can rotate
       without causing any damage.
   •   Fill the reservoir with hydraulic fluid.
   •   Connect the electric motor to the electric source.
   •   Connect the hoses to the winch and to the line-puller.
   •   If the pump unit is being operated for the first time, then:
            o Remove the orange cover from the adapter between the motor and the pump.
            o Confirm that the “lovejoy” coupling is disengaged and that the set-screws in the two
                halves of this coupling are tight using a 3/32 inch hex (Allen) wrench.
            o Turn on the motor for 2 seconds and confirm that the shaft rotates in the counter-
                clockwise (CCW) direction. If the rotation is not CCW, have an electrician correct
                the electrical connections.
            o Disconnect the electrical supply to the motor.
            o Loosen the set-screw on the pump side of the lovejoy coupling.
            o Engage the coupling to the pump and re-tighten the set-screw.
            o Replace the orange cover
   •   Pull the line-puller direction valve into its up position. Set the winch speed-direction lever
       into its neutral detent position.
   •   Turn on the electric motor for 3 seconds and then turn it off for at least 1 minute. You will
       hear air bubbles in the reservoir. The pump will make a loud whining sound if it is pumping
       air-entrained fluid.
   •   Repeat turning the motor on for 3 seconds and off for 1 minute until you cannot hear the air
       bubbles in the reservoir.
   •   Run the pump for 5 minutes. It should make a steady sound.
            o If the sound is unsteady, then there is still air in the hoses. Turn off the motor for 15
                minutes and run it again for 30 seconds. Repeat until the sound is steady. This
                procedure flushes the hoses connecting the pump to the winch and the winch to the
                line-puller (reference Figure 9).
   •   Check the fluid level in the tank and add fluid, if necessary.
   •   Turn on the motor and slowly push the winch speed-direction lever forward about 20%. The
       drum will start to turn and you will hear the sound of the pump change when air reaches the
       reservoir. When you hear the change in sound, return the lever to neutral, turn off the pump
       motor, and wait for 2 minutes for the air bubbles to rise out of the reservoir.
   •   Repeat the above step but pull the speed-direction lever back about 20%.
VMP-Winch Manual                                                                       Page 19 of 33

   •   Repeat running the winch forwards and backwards until the sound of the pump is steady.
       This flushes the air from the lines in the winch.
Symptoms of air in the hydraulic system include foaming of the fluid in the reservoir, excessive
noise in the hydraulic motors as air is compressed and re-expanded, irregular hydraulic pressure, and
irregular winch speed. It may take several hours of operation for all of the air to get completely out
of the system.
VMP-Winch Manual                                                                          Page 20 of 33


7 Adjustments of Line-Puller Power and Speed Valves
The hydraulic motor in the line-puller is driven by the pressure at the inlet to the speed-direction
valve on the winch. The line-puller can be adjusted at two points — the line-puller power valve and
the line-puller speed valve.

The line-puller power valve (Figure 13) acts as a load in series with the winch motor. This load is
only active while paying out the tether. Turning this valve clockwise (threading it in) will increase
the pressure available to drive the line-puller and decrease the speed of the winch. Once the line-
puller power valve is properly set it does not need to be adjusted during profiling.

Caution: This valve should be turned in as little as possible. It must be adjusted as described at the
end of this sub-section. Turning this valve clockwise (inward) further than necessary causes an
excessive pressure drop across the winch (back pressure) which reduces the speed of the winch,
increases the hydraulic pressure, wastes power and leads to overheating of the system.




Figure 13. Close-up view of the control valves around the motor on the winch. These
controls do not need to be adjusted during normal use of the winch.



The line-puller speed control valve (Figure 8) gives the operator control of the speed of the line-
puller. It is placed conveniently close to the other controls on the winch so that the operator can
make small adjustments during a profile. This valves directs the back-pressure created by the line-
puller power valve (described above) to the motor on the line puller. On a properly adjusted winch,
this speed control valve is the only valve that needs to be adjusted to change the speed of the line-
puller.
VMP-Winch Manual                                                                             Page 21 of 33

To operate the system properly, the line-puller speed must be adjusted so that the tether between the
winch and the intermediate sheave sags but does not touch the deck. It is not necessary that the
tether be tight. In fact, a tight tether is undesirable. If the line-puller turns too quickly for the rate of
payout from the winch, then there will be significant tension in the tether between the winch and the
line-puller (and no sag in the tether because of the tension). The drive pulley (Figure 5) will slip over
the tether and abrade the outer jacket of the tether. If the line-puller turns too slowly, then the tether
between the winch and the line-puller will sag and drag on the deck in front of the winch.

When the line-puller power and speed valves are properly adjusted, the speed of the line-puller will
be proportional to the speed of the drum on the winch. If the winch speeds up, the line-puller speeds
up by the same proportion. During a deep profile some small adjustments of the speed valve may be
needed. As the radius of the tether on the drum decreases the linear speed of the tether will also
decrease and the sag between the winch and the line-puller will disappear. Slightly decreasing the
speed of the line-puller will return the system to proper operation. Also, as the hydraulic fluid warms
up with operation of the winch, the line-puller may require a slight adjustment of its speed.

Adjust the line-puller power and speed valves using the following procedure. The first phase is a
rough adjustment.
    •   Do not put the tether through the line-puller. Leave it on the drum.
    •   Secure the tether to the drum so that the drum can rotate without causing any damage.
    •   Connect the electric motor to a suitable power source, and connect the hoses from the pump
        unit to the winch and from the winch unit to the line-puller.
    •   Turn the line-puller power valve fully counter-clockwise. This is the fully-open position
        where it supplies no power to the line-puller.
    •   Turn the line-puller speed valve fully counter-clockwise (fully open) and then 2 turns
        clockwise.
    •   Pull the line-puller direction valve up so that it directs fluid to the line-puller.
    •   Push the winch speed-and-direction lever forward so that the drum spins in the direction of
        paying out cable. Push the lever so that the drum rotates at about 1 m s -1 at the outer radius of
        the drum. (It may help to mark the edge of the drum with a piece of tape.)
    •   The line-puller drive pulley should turn very little, if at all.
    •   Turn the line-puller power valve clockwise for one or 2 turns and no more than 3 turns at
        most. The drive pulley should spin. Adjust the line-puller power valve in or out a little (no
        more than 1 turn) so that the speed of the drive pulley on the line-puller is about 1 m s -1 at its
        outer radius. Placing a mark on the pulley may help you judge the speed. The exact speed is
        not important. Verify that the pressure gauge at the winch reads less than 300 PSI.
This concludes the first phase of adjustment. The line-puller pulley turns at approximately the right
speed to match the drum with very little pressure applied to the winch system.
The second adjustment phase is made with the tether going through the line-puller.
   • Thread the tether through the line-puller as shown in Figure 5.
   • Try to mount the sheave so that the line from the sheave enters the line-puller at about 45º.
       Align all the winch, sheave and line-puller into a single vertical plane.
VMP-Winch Manual                                                                           Page 22 of 33

   •   Make sure that there is a little slack in the tether between the line-puller and the winch.
   •   Make sure that the line-puller speed valve is still 2 turns in from fully open.
   •   Momentarily run the winch at about 1 m s-1 and watch how the line-puller draws the cable
       from the winch.
          o If the slack disappears, then the line-puller is running too fast. Turn the line-puller
              power valve one-half turn counter-clockwise and put some slack back into the tether
              by hand. Continue this test and keep turning the line-puller power valve counter-
              clockwise until the tether slack is steady.
          o If the slack grows during the test, then the line-puller is spinning too slowly. Turn the
              line-puller power valve clockwise by one-half turn and put some slack back into the
              tether by hand. Repeat the test and keep turning the line-puller power valve clockwise
              until the slack in the tether is steady.
It may help to mark the tether at regular intervals, such as every 1 m, to judge the speed of the line
coming out of the line-puller.

The final adjustment must be made at sea because the weight of the tether between the line-puller
and the sea surface cannot be easily simulated on land. Also, the tether may behave differently when
it is wet. If the second phase of adjustment was made at sea, then the line-puller is ready for use,
otherwise, repeat second adjustment phase at sea.

The usual position for the line-puller power valve is 2 turns clockwise from its fully-open (counter-
clockwise) position. If the line-puller speed valve is also at about 2 turns clockwise from fully open,
then the line-puller power valve should never have to be more than 4 turns clockwise. If 4 or more
turns are required to get steady slack in the tether at 1 m s -1 , then there may be a blockage or air in
the hydraulic system. Purge the system following the instructions in Section 0. If it still takes more
than 4 turns, please contact Sytech Research.
Finally, it is important that the pressure never exceed about 300 PSI when using the line-puller. Very
little power is required to operate the line-puller because there is very little tension in the tether. The
power directed to the line-puller is not available to the motor on the winch drum.
Once the line-puller power valve is adjusted there is little need to adjusted it further. However, if it
is necessary to pay out the tether at a rate much faster than 1 m s -1 , because for example the ship is
steaming unusually fast, then it may be necessary to turn the power valve clockwise for an additional
¼ or ½ turn. The power valve should be returned to its previous position as soon as possible.

7.1 More notes on adjusting the line-puller
There are three controls for the line-puller. The first is the line-puller direction valve. When this
valve is pushed down, there is no hydraulic pressure at the motor on the line puller and it turns freely
in either direction. The direction control valve is pushed down when the profiler is being pulled back
to the surface. The direction valve is pulled up when the VMP is profiling down. In this position,
hydraulic power is supplied to the motor on the line-puller.
VMP-Winch Manual                                                                         Page 23 of 33

The second control on the line-puller is the line-puller speed valve. It is mounted on the “front” of
the winch near the winch speed and direction control lever. This is the valve that must be used to
make small adjustments to the speed of the line-puller during profiling. This valve has no effect
when the line-puller direction valve is in the down position.

The third control is the line-puller power valve. It is located on the side of the winch near the winch
motor. This valve controls the maximum power available to the hydraulic motor on the line-puller.
This valve does not need routine adjustment after it has been properly set. This valve has no effect
when the line-puller direction valve is in the down position.

Both the line-puller speed and power valves control the amount of hydraulic fluid passing through
them and on to the line-puller motor. Rotating these valves clockwise closes the needle port and
reduces the amount of fluid flow. Turning the valve counter-clockwise, increases the fluid flow. If
either valve is turned all the way clockwise it will block the fluid flow. There are colored bands at
the bottom of the line-puller speed control knob. These bands are visible when the valve is fully
opened (counter-clockwise), and they are covered when the valve is fully closed (clockwise) and
blocking fluid flow. Some bands are visible at intermediate settings and can be useful as a reference
for where the valve is set and for making small adjustments. Also, look at Figure 9, Figure 10,
Figure 11, and Figure 12.

The line-puller power valve is in series with the main hydraulic motor turning the drum. The power
valve incorporates an internal check valve in parallel with the needle valve. This check valve allows
free passage of fluid in one direction but forces the fluid to go through the needle valve when flow is
in the other direction. When the winch is pulling the tether up and, therefore, the line-puller is not
being driven, this check valve allows the fluid to pass freely around the valve. When the tether is
going out, the fluid is forced to go through the needle valve.

The power valve must be carefully set using the adjustment procedure described in Section 7. If this
valve is turned too far clockwise it will degrade the performance of the winch and cause the fluid to
get hot. Once properly set, this valve should require no further day-to-day adjustment. Note that as
power valve is turned clockwise the pressure showing on the gauge will increase, and the rotation of
the drum will decrease.

CAUTION: If the power valve is turned completely clockwise, the winch would not turn, and there
would be a very high pressure reading on the gauge when the main winch control valve is pushed
forward to feed out the tether.

The line-puller is connected to the winch at the same point as the pressure gauge. Fluid flows from
this point through the speed valve and the direction valve. The pressure showing on the gauge is the
amount of pressure available to drive the line-puller. By adjusting the power valve you can increase
or decrease the pressure available for the line-puller. In normal operation this pressure also increases
and decreases with changes in the speed of the drum (tether going out).
VMP-Winch Manual                                                                           Page 24 of 33

7.2 Slippage
If the line-puller is operated at a speed faster that the tether is coming off the drum, then it will wear
out the drive pulley and abrade the tether. If the drive pulley on the line-puller is slipping over the
cable, then increasing the line-puller speed will simply make it slip more, and it will not increase the
speed of the tether. The line-puller was designed to be as gentle as possible with the tether. The line-
puller does not have the power to pull cable off the winch. It merely pulls in the slack of the tether
line between the winch and the line-puller. It is not necessary for the line-puller to pull the tether
tight. The tether can sag as long as it does not touch the deck. The system is working properly when
the tether is coming off the winch and getting over the side of the ship without touching the deck.

One indication of slippage is small orange particles of the tether jacket being sprayed from the drive
pulley on to the outside of the guide cone on the line-puller.

It may be useful to tape or paint a stripe across each of the large pulleys on the line-puller as a visual
guide. At all times they should be rotating at about the same rate. The two pulleys have slightly
different diameters, and there may be a few percent of slippage, but someone standing beside them
should be able to confirm that they are turning at the same rate. If the drive pulley is faster than the
top pulley then the line-puller is slipping, and must be slowed by turning the speed valve clockwise.
If it is necessary to turn the speed valve almost fully clockwise, then there is too much power
available. The power is reduced by turning the power valve counter-clockwise.
VMP-Winch Manual                                                                         Page 25 of 33


8 Drum-Torque Limit
The drum-torque limit valve (Figure 13) is set at the factory to release at 950 PSI. This valve limits
the maximum torque that can be applied to the drum to 270 foot-pounds (370 N-m). This valve
should not be adjusted. Please contact the factory for instructions if this valve does not appear to be
operating properly, that is, the pressure readings exceed 950 PSI while the VMP is being pulled
upwards.

8.1 Emergency Over-ride
Unexpected conditions at sea may require that you have more line tension then can be supplied
within the 950 PSI limit of the drum-torque limit valve. In such unusual cases, the operator must use
good judgment before activating the disable valve (Figure 13).

Closing the disable valve, blocks the drum-torque limit valve, and allows the full pressure to be
applied to the winch. This must only be done in an emergency. The winch must not be operated
routinely with the disable valve closed. The maximum torque on the drum and, hence, the maximum
tension in the tether, is only limited by the pressure produced by the hydraulic pump and this
pressure can easily reach 1400 PSI. The maximum tension can reach 500 pounds (2300 N).
Routinely reaching tensions above 200 pounds will damage the tether.

One potential emergency may be a sudden increase in ship speed (possibly to avoid a collision). The
high speed of the ship may create enough tension to cause the drum-torque limit valves to release
and allow the drum to rotate and pay out the tether. If the payout continues, then eventually there
will be very little tether left on the drum. To avoid paying out all of the tether and, thus, losing the
VMP, the operator must close the emergency over-ride valve to stop the drum from turning. The
tether may sustain damage, but the instrument will remain attached as long as the tension remains
below 1400 pounds (6400 N).
VMP-Winch Manual                                                                       Page 26 of 33


9 Winch Controls Summary

Item                            Description and Comments
Main Winch Control Lever           •   No drum rotation when in neutral (or detent) position
Figure 8.                          •   Push forward to pay out the tether. VMP going down.
Section 4.2 and 5.1                •   Pull back to draw in the tether. VMP going up.
                                   •   Tether speed is proportional to lever position.
Line-Puller Direction Valve        •   Pull to up position when profiling down.
Figure 8                           •   Push to down position when pulling VMP up.
Section 5, 7, and 7.1
Line-Puller Speed Valve            •   Turn clockwise to decrease speed of line-puller and to
Figure 8                               increase the sag of the tether between the winch and the
Sections 4.3, 5.2, 7, and 7.1          line-puller.
                                   •   Turn counter-clockwise to increase the speed of the
                                       line-puller and to reduce the sag of the tether between
                                       the winch and the line-puller.
Line-Puller Power valve            •   Sets maximum power available to the line-puller.
Figure 13                          •   Should not be adjusted during profiling after it has been
Section 5.2, 7, and 7.1                properly set.
                                   •   See sections 5.2, 7, and 7.1 for properly setting this
                                       valve.
Drum Torque Limit Valve            •   Limits the maximum torque on the drum of the winch.
Figure 13                          •   Should not be adjusted during profiling.
Sections 7.1                       •   See section 7.1 for properly setting the drum-torque
                                       limit valve
Emergency Over-Ride Valve          •   Use only in an emergency when pulling up the VMP to
Figure 13                              remove the maximum torque limit on the winch motor.
Section 8.1                        •   Close valve temporarily to supply higher pressure to
                                       winch motor and to increase the tension in the tether.
                                   •   Open valve for normal operations.
VMP-Winch Manual                                                                       Page 27 of 33


10 Electric Motor
The pump unit may be single or three phase and may be 50 or 60 Hz. The 50 Hz 3 phase unit can be
configured for 220/380/or 460 volts. Always ensure that the winch controls are at the neutral (center)
position before you start the pump unit.

The electric motor and its on-off switch must be installed by qualified personnel.
VMP-Winch Manual                                                                         Page 28 of 33


11 Mounting the System on a Ship
There are various ways to mount the equipment depending on the type of deck surface. With a steel
deck, and if you can weld to the deck, fabricate 8 steel plates 6” x 2” and weld ¾’’ nuts to the plates.
Bolt these to the winch and line-puller with the long axis of the plates at right angle to the frames
and then weld the ends of the steel plates to the deck. The winch and line-puller can then be unbolted
and reinstalled as required. The steel plates can be removed with a grinder when necessary and
reused. A wooden deck may require construction of a mounting bracket to use existing holes in the
deck.

Where welding is not feasible, the winch and line-puller may be secured using ratcheting cargo
straps (see Figure 4 and Figure 6 ). Do not use chain load binders because they may exert too much
force.
VMP-Winch Manual                                                                   Page 29 of 33


12 Lifting the Components
Please lift components as shown in Figure 14 and Figure 15.




Figure 14. Lifting the hydraulic pump unit.




                                                   Figure 15. Lifting the winch.
VMP-Winch Manual                                                                       Page 30 of 33


13 Slip-ring Installation
The slip-rings are mounted at the end of the shaft with four ¼ -20 x1/2” cap screws. These cannot
be tightened with an Allen wrench. Instead, start by tightening by hand, and then carefully use
pliers to finish.

The slip-rings should be restrained from rotating with a tie-wrap. See Figure 16and Figure 17.

   ALWAYS ENSURE THAT THE WINCH CONTROL IS IN THE NEUTRAL POSITION
                 BEFORE YOU TURN ON THE PUMP UNIT




Figure 16. Slip-ring attached to the shaft of the   Figure 17. Same as Figure 16 but with the
winch.                                              guard bracket installed.
VMP-Winch Manual                                                                                     Page 31 of 33


14 Specifications
Cable capacity (0.270 inches)                2500 m (22 wraps)
Drum width                                   15 inches, 0.38 m
Drum inner diameter                          20 inches, 0.51 m
Drum outer diameter                          35 inches, 0.89 m
Maximum Torque 1                             380 ft-lb, 516 N-m @ 1300PSI, 9.0 MPa
Maximum permitted torque 2                   270 ft-lb, 370 N-m @ 950 PSI, 6.6 MPa
Maximum tension, drum empty                  320 lb, 1400 N
Maximum tension, drum full                   200 lb, 900 N
Maximum tether speed pulling in              1.5 m s-1
Maximum tether speed paying out              2.2 m s-1
Maximum continuous                           600 PSI, 4.1 MPa
operating pressure
Operations above 600 PSI                     Less than 5 minutes
Electric motor                               5 HP, 3.5 kW
Direct hydraulic supply 3                    10 GPM @ 1000 PSI, 40 LPM @7 MPa
Winch                                        32.25 X 40 X 46.75 inches
Length, width, height                        0.819 X 1.016 X 1.187 m
Line-Puller, Length, width                   24 X 24 inches, 0.61 X 0.61 m
Height                                       54 inches, 1.37 m, folded down
                                             92 inches, 2.34 m, folded up.
Pump, length, width, height                  30 X 23 X 17 inches, 0.76 X 0.58 X 0.43 m
Weight                                       650 lb., 295 kg, Winch
                                             110 lb, 50 kg, Line-Puller
                                             220 lb, 100 kg, Pump
Shipping Boxes                               LXWH
Winch                                        34.5 X 45 X 54.0 inches, 0.88 X 1.14 X 1.37 m
Line-Puller                                  28.0 X 63 X 29.0 inches, 0.71 X 1.60 X 0.74 m
Pump                                         27.5 X 34 X 22.5 inches, 0.70 X 0.86 X 0.57 m
Shipping Boxes Full Weights
Winch                                        720 lb, 327 kg
Line-Puller                                  265 lb, 107 kg
Pump                                         250 lb, 114 kg



1
  Can only be reached with drum-torque limit valve open which should only be done in an emergency.
2
  Automatically imposed by the drum-torque limit valve.
3
  For customers with their own source of hydraulic power.
VMP-Winch Manual                                                                        Page 32 of 33


15 Illustrative Photographs




Figure 18. The VMP winch paying out cable to        Figure 19. Companion photograph to Figure 18
the line-puller during a profile. Note the slight   showing the tether going over the sheave and into
sag in the tether.                                  the line puller. Note the slight sag in the tether.
                                                    The sag is much smaller between the line-puller
                                                    and sheave because there is more tether being
                                                    suspended between sheave and winch than
                                                    between the sheave and the line-puller.
VMP-Winch Manual                                                                      Page 33 of 33




                                                    Figure 21. Close-up view of the sheave available
                                                    with the VMP.




Figure 20. View from winch to line-puller. The
section of tether between the winch and sheave
is fluctuating laterally because of strong winds.
The section between the sheave and the line-
puller is more steady because it is shorter and
being weighed-down by the tether between the
sheave and the winch.

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