The AHT winches can be delivered with various features and customized adapted. TTS can now offer 200 tons, 300 tons, 400 tons, 500 tons and 550 tons winches in various models like for example drums, drum sizes and spooling devices.
According to the company: – We offer our products with high pressure hydraulic (HPH) drive. Today these winches are generally delivered with low pressure hydraulic drive, but our high pressure drive solution is fully adapted to the AHTS market and can match any requirement from our customers. We have been working very close to some of the major ship designers and are very confident with our solutions. By using HPH drive we can easily adapt to new requirement and future demands from owners, class society and authorities to technology for use on AHT winches which we are working on already now and hope to launch in 2008. Today there are several misunderstandings in the market for low pressure hydraulic (LPH) vs HPH. These misunderstandings are especially towards the following topics:
• Dynamic breaking
• Quick release
The winch power requirement are the same whatever drive solution used, so based on this the LPH system requires five times as much oil flow as the HPH system to create the same effect.
TTS: – With this you will get five times as big oil pillar between valve and motor acting as a spring. You also have to accelerate a larger mass substance to a wanted speed and this will also require longer time. Larger components because of larger oil flow also results in larger inertial masses.
– We are using high torque low speed radial piston motors from Hägglunds. These motors have supreme performance and are well adapted for AHT winch drives.
– When it comes to oil cleanliness our system can operate with a cleanness of NAS 9. We are using return filters and blocked filter alarms to avoid damage on the equipment. For example LPH require typical cleanliness of 9 -11 which in fact are almost the same as HPH. And due to this fact the LPH more or less require the same when it comes to flushing and installation as for HPH.
TTS´ 500 tons AHT winch. Photo:TTS
.. and on Ambient temperature: – The HPH system we are using will of course depend on the oil viscosity. In order to keep the viscosity in preferred range we use oil coolers.
– The motor we are using have been tested and can be documented for high vibrations and high g-forces. Some HP motors have been tested for 24 hours with 25g vibration.
Use of equipment: The motors are designed for 40.000 hours with half pressure and max rpm and 4.000 hours with full pressure and max rpm.
TTS on: Dynamic breaking
– HPH motor has functionalities which overcomes LPH. We can do controlled pay out (rendering/dynamic braking) with the motors. When it comes to over speed we can over speed the motors 2-3 times the rated speed as long as we have control over the case temperature. LPH is extremely sensitive to over speed, so when use in dynamic braking special attention has to be paid to the LPH motors.
TTS on: Quick release
With HPH solution we have two opportunities to do quick release. The first solution is to release the claw couplings with max load or to freewheel the motors. LPH hasn’t the possibility to freewheel the motors, so they need to release the claw coupling (clutch) with full load. This is a very critical manoeuvre and requires high forces.
.. and on: Torque
The motors we are using has supreme power density. In order to get the same torque as LP motors we need to put on more motors, but again, since our power density is higher than the LHP we are quicker when it comes to acceleration and de acceleration of the winch.
A big disadvantage for the LPH used in marine industry is the weight. The motors are 4-5 times heavier then HPH motors we are using, and not to forget the tubes/pipes and power packs. This should concern the ship owners since it limits the vessels payload.
The HP motors can supply much more energy pr. litre than LP motors. The power density is superior compared to LP motors and also compared to AC motors.
Sales manager Sverre Mowinckel-Nilsen at TTS Offshore Handling Equipment:
– The company tells that their main focus on the winch design has been to deliver winches with compact design so they can be space saving on the vessels together with focus on delivering winches that have rugged design making them able to handle the enormous strengths exposed in the anchor handling work. Safety is also one of the focus areas for TTS anchor handling winches. This is an area where more and more focus will be given. TTS are working on several solutions to this, especially on the “safer anchor handling deck” area.
– AHTS vessels are getting larger and larger, but they are filled with more and more equipment so that deck space is getting more and more critical.
– We have seen on our design that our customers will be able to get a more compact winch than earlier. The high pressure drive system is also much more space saving than the low pressure drive system and we are very certain that we have managed to offer a technical solution that will be of great interest for the AHTS marked. Our control systems, which is one of the most important components in our delivery is designed by people who have long experience in this field. We are for example delivering remote assistance by Internet with the systems. This means that we can do remote assistance to all our customers from our office here in Norway 24 hours a day. We will be able to seek through the complete system and can repair if possible or we can localize what’s wrong, send our service engineers and then do the repair much more effectively.
– We also see that we can offer our winches very competitive both in price and delivery times. We have production facilities ready for all our winches. We can also deliver all other winches to AHTS vessels like anchor-windlass, capstans, rope reels and tugger winches, according to Sverre Mowinckel-Nilsen.
Active heave compensated subsea winches
TTS Offshore Handling Equipment is also working on advanced active heave compensated subsea winches. – We are designing and producing both winches and control systems for all active heave compensated offshore cranes delivered through TTS Marine Cranes. This is winches from 60-250 tonnes and we are also aiming for winches up to 400 tonnes for the largest cranes. These advanced winches operates on water depths up to 3000 meters. Our knowledge on these winches is also being used for our anchor handling/towing winches design, and especially on our control systems. Our subsea winches are designed for use both on TTS’ offshore cranes and for deck on offshore vessels for use on for example A-frames, says Sverre Mowinckel-Nilsen.
TTS consist now of over 1250 employees all over the world and is one of the major suppliers of ships equipment. To the offshore market TTS can offer cranes in various sizes, anchor handling/towing winches, and a lot of other equipment like moon poles, smaller winches like anchor windlass, tugger winches, capstans. TTS is aiming to be a more and more complete supplier to the offshore segment. Earlier this year TTS acquired Sense EDM. This is a company that delivers drilling equipment both onshore and offshore and will be a focus area in the TTS Company aiming for the offshore segment.