Underwater winches are designed and manufactured specifically for use underwater and subsea. Uses include general rigging, pull-in, pull-down, docking, anchoring, load control, load holding, load stabilisation, recovery. Winches need to be attached to foundations to react the pulling or lifting load. Foundations can be; suction anchors, clump weights, custom built frames. Winches can be suspended off anchor supports to align with the load as the rope or cable is tensioned. Underwater winches can be used with; steel wire rope, stainless steel rope, fibre rope or cable. Winches can be used with special cables with power and control wiring. These winches have slip rings. Winch power can come from the surface, the shore or batteries. They can be direct driven by ROVs with rotary torque tools, hot stabs, and submersible connectors. Control can be; local by diver, ROV or submersible. Control can be remote from the surface or the shore. Underwater winches or subsea winches are used in many different industries, oil and gas, tidal generation, oceanography, marine research, marine renewables, civil engineering, marine construction, cable laying, cable recovery, underwater maintenance, hydro dams, utilities, aquaculture, salvage. Underwater and subsea winches are a powerful tool for divers and ROVs.
Renowned for simple, high quality technology solutions, ALL OCEANS have developed the patented AC-ROV for their partners AC-CESS Co UK Ltd. The all new concept video camera and sensor platform has 6 identical thrusters giving the operator all the viewing control that will ever be needed.
Four “full-bore” vectored horizontal thruster units give equal forward, sideways and pan control, whilst two vertical units give powerful up, down and pitch control. You can fly upside down or loop the loop if you want. A one handed (left or right) 5-axis controller makes for a very simple and versatile operator interface. “Flight Freeze” is a further very powerful feature that can be selected, refreshed or terminated with the press of a button.
A major issue with small vehicles is of course their limited ability to pull any length of cable through the water. The solution is to ballast the tether cable a distance back from the ROV or use a Tether Management System. Rest assured, ALL OCEANS are well qualified to take this into account.
A tether management system, also known as a TMS, is a type of underwater winch. It is used in conjunction with an ROV for increased utilisation. An ROV is a submersible and can be manned or unmanned. TMS are used with ROVs and submersibles on ships, fixed platforms, offshore in shallow and deep water. The winch stores cable, known as a Tether. It provides power and communication. The cable is nearly neutral in water. It can be buoyant so that it tends to float. A unique type of winch, it dispenses cable even without a load on it. A TMS is heavy in water. It is suspended on a surface lift cable called an Umbilical. The TMS is anchored at depth by its weight. The ROV is relatively free to move around on the end of the tether cable and to return to the TMS between jobs. A TMS allows long dive durations. The ROV can return to the TMS and be powered down. This rests the ROV and the operator. An ROV operator is also call the pilot. There are two configurations of TMS; Top Hat is a single package that sits on top of the ROV; Garage accommodates the ROV inside its frame. Top Hat systems have an ROV latch. Garage systems don't need an ROV latch. Garage TMS are less versatile and tend to be bigger. Top Hat TMS are smaller and have less drag. There two types of TMS winch mechanism. Bail arm type, and driven drum type. Bail arm systems are limited in how much tether they can store and handle. Driven drum winches do not have storage limits, are generally more reliable. Driven drum TMS use slip rings.
A launch and recovery system (LARS) is an arrangement of equipment used to deploy and recover equipment from the sea to a ship or vessel. LARS are used for handling ROVs, Diving Bells (SDC), Dive Baskets, Wet Bells, Atmospheric Diving Suits (ADS), Submarines and any form of submersible including autonomous ROV, and all manner of tools used for survey, sampling, drilling, coring, excavation, trenching, ploughing, seabed stabilisation etc. Types of LARS are A-Frame, Crane, Gantry, Integrated, Moonpool, Cursor, Free Fall, Portable, Lightweight for use to handle Diving bells and equipment, ROVs or any type of submersible equipment or tool. LARS can be temporary or permanent installations on ships, vessels, semi-submersibles, fixed, floating or jack-up platforms. The main elements of a LARS are the lift frame, lift winch, umbilical winch, power pack, controls, snubber, guide wires, guide rails, sheave wheels, trolley, rails, guides, cursor.
Our ethos at All Oceans Engineering is to deliver professional and cost-effective solutions to mechanical underwater handling affairs. As specialists in engineering services such as mechanical handling underwater servicing, we offer products and resources to ensure premium satisfaction for our customers’ requirements.