Piggy-back hatch covers
MacGregor piggy-back hatch covers are an ideal solution when deck space is tight. They offer a compact, efficient design and are used when it is not possible to accommodate folding, side-rolling or end-rolling covers.
The piggy-back system always comprises two panels, with one panel being raised high enough for the other to roll underneath and to support the lifted panel on to its ‘back’. Both panels can then be rolled back and forth.
The system can either be applied to a pair of hatch openings or to the two panels of a single hatch opening. If the number of panels exceeds two, the system is called ‘stacking'.
The standard high lifter system consists of four hydraulic cylinders. Reliable synchronisation of the cylinders is achieved through a system of flow distribution control valves.
For the stacking system, specially-designed high lifters are needed. These lifters are supplied with an automatic head, which is always repositioned correctly for the next operation. The only manual function required is whether to select building or dismantling the stack.
The most common drive used for piggy-back covers is a chain drive, in most cases arranged on one side only. In special cases and depending on the arrangement, a rack-and-pinion drive can be used. For very heavy panels, especially on open hatch bulk carriers, an internal traction drive system has been developed. Each wheel is connected to an electric motor/gearbox system giving an extremely flexible and smooth movement.
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Services for piggy-back hatch covers
Conversions for hatch covers
MacGregor’s conversion specialists adapt hatch covers to meet new market needs and lengthen their efficient service life.
Modernisations and upgrades for hatch covers
MacGregor’s modernisation services adapt hatch covers to meet new market needs and lengthen their service life.
Other hatch covers
Folding hatch covers
MacGregor folding hatch covers are designed to optimise cargo handling operations and ensure the safety of your ship.
Hatch cover control systems
Harsh conditions on deck mean that MacGregor sources specially-designed hydraulic and electrical control system components from select suppliers.
Hatch cover load transmission
Small pads play big part in structural performance; MacGregor is able to offer a range of bearing pad options to suit every operational need.
Hatch cover sealing solutions
High quality MacGregor sealing solutions deliver a long service life, reduce maintenance costs and increase safety.
Hydraulic pivoting hatch covers
Pivoting hatch covers make the most efficient use of available deck space. They are ideal when multiple panels are not required, or when there is a short, vertical stowage space.
The MacGregor MacRack is an efficient, electric-drive system that combines drive and lift operations for side-rolling hatch covers.
Side-rolling hatch covers
MacGregor side-rolling hatch covers are commonly used on the weather decks of larger bulk carriers, such as Panamax and Capesize vessel types.
Stacking hatch covers
Stacking hatch covers for weather decks are usually all hydraulic in operation and the panels move into stowage or closure positions in a specific sequence.