Maxwell Winches
Winches, Capstans and Windlasses for

Anchoring Solutions

15 Easy Steps to Windlass Selection

  Data in
What you will need to provide…
The process
To work with Maxwell or others to do…
Data out
The result of the information and the analysis process will be…
Choose criteria 1 Owner’s requirements for certification. If there are no formal requirements the consideration of one or more standards to be used as a guide is recommended. 2 Use rules as selected by the owner or investigate various certification bodies such as Lloyds, DNV, ABS. Alternatively consider other advisory standards such as Coastguard or other local authorities. 3 The classification body and ruling type to adopt as a guide or a requirement for the project.
Size the application 4 Gather the following information:
  • Classification body
  • Ruling type
  • Side profile
  • Yacht displacement
  • Front profile
5 The Equipment Number (EN) is a single figure relating to the physical parameters of the yacht. Use the chosen standard to determine the Equipment Number. This in turn dictates the yacht’s equipment strength and capability requirements. 6 You now have the very important Equipment Number (EN).
Size anchor and chain 7 With the Equipment Number proceed to determine the chain and anchor details. 8 Typically the Equipment Number is first used to calculate the anchor and chain size. The anchor is defined by weight for a particular type, commonly High Holding Power (HHP). The chain is defined by size, material grade (commonly U2) and length. 9 The following items are now defined:
  • Anchor type and weight
  • Chain size and grade
  • Chain length
Windlass requirements 10 Using the three key parameters
  • Anchor type and weight
  • Chain size and grade
  • Chain length
The windlass and anchoring accessories can be specified.
11 Compare the demand of the classification rule and the total load of chain and anchor and work to the most stringent one. Maxwell recommends increasing these requirements in some circumstances. 12 The following windlass criteria are now understood:
  • Static holding
  • Short term pull
  • Long term pull
Windlass selection 13 Knowing the installation specific requirements including the static holding, short term pull, long term pull and the type of power available (hydraulic or electric), the correct windlass and gear selection can be made. 14 Select the Maxwell Windlass and ancillary gear that suits the installation and functional requirements of the project whilst complying with the performance prerequisites that have been derived. 15 Now the Maxwell windlass and gear data, to meet the vessel’s requirements, is available for installation details to be finalised.