Anode Product Guide & Cathodic Protection Handbook - 2013
21Pages

MGDUFF is the UK's original marine cathodic protection In the early 1950 s Merlin Graham "Chunky" Duff, partnered by naval architects and marine engineers, developed and set the standards for ship and small craft corrosion protection. Sixty years on these are still the accepted principles and our continuous development builds on that heritage, keeping pace with modern vessel Sacrificial anodes in zinc, aluminium internationally approved MGDUFF products are specified and fitted by leading European yacht and boat builders, commercial shipping companies and ship repair yards. Experienced...

CORROSION WILL OCCUR IN ALL TYPES OF WATER WITH DRAMATIC EFFECT Metals of differing electrochemical potential when in contact with one another form Galvanic cells. The metal with a lower potential in the galvanic cell will be anodic and will corrode. The same effect can occur in areas of different electrochemical potential in a single piece of metal such as a steel plate. Any craft moored and operating in fresh, salt or estuarine water is at risk from corrosion and the effects can be costly. Corrosion on Steel & Aluminium vessels can be identified as either areas of localised pitting to the...

To determine the number and size of anodes required, match the type of vessel and select the anode suitable for the size of propeller and the type of water ■ TYPE A Vessels are single screwed with a very short length of propeller shaft exposed to the water and fitted with GRP or wooden rudders. One anode will be required to protect the propeller and shaft For Type A, B or C Vessels the following anode selection table applies FOR EACH PROPELLER ASSEMBLY FIT ONE Propeller Diameter 250mm In Salt or Brackish Water Zinc Anode Aluminium Anode Magnesium Anode Zinc Anode Aluminium Anode Magnesium...

FITTING AND BONDING SACRIFICIAL ANODES WHEN FITTING ANODES TO WOODEN OR GRP HULLED VESSELS REMEMBER: • The anode should be positioned on the outside of the hull below the waterline. • The anodes can “see” the parts to be protected. • The fixing studs are located above the bilges. • The anode location ensures the minimum run of bonding cable to the parts to be protected. • There must be reasonable internal access to the studs. • The anode should not be positioned forward of or in line with Echo Sounding Transducers or log Impellers. • Whenever an anode is fitted to a GRP or wooden hull an...

For One Year in Salt or Brackish Water fit the following Aluminium Anodes C AT H O D I C P R O T E C T I O N O F STEEL HULLED VESSELS Stud Fixed Stud Fixed Stud Fixed Area WHEN DETERMINING THE CATHODIC PROTECTION REQUIREMENTS FOR A STEEL HULLED VESSEL THE FIRST CRITERION IS THE SURFACE AREA OF STEEL HULL BELOW THE WATER LINE - THE WETTED SURFACE AREA. This is calculated by multiplying the water line length by the sum of the beam and draft i.e. LWL x (Beam+Draft). This calculation will apply to most motor cruisers and sailing boats. Stud Fixed Stud Fixed Stud Fixed Stud Fixed Stud Fixed Stud...

HULL ANODES Disc Anodes The MGDUFF disc anode range is an ideal solution for protect- ing your rudder, trim tabs and other more refined parts of your vessel from corrosion. ■ AH anode weights shown are nominal"

MGDUFF bolt on hull anodes have a variety of stud centres and hole diameters to suit all European and American designed boats. Bolt on anodes are a quick and effective way to secure anodes to your vessel, without the need for any specialist tools. MGDuff have a full range of fixing solutions to suit your vessel, please see page 18 & 19 for more information. Zinc Anode " AH anode weights shown are nominal"

HULL ANDDES

HULL ANODES MGDUFF anodes are either 'stud fixed' or 'weld on' types. The 'stud fixed' anodes with a 'steel to steel' connection are recommended for yachts and similar small craft or on craft with high quality coatings where repeated ginding off and welding on of new anodes would damage coatings. Also on vessels where anodes may be renewed underwater or where welding The 'weld on' anodes are recommended on vessels where a long life anode scheme is fitted or where the anodes may be subject to considerable abrasion, vibration or other physical disturbance. For guaranteed continuity and a 100%...

ANODE FIXINGS Anode Fixing Studs Anode Backing Sheets MGDUFF anode fixing studs (M10B & M16B range plus Stain- less Steel) feature a fully welded square plate mounting washer, which is more secure than some designs with a simple threaded washer. Anode studs are a one time fitment and as a through hull fitting, the best available should be used. Often anodes are secured incorrectly, the anode core bar should be secured and not the anode material to the structure! A backing pad is designed to stop the back of the anode from wasting away, and possibly causes the anode fixing to come loose. It...

SHAFT ANDDES The MGD range of shaft anodes are known for their superior quality, and particularly suited to vessels with high shaft speeds. Building on the integral core bar design that controls wastage, ensuring the shaft anode remains secure, the MGD range now incorporates socket head (alien bolt) stainless steel fixings with captive nuts to ensure maximum reliability. Available in a wide range of metric and imperial sizes, offering a direct fit for your propeller shaft. Top Tip - Ensure adequate clearance between the shaft anode and the shaft bracket, to allow correct cooling of the...

SHAFT ANDDES Shaft Collar Anodes Shaft Earthing Assemly - Electro Eliminator Shaft Collar Anodes are an ideal solution for boats with limited clearance between the propeller and propeller bracket. The ZSC and ZSC(T) range fits this bill, with its thin moulded section. Whether your boat is steel or GRP, to provide the best protection to the stern gear the shaft should be fitted with an MGDUFF Electro Eliminator Brush assembly. The ZSC(T) collar is one of the thinnest shaft anodes on the market, allowing boat owners with minimal shaft clearance to protect their valuable propeller and shaft....