23 Hooked on SER VICE rope is either left or right Rope lay is further c l assified as either regular or lang In a regular lay rope the wires in the strands are laid in the opposite direction as the strands in the rope In a lang lay rope the wires in the strands are laid in the same direction as t he strands in the rope Regular and lang lay ropes are easily identified by the a ppearance of the outer wires with respect to the rope axis as sho w n by the examples to the right Right regular and right lang are the most common types of lay in use Each possesses unique characteristics important to proper selection Wire rope can be manufactured with five types of lay Regular lay ropes are generally more stable and more resistant to crushing Lang lay ropes are significantly supe rior in fa tigue and abrasion resistance Ho wever lang lay ropes are more susceptible to crushing and require good winding conditions They are also extremely prone to rota te under load they must never be used unless both ends are restrained Alterna te lay rope combines the best fea tures of regular and lang lay ropes It offers the advanta g es of both constructions while minimizing the disadvanta g es This construction is ideal where high bending stresses fa t igue are combined with high ropetoshea v e pressure crushing for example as a pplied to boom hoist rope Rotation Resistant Wir e Ropes Combina tions of lays are sometimes emplo yed to achieve rota tion resistant properties In this 19 x 7 rope as well as in 8 x 19 IWRC Rota tion Resistant rope the extreme rota tional property of lang lay rope is used in the core to coun teract the tendenc y of the outer regular lay strands to rota te in the opposite direction Selection Wire rope selection is a highly specialized art and science Only extensive experience can qualify the selector to choose the proper rope for a specific a pplica t ion Lubrication Wire ropes are actually intrica te machines comprised of man y components which require lubrica t ion During manu facture ropes receive lubrica t ion the kind and amount depend upon the rope size type and anticipa ted use This lubrica t ion protects a g ainst corrosion and enhances per formance It is not possible to permanently lubrica te ropes Most rope a pplica t ions will require supplementar y lubrica t ion Corr osion A large number of wire ropes fail because of corrosion which may be either external internal or both Normally corrosion tak es place because of acid or alkaline a t mosphere which is due to sea air industrial fumes or other conditions In most cases corrosion cannot be completely elim ina ted but it can be resisted by c l eaning and lubrica t ing rope or by using galvanized ropes In short a rope which would ha ve adequa te resist ance to corrosive factors should be selected Though there would be a number of other factors which would influence the life o f a rope the above factors are generally important In certain cases these properties are contradictor y F o r example increasing the diame ter of the outer wires of a rope increases resistance to abrasion but decreases resistance to bending fatigue It is therefore ver y importan t tha t the ultima te selection of rope must be a most acceptable compromise Each of the desirable char acteristics should be attained to the maximu m degree possible without excessive sacrifice of the other required properties Right Regular Lay Strands are laid to the right and wires a ppear in line with the rope Right Lang Lay Strands are laid to the right but the wires a ppear to make an angle with the rope Left Regular Lay Strands are laid to the left and wires a ppear in line with the rope Left Lang Lay Strands are laid to the left but wires a ppear to make an angle with the rope Alterna te Lay Alterna ting right regular and right lang lay strands