Tuesday, April 29, 2014

Why Apitong?? Selecting the Right Species for your Trailer Deck



Trailer manufacturers have used a wide range of species over the years to deck flatbeds, lowboys and other platform trailers. Before making a choice on which species to use for a wood floor, the consumer needs to understand that wood varies significantly by species – the mechanical and physical properties of a particular specie will impact the performance. 


During the 1960s, North American hardwood lumber — primarily oak, ash, beech, hickory and hard maple — were utilized extensively throughout the trailer industry. However the concern arose that domestic lumber from temperate forests was not strong enough to withstand the rigors of a platform trailer due to the weakness associated with knots and other defects. To obtain adequate trailer-grade flooring planks from domestic lumber, thorough selection was required to eliminate the defects — usually trimming boards and/or ripping them into narrow planks — which usually resulted in narrow, short-length pieces of 5' to 9'. Domestic hardwoods also have limited durability in exterior applications, and chemical treatment is necessary.


Some of these shortcomings in North American hardwood lumber were addressed when trailer manufacturers began using tropical hardwoods such as Apitong starting in the early 1970s. Because tropical climates have relatively consistent temperatures, the seasonal nature with which trees grow is mitigated and thus allows tropical species to grow at a steadier rate than those in temperate climates. Growth rings for tropical species are usually far more subtle, and grain tends to be consistently tight throughout the tree. The result is that Tropical species offer a strong lumber with reduced frequency of defects. Lumber cut from these trees can average lengths of 12' to 14', which eliminates multiple short component pieces when assembling a trailer deck.



Stength and Durability Characteristics of Typical Trailer Flooring Woods

Below is a table comparing the various types of wood that may be used in the trailer flooring industry:

SPECIES Approximate Weight per MBF at 10% MC Modulus of Rupture (psi) Modulus of Elasticity (1000 psi) Maximum Crushing Strength (psi) Side Hardness (lbs) Compression Perpendicular (psi) Shear (psi)
Purpleheart 4,800 21,300 2,420 11,380 2,060 1,910 1,830








Apitong 4,600 19,900 2,070 10,500 1,270 NA 2,070
Angelim Pedra 4,400 17,600 2,050 8,990 1,720 A 2,010
White Oak 4,200 15,200 1,780 7,440 1,360 1,070 1,360
Red Oak 3,900 14,300 1,820 6,760 1,070 1,010 1,780
Southern Yellow Pine 3,100 14,200 1,880 7,750 750 890 1,490
Douglas Fir 2,700 12,400 1,950 7,230 710 800 1,130
US Dept. of Agriculture Handbook No. 207
US Dept. of Agriculture Handbook No. 72, pp 4-24




Besides having the best strength-to-weight ratio of any species commercially used for trailer decks, Apitong (also known as Keruing) contains both a natural oleo-resin and has a silica content which is generally about 0.5%, thereby helping the wood endure outdoor elements. Other species which are also utilized due to their superior durability include Angelim Perdra / Parangelim and Purpleheart. 


With over 100 years of combined industry experience, TrailerDecking.com can help you make the right decision when it comes to selecting a specie for your trailer. We work closely with original equipment manufacturers, aftermarket repair shops, hardwood lumber distributors, fleet owners and independent owner-operators. All segments of the transportation industry rely on our knowledgeable staff for assistance in fulfilling their requirements for both original equipment and replacement parts.