Start with the complete description
A request for two-inch tubing is a starting point, but it leaves several questions open. Is the tubing square or round? What wall thickness do you need? How long should each piece be, and how many pieces are on the list? Writing out the full description helps the supplier identify the material and helps you compare prices for the same item.
Read square and rectangular dimensions from the outside
Square and rectangular structural tubing is commonly described by its outside dimensions and wall thickness. For example, a description of 2 × 2 × 0.120 inches identifies a square section with nominal two-inch outside dimensions and a nominal 0.120-inch wall. A rectangular description such as 2 × 3 × 0.120 inches identifies two different outside dimensions. State the units and wall thickness explicitly when requesting a quote. These examples explain the notation; they are not stock or suitability recommendations.
Keep wall thickness separate from outside size
Two pieces can have the same outside dimensions and different wall thicknesses. They will not have the same weight or section properties. They may also behave differently during fabrication. If a drawing specifies a decimal wall thickness, pass that value along. When material is described by gauge, confirm the corresponding thickness rather than treating the gauge label as a complete specification.
Do not assume tubing and pipe names match
Round structural tubing is generally described by outside diameter and wall thickness. Standard pipe often uses nominal pipe size and a schedule designation. A nominal pipe size is not necessarily its measured outside diameter. When replacing a part or fitting one piece inside another, provide actual measurements and the intended fit. Nominal dimensions alone do not guarantee that two pieces will telescope together; tolerances, weld seams, and corner shapes can affect clearance.
Add length quantity and specification
Include the required piece length and quantity as well as the cross section. If you need cut pieces, distinguish those finished lengths from the stock lengths you are asking to buy, and ask whether cutting is available. Pass along any material grade or ASTM specification on the plans. Size alone does not establish that a piece is suitable for a structural application. Keep specified materials and any proposed substitutions with the person responsible for the design.
Use a description the supplier can quote
A clear inquiry might read: Please quote six pieces of square tubing, 2 × 2 inches outside dimensions, 0.120-inch nominal wall, each 20 feet long. Please confirm the available specification and stock length. That wording gives the supplier concrete details to check. It does not assume the example size is available or appropriate for your project. A complete material list makes those questions easier to resolve before you buy. Have your tubing dimensions and quantities ready? Contact The Railroad Yard at 405-377-8763 or visit our Pipe and Steel page to discuss your material list.
Questions about your material list? Pipe and Steel | New or Used Pipe for Fencing
