Handbook-Fusion Welding Carbon

2 Equipment and Material Requirements Equipment: To do all the work covered in this chapter, you need a complete welding and cutting outfit, as described at the start of Chapter 5. At least two or three different welding heads (tips) are needed. For welding 1/ 16- in. sheet, you need one which is rated to consume about 4 cfh (cubic feet per hour) of each gas. For welding 1/ 8-in. steel, a head one or two sizes larger (consuming 6-9 cfh) is needed; this size will also be suitable for 2-in. or smaller pipe. For welding 1/4-in. plate, or 4-in. pipe, a head rated to consume 15 cfh of each gas is recommended. For bevelling plate or pipe with your torch, a cutting nozzle with cutting oxygen orifice drill size 60 or a little smaller is recommended. In addition, you need a suitable welding table (slotted cast iron or fire brick top), some C-clamps, and pliers or tongs for handling hot metal. For pipe-welding practice, two useful work-holding devices which you can make for yourself are pictured in Fig. 13-20. Materials: For practice on sheet steel, we recommend that you secure several pieces of sheet, at least 4 in. by 4 in. (10 cm by 10 cm) in size, and not thinner than 16 gauge (1/16 in. or 1.5 mm). (Sheet as thick as 1/8 in. will also be satisfactory.) For practice on plate, several pieces 6 x 9 in. (15 x 22 cm), about 1/4-in. (6 mm) thick, are suggested. For pipe welding practice, we suggest short lengths (or one length, 4-6 feet, which you can cut yourself) of standard (Schedule 40) seamless steel pipe, 2 in. to 4 in. diameter. (The larger size is preferable, if you can secure it.) You will also need a supply of steel welding rod. For sheet metal practice, 1/16-in. diameter rod is suggested. For plate and pipe welding, either 1/8-in. or 3/32-in. diameter rod will be satisfactory. Two types of steel rod which will serve your purposes are generally available. One is sometimes termed ”drawn iron” because it is more than 99% iron; it falls into A.W.S. Class RG45. (OXWELD No. 7 rod is an example of this type.) The other is usually designated as ”No. 1 HT”, contains about one per cent manganese, and falls into A.W.S. Class RG60.