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Copper Pipe Bending Tool10/13/2021
For a guide to typical bend radii, see Table 4.1. The proper size of bender for each size tube must be used. Both annealed tube and hard drawn tube can be bent with the appropriate hand benders. Simple hand tools employing mandrels, dies, forms and fillers, or power-operated bending machines can be used.Diameter soft metal tubing up to 90 degrees. The tool bends 1/4 in., 5/16 in. Bender recovered after a few bends.Husky's Tube Bending Tool provides precise tube bending without kinking or flattening. Editor’ Note: This article is based on the Tube Bending 101 FabCast, facilitated by the Fabricators & Manufacturers Association International (FMA) and presented by Danie Jacobs, president of i-Fab LLC.Also for copper thin-walled heating tube according to DIN EN 1057 and for tubes of pressfitting systems.
Copper Pipe Bending Tool Trial And ErrorFundamental TermsBending starts with knowing the properties of the tube or pipe you’re working with. The technology used to bend tubular workpieces has evolved significantly, but all the mechanical magic can’t alter physics.Regardless of whether you’re working with tube or pipe, and regardless of the bending process, making the perfect bend boils down to just four factors: the material, machine, tooling, and lubrication. But in reality, the basic principles have remained the same for decades. Made of lightweight, die-cast aluminum, it boasts a powder-coated finish that resists corrosion.Tube Bender Set Copper Pipe Tubing Bending Tool Kit 90-Degree Multi Size Bending Device Includes Tube Cutter with Carry Box, for 1/4,5/16, 3/8, Inch.Many call tube bending a black art, a mysterious process with unavoidable trial and error. ![]() In tube bending, the quality, size, and consistency of that weld seam matter. Copper undergoes less radial growth than steel, which has less springback than stainless steel.Although some are seamless, most tubes are produced with a longitudinal weld. Generally speaking, the harder the tube and the smaller the bend’s centerline radius, the greater the springback and resulting radial growth. More specifically, it’s the distance between two tangent points, where a straight section begins to curve and the bend starts or finishes.Like in press brake forming, tubes experience springback after bending, producing a bend that undergoes radial growth. The distance between bends (DBB) is just what it says. Specialty tube bending processes abound, some old and some new. That’s because as the outside stretches, the inside radius compresses and at a certain point starts to wrinkle.Like any other manufacturing technology, the application requirements drive the fabrication method of choice. Some ovality is acceptable for certain applications, but unacceptable for precision work. This causes the outside surface of the bend to cave in, causing ovality, or a distortion of the cross section from its original round shape. That creates problems if you want to create the perfect bend.Elongation occurs during bending, and the outside radius stretches (causing wall thinning), which the material resists. This prevents wrinkling and forces the outside surface of the bend inward, producing a concave surface and preventing excessive stretching on the outside of the bend.This process is by far the least expensive way to bend tube and pipe, but it’s not as controllable as other methods. This method is popular in square tubing applications, for which many design the ram tool so that it deliberately compresses and slightly deforms the inside bend radius (see Figure 4). You generally can achieve a centerline radius (CLR) that’s three to four times the workpiece OD.The workpiece ID isn’t supported, and a substantial amount of stretching occurs on the outside of the bend. One of the oldest and simplest tube bending methods, it uses a hydraulically driven ram that forces a tube against rollers or pivot blocks. Ram-type BendingVisit any muffler shop and you’ll probably see a ram-style bender (see Figure 3). If a workpiece has a one-diameter pitch and a large radius, the operator can lift the tube after one revolution to produce a continuous coil. For this system, the tube feeds between an upper and lower roll, while on either side two adjustable guides move to produce the desired bend angle.Many use roll bending to produce spirals. On some, the top roll moves up and down to produce the desired angle on others, the two bottom rolls move and the top roll remains stationary (see Figure 5).Another machine type is the two-roll, pinch-style roll bender. Which rolls move where depends on the machine. The rolls move to produce specific, usually very large radii. Roll BendingCommonly used for large workpieces in construction, roll bending generally entails three rolls positioned in a pyramid, oriented either vertically or, for larger sections, horizontally. Heavensword extreme ffxivThe roller effectively “compresses” the tube against the central bend die. The system clamps the workpiece just behind the rear tangent point. Compression BendingCompression bending uses a roller or compression die (sometimes called a follow block) to bend the workpiece around a stationary bend die ( Figure 6). Balloon pump basics for nursesIf you see a towel bar with two identical bends on each side, it was probably formed with compression bending (see Figure 7). This method is used mostly to produce household and commercial products. It’s not recommended for workpieces with a CLR less than three times the tube diameter. This method works well for tubes bent to a CLR that’s at least three times the tube OD.The bend’s outside surface may flatten slightly because the tube ID is not supported. Copper Pipe Bending Tool Series Of ArticulatingGood ToolingTo achieve the perfect bend, you need a good tooling setup, and nowhere is this more critical than in rotary draw bending. All these elements effectively control both the tube ID and OD throughout bending. The pressure die can be stationary it can follow the workpiece, sliding on rollers at the same rate the workpiece is being drawn into the bend or it can be “boosted,” pushed with hydraulics or (more common today) electrical servomotors, further minimizing wall thinning. Other critical dimensionsAre the wall thickness (which thickens on the inside radius and thins on the outside radius) and outside diameter.The pressure die (also called a pressure slide) supports the outside radius during bending. Rotary draw bending supports the flow of the material during bending using a mandrel in the tube ID and precision tooling on the outside (see Figure 8).A rotary draw setup entails a pressure die that holds the straight section (sometimes called the tangent) of the tube a clamp die that rotates the workpiece around a round bend die a mandrel, sometimes with a series of articulating balls on the end to support the tube interior around the bend and a wiper die that contacts the workpiece just before the tangent point of the inside radius, wiping against the material to prevent wrinkles that can form on the bend’s inside radius.A bend angle in tube bending usually is calculated from the outside—the complementary bend angle. This process gives you maximum control over wall thinning and ovality. Occasionally some technicians shorten this length to two times the tube OD, but this isn’t usually recommended. The wiper die can wear over time, so for some jobs, it is good practice to keep a spare wiper die available.As for the clamping die, its length should be three times the tube diameter. It should be sharp to the touch. The condition of the wiper die’s contact point is also critical. The die should be angled slightly (a little off parallel with the tube) so that its end contacts the tube just before the inside radius tangent point—a transition that’s the workpiece’s weakest point during bending. An inconsistent weld bead protruding into the tube’s inside or outside surface will wreak havoc on the mandrel, pressure die, and wiper die.Regarding the wiper die, its position is critical (see Figure 10).
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