Tank heads challenge forming equipment because large diameter, deep curvature, plate thickness, and edge preparation must be controlled together. The correct machine is selected from geometry and production route, not diameter alone. A shallow dished end, hemispherical head, cone, or flanged vessel end can require different force, tooling, and support.
The review should include outside diameter, crown radius, knuckle radius, straight flange height, thickness, material grade, blank condition, and allowable thinning. These values determine whether the part can start from a flat blank, needs a preform, or requires spinning combined with flanging.
A Tank head spinning machine is most suitable for rotationally symmetrical parts. The blank or preform rotates against a mandrel while rollers progressively create the contour. Large heads also need stable blank support and enough clearance as the plate changes shape.
Single-wheel equipment provides flexible path control when profiles change frequently. Double-wheel systems can distribute loads more evenly and improve stability on larger workpieces. For thick plate, the spindle, tailstock, roller slides, hydraulic system, and frame must act as one rigid structure.
Some lines separate dishing and edge flanging. Others use a dedicated Tank Head Spinning Lathe to form the body and prepare the edge in one sequence. The right arrangement depends on cycle time, size range, tooling investment, and the number of head standards.
Zhuosheng lists CNC equipment for pressure-vessel and oil-storage tank heads, as well as special machines for dish-shaped head spinning and flanging. (ZHUOSHENG)
| Production condition | Machine focus | Feature to verify |
|---|---|---|
| Frequent size changes | Programmable CNC | Recipe storage and setup |
| Large thin heads | Stable blank support | Wrinkle control |
| Thick vessel heads | Heavy-duty structure | Torque and rigidity |
| Straight flange required | Spinning plus flanging | Edge accuracy |
| Repeated production | Automated handling | Cycle consistency |
Carbon steel, stainless steel, aluminum, and special alloys have different forming limits. Strength affects torque and roller force, while elongation and work hardening influence pass design. Excessive reduction in one pass can cause thinning, scoring, wrinkles, or cracking near the knuckle.
Lubrication should reduce friction without creating problems for later welding or coating. Work-hardening alloys may need additional passes, controlled feed, or intermediate heat treatment. These points should be confirmed before tooling is approved.
Tooling may include mandrels, pressure pads, rollers, clamping fixtures, centering devices, and separate flanging tools. The mandrel profile should account for springback so the released part reaches the drawing dimensions. Roller nose radius and finish also influence local thinning and surface marks.
Handling is part of process quality. Poor loading alignment can cause eccentric forming, vibration, and uneven wall distribution. Confirm whether lifting assistance, centering references, blank supports, and safe unloading are included.
Use the planned material grade and thickness for the trial whenever possible. Measure crown height, diameter, knuckle profile, flange height, roundness, minimum wall, and surface condition. Cycle time should include loading, forming, unloading, and routine adjustment.
A qualified Tank Head Machine Supplier should translate the drawing into a written process proposal and acceptance checklist. The best machine is the system that controls thinning, leaves the edge ready for welding, and repeats the required geometry across a production batch.
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