Heat treatment and surface finishing
What is annealing and why is it needed after deep drawing?
Answer
A deep drawn solenoid valve housing is formed from flat strip into a one-piece cup, so the sidewall is continuous parent metal and carries no longitudinal weld seam - the same part is also described as a seamless or weldless (nahtlos) housing shell. Balford draws these housings on presses from 25 t to 350 t with a maximum drawn diameter of 250 mm. A first draw on mild steel such as DC04 normally stays inside a limiting drawing ratio (LDR) of about 2.0 to 2.2, which for a 40 mm diameter cup means roughly 35 mm of depth before a redraw is needed; deeper shells take two or more draws with interstage annealing.
Sources
- Solenoid Valve Housing: Why There Is No Weld SeamA deep drawn solenoid valve housing is formed from flat strip into a one-piece cup, so the sidewall is continuous parent metal and carries no longitudinal weld seam - the same part is also described as a seamless or weldless (nahtlos) housing shell. Balford draws these housings on presses from 25 t ...
- Solenoid Valve Housing: Why There Is No Weld SeamState the wall thickness at the functional zone rather than one nominal for the whole part - the wall thins as material flows into the die. Name the material and its temper, because formability and the number of draws follow from that choice. Define the leak requirement with the test method and the ...
- What Is The Maximum Draw Ratio For Deep Drawing?Count the stages. Above three stages in 304, plan the interstage anneal before you plan the tool, because the heat treatment becomes part of the critical path Key point The maximum draw ratio is a material and tooling number. If a quotation offers a deep 304 housing at a first-draw ratio of 2.0 with...
- Deep Drawing Design Considerations for Engineers | BalfordDesign guidance Deep Drawing Design Considerations The five decisions that drive cost and feasibility are draw ratio, corner radius, wall thickness reduction, material grade and whether inter-stage annealing is needed. Send your drawing All FAQ topics 5 Decisions that drive cost Ø250 mm Maxim...
- What Is The Maximum Draw Ratio For Deep Drawing?What is the maximum draw ratio for deep drawing? About 2.0 for the first draw in deep-drawing quality mild steel such as DC04, and roughly 1.6 to 1.8 for austenitic stainless steel such as 304. Redraws are limited to about 1.2 to 1.4 for DC04 and 1.15 to 1.25 for 304. Blank thickness relative to dia...
- How To Calculate Blank Size For A Deep Drawn Cup?Does the blank size change when a part needs more than one draw? No. The blank stays the same for the whole part, because it holds all the material the finished cup will ever contain. What changes between stages is the preform diameter — the size of the partially drawn cup after each stage. Multi-st...
What an engineer still needs from you
- material and material condition (grade, temper)
- material thickness, plus the key diameter, height and wall thickness
- tolerances, burr direction and the visual acceptance standard
- annual volume - it decides whether tooling is single-hit, progressive or transfer
- surface finish, and any secondary machining, annealing or plating
Submit a drawing / RFQDFM review
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This page is an engineering answer, not a quotation and not a dimensional acceptance. It is generated from Balford's published material and held to the verified company fact sheet.