Product line 01
Solar and water-heater tank heads
The volume line the plant was built on: end caps for solar water heaters, pressed one-shot on high-tonnage hydraulic presses, in stainless, enamel-grade steel and powder-coated galvanised sheet.
This is the plant's original line, and the one it grew largest on. Solar water-heater end caps have been pressed here since 2001, in volume, for the Chinese domestic industry — the work that put the presses, the tooling and the forming experience on the floor before the pressure vessel programme started. The company is a member of China's solar thermal industry association.
Built for the tank, not for the catalogue
Solar and hot-water cylinders are made in huge volumes, so the head has to be repeatable piece after piece: same diameter, same height, same neck, no spring-back surprises on the assembly line. That is what this line is set up to do.
Every head is formed in a single pressing operation on a high-tonnage digital hydraulic press, from original-pack sheet. The tooling for the common diameters stays on the floor, so your welding fixture does not need adjusting between batches.
- Diameters: Ø400 mm to Ø650 mm across the running range
- Wall thickness: 1.2 mm, 1.5 mm, 2.0 mm and 2.5 mm on the storage-tank heads
- Profile depth: 20 mm to 70 mm depending on model
- Edge and neck forms: outward flare or inward neck, to your drawing
- Openings: pressed or cut openings for pipe connections, in the positions your assembly needs
Typical solar cylinder end cap: dished profile, necked opening, straight flange for welding to the shell.
Three head families on this line
| Family | Where it goes | Diameters | Depth | Wall |
|---|---|---|---|---|
| Storage-tank inner head | The stainless head that closes the inner tank | Ø400–520 mm | 20–70 mm | 1.2–2.5 mm |
| Stainless inner head with openings | Inner tank head with the pipe openings already formed in | Ø410–650 mm | 20–40 mm | on request |
| Powder-coated outer head | The visible cap on the outside of the tank | Ø400–520 mm | 50–70 mm | galvanised sheet |
Common running diameters include 400, 410, 420, 425, 430, 446, 450, 457, 460, 465, 468, 470, 473, 476, 480, 490, 492, 500, 520 and 525 mm. If your diameter is not in the list, send it — the answer is usually a tooling check, not a refusal.
Materials and finish
Stainless inner heads
Pressed from original-pack stainless sheet (Zhangpu mill packaging, so the material has not been re-sheeted or re-bundled on the way to the press) and from enamel-grade steel sheet where the tank is vitreous-enamelled. 2B and BA finishes available.
Powder-coated outer heads
Formed from galvanised sheet, then UV-resistant polyester powder coated and cured — corrosion and weather resistance for units that sit on a roof for years. Colours to sample or to your specification.
Edge forms and weld preparation
The head itself is one piece; how it joins your shell is the part you should specify. We form both edge styles and prepare the joint so your welding fixture is not fighting the head.
Outward flare / inward neck
Both edge styles, formed to your drawing. The neck form is what lets the head sit into the tank shell with a controlled weld gap.
Joint types
Socket (insert) weld, necking weld, butt weld and flare weld — whichever your shell assembly uses.
One-shot forming
Single pressing operation, so there is no intermediate anneal, no welded blank and no seam in the head.
Model codes we run
The plant's own tooling codes for this line, in case your engineering drawings or your supplier's paperwork already reference them:
A · B-2 · C · G-2 · G-4 · GM · GY · H · HE · HY · LN · M · M12 · M14 · ML · N · R · S · SB · SH · SP · T12 · WX · X · XY · ZKL
Not sure which code is yours? Send the diameter, depth, edge form and a photo of the part and we will match it.
Solar line questions
Do you have the tooling for our size?
For the usual solar cylinders — Ø400 to Ø520 mm, depths from 20 to 70 mm — usually yes. Around twenty-six model codes are already in tooling. Send the diameter, depth, edge form and neck dimensions and we will confirm against the mould list before you spend time on a full enquiry.
Can you press the openings in the head instead of us cutting them?
Yes — openings, necks, bosses and lift pads are pressed or formed to your drawing, which saves a cutting and welding operation on your line.
What finish do you offer for exposed cylinders?
For the visible outer head: galvanised sheet with UV-resistant powder coating, in your colour. For the wetted inner head: 2B or BA stainless, plus pickling and polishing. If the head stays visible on the finished appliance, specify the appearance requirement and we will send samples.
How consistent are the dimensions between batches?
This is the whole point of the line. Tooling stays on the floor for repeat sizes, forming parameters are fixed, and every batch is measured against the same dimensional report, so your welding fixture does not need adjusting between deliveries.
Which material do you press the inner tank head from?
Stainless from original-pack mill sheet, and enamel-grade steel sheet for vitreous-enamelled tanks. The sheet goes from the mill pack to the press, so the material has not been re-sheeted or re-bundled in between — which is where a lot of forming problems actually come from.
Request a quote
Send your end-cap dimensions and we will confirm tooling and price.
Open the RFQ formsales@formedheads.com
Quotes usually go out within one working day. Drawings stay confidential.