You’re basically choosing along four axes: (1) where you bend (site vs shop), (2) power availability, (3) repeatability/volume, and (4) tube range + bend complexity. Here’s how the machine categories map to those needs, and where each of your linked pages fits.

1) If you often work on-site with no power and want “controlled force”: Hydraulic pressure-bending assembly machines

These are ideal when you want the power of hydraulics but still keep things installation-friendly (including jobs where electricity is limited). The pressure-bending overview also highlights variants depending on your application: manual vs electric, very large bend angles, and even specialized pipeline/PEHD work. Hydraulic assembly machines using the pressure bending

What stands out in that category

• Manual machines with a sliding clamp/yoke pair: strong for smaller bending tasks where operator control matters, and explicitly positioned as useful for installations where electrical power is not available.
• Electric versions: add automation and consistency for more repetitive work.
• 180° linkage machines: for high bend angles up to 180° in more industrial contexts. 
• PEHD pipeline-focused machines: when coating integrity matters and the bending system is designed around that constraint.

When you pick this:

You’re bending in the field, want hydraulic leverage, and you’re not primarily chasing fast “production cycles”—you’re chasing reliable bends under real installation conditions.

2) If your priority is maximum portability (service/maintenance/construction): Mechanical tube bending machines for assembly (portable)

This bucket is the “bring it to the job” category. The page breaks it down nicely into purely mechanical, hydraulic, battery hydraulic, and electro-hydraulic—basically a spectrum from simplest to most capable.
Mechanical tube bending machines for assembly

How to choose inside this category

• Ultra-portable mechanical (example: P/22A): positioned as extremely light and fast (noted at ~1.15 kg) for mobile use.
• Portable hydraulic (example: OB/85S): described as very compact, with “enormous power” and a long piston stroke for a larger working range—great when hand force isn’t enough.
• Battery-powered hydraulic (example: OB85/SB): explicitly meant for soft-annealed copper up to 22 mm and multilayer up to 32 mm, and designed for unpowered/hard-to-reach areas. 
• Electro-hydraulic (example: OB/2003 E): expands tube compatibility (incl. copper/stainless/bonderized steel up to 22 mm, multilayer up to 50 mm) and is aimed at professional use where you want efficiency plus broad coverage.

When you pick this:

If 60–80% of your bending is on-site, this is usually the best “first buy”. You can match the drive type to your reality: manual/mechanical for simplicity, hydraulic for force, battery for no-power environments, electro-hydraulic when you want a wider tube range with less effort.

3) If you do mixed site + workshop work and want repeatable angles without jumping to full automation: Electric (optionally digital) workshop & assembly machines

This category bridges “portable enough” and “workshop accurate.” The UNI series here is described with electric drives, controlled bend angles up to 180°, and automation features like automatic return and electric braking—very useful when you’re doing repeat jobs.
Mechanical tube bending machines for workshops and assembly

Key decision point: do you need stored programs?

• UNI models are described with optional digital control using a multilingual microprocessor that can store up to 50 bending programs with up to 9 sequential angles—that’s exactly what you want if you repeatedly make multi-bend parts and don’t want to re-dial angles each time.
• There’s also a model described for tight radii and delicate/thin tubes (UNI 60 AI) with an interchangeable/reduced shaft and mention of bending radii under 30 mm using special formers/guides.

When you pick this:

You’re doing enough repeat work that “consistent angles” starts costing time/money, but you’re not yet at the point where a CNC cell is justified.

4) If it’s primarily workshop production and you want more speed + heavier capability: Mechanical tube bending machines for workshops (digital / combi)

This page leans more “shop floor”: heavier machines, higher throughput, and specialized functions (like combining bending + ring rolling).
Mechanical tube bending machines for workshops

Examples of what changes here

• UNI 30 SPEED: noted for a max bending capacity around 1” gas pipe (33.7 mm) and a claim of significantly reduced bend time vs a standard UNI 60 (70% faster). Also includes digital storage (up to 50 programs / 9 sequential angles).
• UNI 60 COMBI: positioned as a combi machine that works without a mandrel and can do tube bending plus ring rolling for tubes/profiles/plates, again with digital programming (50 programs / 9 sequential angles).

When you pick this:

Your workshop is doing frequent bending work, you want repeatability + speed, and you might benefit from multi-function capability (like ring rolling) rather than only bending.

5) If you’re heading toward high volume, complex parts, minimal scrap, integration: Automated / CNC tube bending machines

This is the “when it becomes production engineering” step: CNC control, integration with CAD/robotics, automated loading/unloading, and model ranges based on diameter class.
Automated tube bending machines

How the automated page frames it

• Small diameter automation: e.g., Herber 155s / 150RL mentioned for roughly Ø 4–25 mm with automation and integration.
• Medium–large: CNC models described across ~Ø 26–57 mm class, with automation options and features like simulation/online connection/material recognition depending on model.
• Large diameter: machines described with high torque (e.g., 18,000–24,000 Nm) and tube OD ranges up to around Ø 110 mm, aimed at automated production lines.

When you pick this:

When your bottleneck becomes throughput, scrap rate, and process stability, and you can actually keep an automated system busy enough to justify it.

A “start here, upgrade later” path for your exact situation

Given what you wrote (mostly on-site + sometimes no power + some repeat jobs), a practical progression is:

Start with a portable assembly machine aligned with your tube mix and power reality

• If “no power” is common and your typical range is copper/multilayer: the battery hydraulic approach is the most direct fit.
• If you want broader capability and do have power sometimes: electro-hydraulic expands tube coverage and reduces effort.

Add an electric (ideally digital) workshop & assembly machine once repeat jobs become frequent

• Digital storage (50 programs / 9 sequential angles) is the “repeatability unlock”.

Move up to a workshop-focused digital/combi machine when speed and versatility matter in the shop

• Especially if you want faster cycles or multi-function tasks like ring rolling.

Go automated/CNC only when volume + complexity justify it

• That’s when integration and automation actually pay back.