JH21 vs. JH21DP Press Comparison (Based on Specs): Speed vs. Capability

JH21 vs. JH21DP (Based on Manufacturer Specs): A Showdown Between Speed and Capability

In Guangduan's C-frame press catalog, the JH21 and JH21DP series are often compared. Although they share a common design platform, technical data from the manufacturer reveals that these are two machine lines built for entirely different purposes. The difference lies not just in the name, but in the core specifications that determine their application and return on investment.

Based on detailed technical specification sheets, this PRESTEC article will clearly analyze the 3 biggest differences between the JH21 and JH21DP, helping you identify which machine was made for your products.

Direct Comparison of Technical Specifications (80-Ton Model Example)

To clearly see the difference, let's directly compare the specifications of two models with the same nominal force of 800kN (80 tons):

Parameter	JH21-80	JH21DP-80	Remark
Slide Stroke	140 mm	260 mm	Biggest Difference
Strokes Per Minute (SPM)	60 (fixed) / 45-85 (variable)	45-65	JH21 is significantly faster
Max Die Height	320 mm	400 mm	JH21DP fits taller dies
Throat Depth	290 mm	290 mm	Identical
Table Size	560x1000 mm	560x1000 mm	Identical

Summary of the 3 Biggest Differences

From the comparison table above, we can identify three decisive differences:

1. Slide Stroke - The Decisive Factor for Capability

This is the core difference. The JH21DP series has a slide stroke that is nearly double that of the JH21 series at the same tonnage. This transforms the JH21DP into a specialized machine for applications requiring significant travel distance, especially Deep Drawing.

2. Stamping Speed (SPM) - The Productivity Trade-Off

Because it has to travel a longer distance, the JH21DP series has a significantly lower maximum speed (SPM) compared to the JH21 series. This is a classic engineering trade-off: you gain deeper forming capability but must sacrifice production speed. The JH21 is clearly the choice for applications where productivity and part count are the priority.

3. Max Die Height - Space for Complex Tooling

With a longer stroke, the JH21DP also allows for the installation of taller dies. This is very useful when working with complex dies that have multiple levels or internal auxiliary mechanisms.

Practical Applications - When to Choose Each Model?

Choose the JH21 Press when:

• Speed and output are the priority: Your job is to stamp a high volume of parts that do not require significant drawing depth.
• Common applications: The primary jobs are piercing, blanking, bending, embossing, and shallow forming.
• The parts are relatively flat: Components like hinges, brackets, flanges, electronic parts, etc.

Choose the JH21DP Press when:

• The main application is deep drawing: This is the reason this machine series exists. Products like cans, fire extinguisher shells, sinks, pots, and motor casings require a long-stroke press.
• Parts have significant height: You need to form box-shaped or cup-shaped parts with considerable depth.
• Dies are tall and complex: You need extra vertical space to install and operate the tooling.

Conclusion: The "Sprinter" vs. The "Technical Specialist"

The data has clearly shown: the JH21 is a "sprinter," optimized for speed and efficiency in common applications. Meanwhile, the JH21DP is a "technical specialist," which, while slower, possesses superior forming capabilities for difficult jobs, especially deep drawing. The choice between the models is no longer a point of confusion, but a clear technical decision based on the geometry of your final product.