Energy Saving Electrical Drive

(ESED 4.0)

Danieli Breda is a leader among developers of metal-forming technology when dealing with efficiency in electro-hydraulic systems for Extrusion and Forging Presses.

Extruders around the world know well that the number of installed pumps is dictated by the oil required during the dead-cycle time, when a massive quantity of oil at low pressure is required.

On the other hand, during the extrusion stroke that significantly influences 80% of a total cycle time quite often only few pumps are needed: this basically means switching-off one or more pumps during the extrusion cycle and start them again immediately before dead-cycle time.

The total cycle can be divided into two different phases:

— High pressure: typically the extrusion stroke, the container butt stripping and the butt shearing: 80% of the total cycle, plus the die shearing at the press.

During this phase driver is the force: few pumps at high pressure. The maximum extrusion speed depends upon the number of pumps, rotating at 1,500 rpm.

— Low pressure: the fast movements during dead-cycle time (container: back and forward stroke; movable crosshead: back and forward stoke, die changing, billet loading in and out, dummy block lubrication….): 20% of the total cycle time.

During this phase driver is the speed: all the pumps are required, at low pressure.

Throughout the low pressure phase increasing the speed of the pumps to 2,000 rpm leads to increasing their delivery. It goes from 1,500 to 2,000 rpm (25% higher speed) which is like having one more pump for every four installed.

Optimization of the number of installed pumps improves not only the capital expenditure (the number of pumps is linked also to piping, PLC cards, cables and trays, civil works, footprint/ layout surface and each pump motor group is affecting the CapEx by approximately 80.000€ / each) but also the operating expenditure, considering the operating cost, maintenance/ spare parts and tuning operations.

ESED 4.0 targets

• Minimize the total number pumps, reducing their number to those required to reach maximum extrusion speed, when the drive is the force.
• Electro-operated movements and Variable Frequency Drive when the drive is the speed.
• Minimizing the machinery downtime as the design proposes an easy and handy maintainability of the equipment.
• Press reliability and friendly management, so that it can be operated even by personnel of average skill, not affected by complicated servomotors or high-speed pump motors maintenance.
• Competitive price and well proven/reliable technical solution, based on the experience in the forging industry for heavy-duty applications, are the other two strong points of ESED 4.0.

With ESED 4.0 are not required water cooled motors but standard heavy-duty motor, rotating at 1,500 rpm during extrusion and 2,000 rpm during dead-cycle time, fixed-delivery pumps and torque current equalizer, to reduce peaks of pressure and current.

In addition to these advantages, ESED 4.0 also reduces the operating costs for maintenance: No proportional valves, electronic cards, pilot pump or expensive refurbishing are needed. Repeatable and reliable speed control is performed electronically, making it possible to set the extrusion speed more effectively.

It is a well proven and reliable technical solution that offers both savings in power and low investment costs which demonstrates more progress for Danieli Breda in its route to become the most “green” and advanced supplier to the market.