When choosing equipment for the production of aluminum profiles, the most important stage – press choice. About the first three steps see. here.
Step 4 – Press layout
it – fourth step. Currently, there is a noticeable shift towards presses with a short stroke (removable ram) and the so-called compact (with front loading of the workpiece), especially in Europe. Both of these types, along with the usual layout, are shown in the figure..
Both types of presses – and short stroke, and "compact" - reduce idle time of the press, as the distance decreases, which must be passed through the stamp compared with the maximum length of the workpiece. These types of presses are much more rigid in construction., with shorter columns and less overall deflection of the front cross member. Both types require less space and fewer foundations., than ordinary presses.
Short-stroke presses reduce the stroke of the stamp by, that they move it to the side or down immediately after it leaves the container.
In a “compact” press or a press with front loading of the workpiece, the container moves back along the stamp and they both move back, to make room for loading the workpiece. The blank is loaded in front of the container and the container “swallows” it, when moving forward to the matrix.
Both of these new types of presses, understandably, more complicated than usual and require, Need to think, high production culture.
Step number 5 – Press manufacturer selection
it – fifth step. When choosing suppliers to receive specific offers for a new press, you should never justify the choice of their objective characteristics only. Most buyers take experience into account., reputation, reviews and comments from other buyers, scope of service and technical support offered.
Press suppliers are "ranked" from the most branded and most high-tech companies (and the most expensive) to companies from the so-called developing countries with a low technical level (and cheaper). "Top" presses offer high efficiency, performance and reliability, short idle cycle, latest design solutions, greater rigidity, better alignment, the best hydraulic system and latest generation computer control system. However, these "top" presses are not always the right choice for everyone.. When making a decision, the following points must be taken into account..
1) Is this press the only one in the company or are there other press, to complete an order, if this press suddenly breaks?
2) Is there money to buy "top" and expensive press?
3) Is the market ready to appreciate the benefits of higher quality products and pay for it? It depends on it, how quickly the funds will pay off, invested in a “top” press.
4) Is there a highly skilled workforce available and are you willing to pay for it? How will this affect the profitability of production?
5) Will the press remain modern and competitive for the foreseeable future, or will its technological advantages soon become obsolete?
See. separate article Selecting the extrusion press – Step 6
Step number 7 – Spare parts and technical documentation
Last step – seventh.
Spare parts for the press
Near 5 % project costs should be allocated to spare parts. Spare parts for the press must be negotiated simultaneously with the delivery of the press itself and this should be done as part of the supply contract..
Technical documentation for the press
Similarly, the supply contract should include the transfer of detailed drawings, especially press tool, which will be part of the delivery.
Источник: Al Kennedy — Seven Steps for Selecting An Extrusion Press, AND 2008