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Vertical Eight - Spindle Semiautomatics

Increase in productivity, reduced machine tool need, floor-space savings, and simplified shop-transport routes – such are the benefits offered by the vertical turning semiautomatics.

A single semiautomatic can match nearly 20 general purpose centre lathes in output.

Each of the eight sectors into which the rotary table of these machines is divided has a spindle carrying a chuck to hold the work. In revolving around a stationary column, these sectors come to working stations provided with tool slides. To optimize the machining of work-piece of various shapes, the sequence of their passage through the working station can be changed. The working time is combined with part loading/unloading.

Complex-shape work passes through all working positions. Simple parts are machined in two or three parallel flows. In the latter instance, the eight-spindle semiautomatic acts as two three-spindle or three two-spindle machines, with the advantage of the loading and unloading stage carried out in a single zone.

The semiautomatics are designed for machining gear and flange type parts at both ends. To do this the workpiece, after being run through, is reversed and placed onto an adjoining sector for the second run.

The machines are used for turning and boring operations, and also for drilling, counterboring, reaming, and tapping holes in complex-shape parts. Special tool holders and slides allow simultaneous multitool machining and turning various profiles to a template.

The vertical arrangement of the machines is very beneficial. For example, the mass of the workpiece placed in the chuck contributes to its adequate resting on the locating surface and, hence, to reliable holding. Chips do not stay in the cutting zone and readily removed from the table surface.

All the sectors are arranged at one and the same level from the floor and are equally accessible. Each of them has a sufficient area to accommodate various fixtures, such as chucks, clamping devices, etc. To load heavy workpiece, the machine can be fitted with a hoist.

Lathes of this group are designed for machining parts which vary in complexity, and each model is available in two versions: one operating at high stock removal rates, and, the other, at high cutting speeds. The first modification features heavy removal of metal and operation under non-uniform impact loads. The second one is most efficient for machining parts from non-ferrous metals and light alloys. The two modifications differ in spindle-speed ranges, feed ranges and maximum torques.

The design provides for accurate location of workpieces in changeovers from one position to another and lasting accuracy characteristics in the main machine units.

The main users of semiautomatics are in the automobile and tractor industries.

EXERCISES

1. Using the information from the text, try to answer the following questions:

1. What are the benefits of vertical semiautomatics?

2. How are simple parts being machined?

3. What are the machines of this group used for?

4. What are the advantages of the vertical arrangement of the machines?

5. In what versions are the machines available?

6. Can you name the main users of these machines?

2.Using the text, supply synonyms for the following words:

Growth, efficiency, requirement, rotate, to supply, uptime, case, to work, to permit, design, to differ.

3. Using the text, supply anonyms for the following words:

Complex, horizontal, to decrease, rotating, downtime, loading, disadvantageous, light, uniform, ferrous, minimum.

4. Fill the blanks, using the words below:

1. Simple parts are machined in 2 or 3.......

2. A single... can match nearly 20 general-purpose center lathes in output.

3. The machining time...... with part loading.

4. The vertical arrangements of the machining is very....

5.... do not stay in the cutting zone and readily removed from the... surface.

6. To load heavy workpiece, the machine can be fitted with a....

7. The main users of the 1K282 and 1283 semiautomatics are in the... and... industries.

Automobile, tractor, table, parallel, flows, beneficial, semiautomatics, hoist, is combined, chips.