{"id":3166,"date":"2026-10-19T10:22:59","date_gmt":"2026-10-19T08:22:59","guid":{"rendered":"https:\/\/www.taurusweb.it\/?p=3166"},"modified":"2026-10-19T10:23:01","modified_gmt":"2026-10-19T08:23:01","slug":"how-to-choose-a-scrap-shear-4-the-hydraulic-system","status":"publish","type":"post","link":"https:\/\/www.taurusweb.it\/en\/articoli\/come-scegliere-una-cesoia-da-rottame-4-limpianto-oleodinamico\/","title":{"rendered":"How to choose a scrap shear. 4 \u2014 The hydraulic system"},"content":{"rendered":"
\"-\"<\/figure>\n\n\n\n

Every manufacturer has its own view, but the use of constant-power piston pumps is beyond dispute, with the obvious exception of the service pumps.<\/p>\n\n\n\n

Always and only piston pumps<\/strong>!!!<\/p>\n\n\n\n

Beware of combinations of piston pumps and low-pressure pumps.<\/p>\n\n\n\n

Especially when the ratio between the flow rate of the piston pumps and the total flow rate is low.<\/p>\n\n\n\n

The low-pressure pumps are used for the rapid approach, after which only the piston pumps work, with a drastic drop in working speed, all the more noticeable the lower the ratio between the piston pump flow rate and the total flow rate.<\/p>\n\n\n\n

Idling, the machine seems fast, but under load it becomes slow.<\/p>\n\n\n\n

You will end up with a machine that does not produce what it promises at first sight.<\/p>\n\n\n\n

Low-pressure pumps only serve to reduce the cost of the hydraulic system for the same oil flow rate.<\/p>\n\n\n\n

For the hydraulic system, the use of hydraulic piston pumps fitted with a constant-power control device is recommended.<\/p>\n\n\n\n

With this particular type of drive, one can exploit, among other things, the possibility of reducing speed with a simultaneous proportional increase in force.<\/p>\n\n\n\n

For the same production, this makes it possible to limit installed power, with a consequent reduction in energy consumption per unit of sheared product, and to modulate the power factors involved according to the different shearing conditions.<\/p>\n\n\n\n

It is true that energy consumption must be considered, but it is also true that if you want to run, you need a powerful engine under you.<\/p>\n\n\n\n

In addition, particular attention must be paid to the filtration systems: air filters on the tank, pressure filtration on the pilot circuit, filtration on the return line and an independent filtration circuit.<\/p>\n\n\n\n

Some will object that they are too many; I say that you can never have enough filters<\/strong>, because it is better to change a filter than a pump.<\/p>\n\n\n\n

The hydraulic power unit must be \u201cclean\u201d, that is, tidy and accessible.<\/p>\n\n\n\n

Few pipes, with flexible hoses only where necessary.<\/p>\n\n\n\n

The set of valves making up the system must be mounted on distribution panels and must represent a suitable compromise between traditional spool elements and 2-way logic elements, for the sake of a sound functional balance and easy maintenance, even by non-specialist technicians.<\/p>\n\n\n\n

The preface of the book \u201cTecnica ed impiego delle valvole a cartuccia\u201d (Technology and use of cartridge valves), published by REXROTH (for the few who do not know, an important manufacturer of cartridge valves), reads: \u201cThe technique of 2-way cartridge valves (logic elements), euphorically promoted years ago as a substitute for all traditional control components, has now become solidly established as a complement to spool valve technology.\u201d<\/p>\n\n\n\n

Only a few years ago, 240 bar was considered extreme. Today, 350 bar is standard, at TAURUS, we operate at 420 bar.<\/strong>.<\/p>\n\n\n\n

The components are ready: the pumps have been for some time, and recently the valves have caught up too.<\/p>\n\n\n\n

As pressure increases, volumes decrease, everything becomes more compact and the quantity of circulating oil is reduced\u2026 and why not, so are construction and maintenance costs.<\/p>\n\n\n\n

Eng. CLAUDIO COLOMBO<\/strong><\/p>","protected":false},"excerpt":{"rendered":"

Ciascun costruttore dice la sua, ma \u00e8 insindacabile l\u2019uso di pompe a pistoni a potenza costante, a esclusione naturalmente delle pompe di servizio. Sempre e solo pompe a pistoni!!! Attenzione alle combinazioni pompe a pistoni-pompe di bassa pressione. Soprattutto quando il rapporto tra la portata delle pompe a pistoni e la portata totale \u00e8 basso. […]<\/p>\n","protected":false},"author":4,"featured_media":3167,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"class_list":["post-3166","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-articoli"],"_links":{"self":[{"href":"https:\/\/www.taurusweb.it\/en\/wp-json\/wp\/v2\/posts\/3166","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.taurusweb.it\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.taurusweb.it\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.taurusweb.it\/en\/wp-json\/wp\/v2\/users\/4"}],"replies":[{"embeddable":true,"href":"https:\/\/www.taurusweb.it\/en\/wp-json\/wp\/v2\/comments?post=3166"}],"version-history":[{"count":1,"href":"https:\/\/www.taurusweb.it\/en\/wp-json\/wp\/v2\/posts\/3166\/revisions"}],"predecessor-version":[{"id":3168,"href":"https:\/\/www.taurusweb.it\/en\/wp-json\/wp\/v2\/posts\/3166\/revisions\/3168"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.taurusweb.it\/en\/wp-json\/wp\/v2\/media\/3167"}],"wp:attachment":[{"href":"https:\/\/www.taurusweb.it\/en\/wp-json\/wp\/v2\/media?parent=3166"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.taurusweb.it\/en\/wp-json\/wp\/v2\/categories?post=3166"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.taurusweb.it\/en\/wp-json\/wp\/v2\/tags?post=3166"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}