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TECHNICAL CONCEPT OF LOADER AND

UNLOADER VALVE.

So 1stquestion in mind is what is it

Fi!st"# "et me $"ea! that "oade! and un"oade! %a"%e is %e!#

di&e!ent in !e$i'!o$atin( t#'e than s$!ew t#'e) *a# +e the same

,un$tions +ut wo!-in( '!in$i'"e is di&e!ent ,!om it)

And "oade! %a"%e is a"so te!med as inta-e %a"%e and o! an in"et

%a"%e) It ,un$tions is to !e(u"ate the ai! inta-e to the ai!

$om'!esso! 'a!t) i)e to !e(u"ate the su''"# o, ai! su$-ed u' into$om'!esso! 'a!t)

And it is one -ind o, 'neumati$ a$tuato! %a"%e whi$h o'e!ates

with a ,eed+a$- si(na" s#stem and wo!-s on a '!in$i'"e o, 'i"ot

'!essu!e whi$h is the same '!essu!e maintained +# the *PV to

o'e!ate that %a"%e)

It ,un$tions with two modes. Loadin( and un"oadin( mode)

Fo! un"oadin( mode. when the desi!ed '!essu!e is !ea$hed/ it

(oes to un"oad mode and $"oses the su''"# o, ai! inta-e to

$om'!esso! unit thus the $om'!esso! 0ust !otates +ut do not

'!odu$es an# $om'!essed ai! ,u!the!) In this wa# no mo!e ai! to

+e su$-ed in and (et $om'!essed)

ut the!e sti"" !emains the ai! inside the $om'!esso! e"ement)

This is then 'assed (ent"# th!ou(h "ow down %a"%e 2DV3)thus

(et a sound "i-e 's$$$hhhhhhh)

A(ain a question !ises in mind I, $om'!esso! e"ement is

!otatin( so how does it (ets the "u+!i$ation ,a$i"it#

The answe! is the!e is a"wa#s a sma"" ho"e $a""ed ,!ee ho"e o,

1mm in un"oade! %a"%e whi$h ne%e! $"oses $om'"ete"#) This

maintains the minimum '!essu!e to !e(u"ate the oi" 4ow ,o! the

"u+!i$ation o, $om'!esso! e"ement)

Se"e$tion o, ma$hine in te!ms o, "oad.

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The ma$hine shou"d +e se"e$ted ne$- to ne$- $a'a$it#) ut

'!a$ti$a""# i, the se"e$tion done is mo!e than the 56 'e!$ent o,

"oadin( $a'a$it# then its e7$ien$# is (ood)

How to $he$- this "oad and un"oad.

This is to +e $he$-ed in "oad !e"a# 2Read 'a!amete!3 in 'ane")

Let us unde!stand this with an e8am'"e.

I, a ma$hine is se!%i$ed with a new s'a!e AOS insta""ed/ then in

!ead 'a!amete! note down the %a"ue 916662assume3: "oad !e"a#

%a"ue

And in ne8t $han(in( time o, AOS/ the %a"ue is9 ;666)2"oad !e"a#%a"ue3)

So the di&e!en$e is 2;6666 h!s)

Then se'a!ato! use is. 2;6666 9 1666=;>6 9 ?)

Pe!missi+"e.

1) *a8 un"oads ="oad $ondition. 16nos=h!s);) ut '!a$ti$a""# it is not 'ossi+"e ,o! an# indust!# to maintain

this "imit)

E&e$t on AOS.

*o!e the "oad and un"oad $ondition) *o!e wi"" +e the hittin(

e&e$t to AOS sin$e the!e is sudden 4ow !e"eased whi$h im'a$t

the AOS)and st!ess '!odu$ed in it thus de$!easin( the AOS Li,e)

So we see +a@e '"ate is used in At"as $o'$o to (et !id ,!om

di!e$t hittin( thus !edu$es the st!ess '!odu$ed ,!om im'a$t)

ut the e&e$t is seen on E"(i=IR ma$hine)

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