SkyTrak 10054 Operation Manual - Manual (Page 172)

170 Model 10054 Rev 3/02
General Maintenance
Elongation
Double Extend Chains or Retract Chains:
When the original length (Figure 121, “A”) of 12.00" (305 mm) per foot
of new chain has elongated from wear to a length (“B”) of 12.36"
(313 mm), the chain should be discarded and replaced.
Single Extend Chains:
When the original length (Figure 121, “A”) of 12.00" (305 mm) per foot
of new chain has elongated from wear to a length (“B”) of 12.36"
(313 mm), the chain should be discarded and replaced.
It is important to measure the chain in the section that moves over the
sheaves because it receives the most frequent articulation. Measuring
the chain near its clevis terminals could give an inaccurate reading. The
ends of the chains, near the clevis terminal, will not have flexed as
frequently, if at all, as nearer the middle of the chains.
Double Extend Chains or Retract Chains: Measure across a span of
17 pins at the center of the extend chain. Measure from pin center to pin
center. Because the retract chain is inside the boom you will not be able
to measure the chain.
Single Extend Chains: Measure across a span of 13 pins at the center
of the extend chain. Measure from pin center to pin center. Because the
retract chain is inside the boom you will not be able to measure the
chain.
All Chains: The maximum measurement allowed is 12.36" (313 mm). If
the measurement is more than 12.36" (313 mm), the chain should be
replaced.
Figure 121
MM2120
“A”
“B”
170
Model 10054 Rev 3/02
General Main tenan ce
Elongation
Double Ex te ndChains or Retr actChai ns :
Whe nthe origin alle ngth( Figu re 121, “A” )of 12.00" (3 05m m)pe rf oot
of new chai nh asel ongated from wearto al ength (“B” )of 12.36"
(313 mm ),t he cha insh ou ld be disc arde da nd re plac ed.
Sin gle Ext end Ch ain s:
Whe nthe origin alle ngth( Figu re 121, “A” )of 12.00" (3 05m m)pe rf oot
of new chai nh asel ongated from wearto al ength (“B” )of 12.36"
(313 mm ),t he cha insh ou ld be disc arde da nd re plac ed.
Itis impo rtant tom easur et hec hain in the sec tion that mov eso ve rt he
sh ea ve sbec ause itr ece ives themos tf re quent artic ulati on.M easur in g
the cha innea ri ts cle vis termi nals coul dg ive an ina ccurate rea ding. Th e
ends ofthe chain s, near the cle vis ter mina l,wil ln oth ave fle xed as
freq uently ,if ata ll, asne arer themi ddle of the chai ns.
Double ExtendCha inso rR etr actChains: Meas ure acros sa spa no f
17 pins atthe cen tero fthe ext endc hain. Meas ure fro mpi nc enter topin
cen ter .B ecaus et her etrac tc hain is insi dethe boom you will notbe able
tome asur et he chai n.
Sin gle Ext end Ch ains: Meas ure acro ss as panof 13pin sat the center
of the ex ten dc hain .M easur ef ro mpin cent erto pin ce nter. Becau seth e
retr ac tc hain isi nside theboo my ou will notbe ab le to meas ure th e
chai n.
All Chain s: The maximum meas ureme nta llowed is 12.36" (313 mm). If
the meas urem entis more than12 .36"( 313mm ), thech ainsh ould be
rep lac ed.
Figu re 12 1
MM 2120
“A”
“B”