Unic URW295CR, Maintenance Manual

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(3) Application of “Lock Tight”
• Apply “LOCK TIGHT” sufficiently to the threads to fill them.
Apply “LOCK TIGHT” to the component mounting o-ring (piston) at the 2nd to 3rd threads from the thread end.
(Refer to “Estimated adhesive consumption” illustrated below.)
• “LOCK TIGHT #638” is an anaerobic adhesive so that the part forced out will not cure because it is
in contact with air.In addition, sticking of “#638” to o-rings and packings may cause the rubber to be
(When it is possible to be stuck on the rubber such as o-rings and packing, apply “LOCK TIGHT” to
the threads on piston side to avoid sticking to them.)
• Try shortening the working period from the time when application of the “LOCK TIGHT” to a primed
component to completion of fitting the component.
(4) Assembly
• Tighten the component after application so that applied “LOCK TIGHT” may spread entirely to the
threads of the component.
• Since “LOCK TIGHT” forced out of the threads will not be cured, take care not the “LOCK TIGHT”
to be out during application as hydraulic oil is to be contaminated with it.
• Work quickly as the “LOCK TIGHT” in the treads starts curing.
• Curing speed differs according to temperature(ambient temperature included) of target component.
Since curing time becomes excessively longer at a temperature below 10°C, work with the component
temperature raised to 15°C or over.
(5) Curing
• This is a period while an adhesive is being joined.
Store the components still during the period.
(Recommended conditions is at an component
temperature of 15°C min. for more than 1 hour.)
Reference:
Estimated adhesive consumption when it is applied to 3 spirals of thread entirely.
Threading diameter Amount to be applied
Ｍ４０ ０．４６ｃｃ
Ｍ６０ ０．６９ｃｃ
Ｍ８０ ０．９２ｃｃ
Ｍ１００ １．１５ｃｃ
Ｍ１２０ １．３８ｃｃ
Which primer of #7649 and #7471 should be used together with “Lock Tight #638”.
Curing speed of #7469 is faster than that of #7471 but adhesion strength is lower.
If adhesion is to be carried out between metal articles, #7471 gives better result.
Type #7471 is to be used in normal case (refer to manufacturer’s comment and catalog specifications).
TELESCOPING/DERRICK CYLINDER ASS’Y, MEASURES
TOPREVENT PISTON FROM BEING LOOSENED
Chart of breakdown torque vs. curing
timeWhen using "Lock Tight #638with
primer #7471 (primer T)
（１６－３）
Ambient temperature 35℃
Curing time (Hr)
25℃
15℃
0℃
Bolt:M10×P1.5- L2S
Nut: M10×P1.5
Material:Soft steel (raw)
Breakdown torque (kgf/cm)