Y-1
Y-1
Service Data 5.5 Sheave
-2
(1 mm = 3.93701 × 10 in) Item
Standard of minor diameter (mm)
• Boom top upper • Boom top lower Only sheaves of the • Single top hoisting systems • Hook block (30 t) are listed here. (Wear of sheave groove) • Jib top
Limit of minor diameter (mm)
320
315.2
352
347.2
5.6 Inspection the hook block
Remarks Determination of limit minor diameter (When rope of nominal diameter less than 25 mm are used) Limit minor dia. = Standard minor dia. - (Nominal rope dia. × 0.3) Nominal diameter of winch rope: 16 mm
7. Perform a magnetic flaw detection test at least
[NOTICE]
once a year to check for cracks or other flaws in
The hook block is an important safety part. Follow the procedure below to inspect it and be sure to use it only under safe conditions.
the hook. Replace the hook immediately if any cracks are found. 8. As shown in the figure, punch marks are stamped
If any problems are found during inspections, repair or replace the part immediately. A change inspection must be performed when parts are replaced.
on each hook. Replace the hook when the deformation of the dimension (a) between these marks has increased by 5%.
1. The sheave groove must be smooth to avoid
9. The wear limit of the hook (b) is 3% of the whole
damaging the wire rope. Use a grinder to smooth
thickness (c).
and correct any sharp corners.
-2
(1 mm = 3.93701 × 10 in)
Hook service limits
2. Check whether or not the sheaves turn lightly. If a sheave turns heavily, the wire rope will slide
Hook capacity
Item
against the sheave, and the rope may be damaged. If a sheave turns heavily, inspect the sheave bearings, and lubricate or replace them if necessary. 3. Check that the sheave split pins and installation bolts are securely installed. 4. Check that the hook nuts are securely installed. If
30 t
4t
(mm) Dimension: a (Deformation)
200 (10)
100 (5)
(mm) Limit wear: b
3.78
1.68
(mm) Thickness: c
126
56
necessary, tighten them further or take steps to prevent their rotation.
a
5. Replace any worn or damaged hook nuts immediately.
Punch mark
6. Check that the wire rope latch functions correctly. If necessary, replace the spring.
c
b IWY01-025001E
6
WY01-2212E
