Dismantling And Reassembly Of Sin- Cylinder - SMW Autoblok SIN-S Serie Manual De Instalación, Uso Y Mantenimiento

TROUBLE SHOOTING GUIDE FOR SIN- CYLINDER
The problems in the cylinder can be caused by:
A) Wear or breakage of the main seal 27 of the piston (see page 28-29-
30): in this case, replace the seal.
B) One of the pressure relief valves 15A is open, due to dirt or to the
unsetting of the springs. Try to pressurize and to relieve the pressure
a few times, by switching the power unit on and off. If the valve still
remains clogged, it is necesary to dismantle the cylinder and replace
the internal components of the valves.
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Usually, only a part of the cylinder stroke is used to drive a standard
chuck. To determine the length of the connection draw tube, remem-
ber that the front limit switch is on the cylinder and the rear one on
the chuck. If the draw tube has been wrongly designed or manufactu-
red, the cylinder will not make all the stroke requested by the chuck.
An unexplained reduction in the cylinder stroke (and in the stroke of
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the top jaws) can be due to an accidental unscrewing of the draw
tube (both from the cylinder side and from the chuck side). Screw the
draw tube properly and lock it.
20
There could be some problems in the chuck: check carefully.
21
The increase in the oil temperature is only slightly influenced by the
cylinder; it is mainly caused by the hydraulic circuit. A good power
unit shoul be able to keep the oil temperature between 35° and 65°
C, even in the worst working conditions. If the temperature is higher
than 70° C, it is recommended to increase the oil volume, by adding
an auxilliary tank or by using a system of temperature conditioning.
Check the oil level in the power unit: a reduction in the oil volume
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causes an increase in the temperature.
Insufficient lubrication of the chuck can cause noises during the
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clamping and unclamping of the component.

DISMANTLING AND REASSEMBLY OF SIN- CYLINDER

Dismantling
A) Operations to follow before removing the cylinder form the machine.
a1. Reduce the pressure to about 10 bar (while the piston is moving).
a2. Push the piston to about the half of its stroke.
a3. Cut off the pressure from the circuit and remove the feeding and drain pipes.
a4. By means of compress air, alternatively blow into the feeding fittings and
collect the oil coming out from the other fitting.
a5. Removal of the proximity bracket "19"
It is now possible to remove the complete unit, without affecting the
adjustment of the stroke control. Take care not to damage the wires and the
proximity switches fastened to the support.
a6. Remove the cylinder from the machine and put it on the bench.
B) Dismantling of the piston.
b.1 Dismantle the stroke control disk "8".
b.2 Unscrew the two drain screws "A" and "B" and remove complete with their
seals (see drawing on page 28-29-30).
b.3 Unscrew the locking screws "42" and "43" in the flange "22.
b.4 Dismantle the flange "2".
b.5 Remove the piston unit "31A", using a soft hammer from the body.
b.6 Remove the bearing cover "7" by unscrewing "37B" and using the extraction
holes. At this stage is it is possible to carry out the routine maintenance.
C) Dismantling of the hydraulic feeding manifold: to be done only in case
of proven damage to the bearings.
NOTE: this operation can be carried out with the cylinder assembled on the
machine.
c.1 Remove the bearing cover "7" by unscrewing "37B" and using the extraction
holes.
c.2 Extract the complete unit "5".
CAUTION: the bearing are transition fits, therefore use an extractor.
c.3 Unscrew "40B" and remove seal-carrier "6B", and circlip "38B".
c.4 Extract front seal "37B" and if damaged extract "46B" and "47B".
D) If it is necessary to replace the pressure relief valves, follow the
instructions listed below:
d1. It is possible to replace only the internal component of the valve "13/A"; the
housing is integral with the piston.
d2. Measure with a gauge the position of the plug of the pre-loaded spring with
regard to the edge of the housing.
d3. Unscrew the plug. (Caution: the plug is fastened with loctite).
d4 Take out the valve and replace tehe new components, inserting them in the
same position of the previous ones.
d5. Screw the plug in, as deep as before, and put some loctite to fix it properly.
The positioning of the plug is very inportant, because it gives the pre-load of
the spring, controlling the opening of the valve.
E) Should it be necessary to replace the safety valves proceed as
follows:
Dismantle the chuck and grease it with Autoblok "K67" grease.
24 Also the partial or total breakage of the draw tube or of the threads
can cause an irregular noise: in this case, replace the damaged parts.
25
If there are vibrations when the cylinder is in thrust conditions (both
when driving a chuck or a collet), this is due to the combined bending
and compressive stress on the draw tube. In this case, it is recom-
mended to insert 1 or 2 bronze bushings, to guide the draw tube onto
the I.D. of the spindle.
26 When there is too much noise between the fixed manifold ring and
the rotating part, it is possible that the bearings are going to have
a problem, due to dirty oil or wear. Replace the bearings, check the
fliters and change the oil.
Check that the cylinder and the flange turn perfectly (see mounting
27
Instructions - pos. 2).
Check that possible shocks of bars against the cylinder hole or
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other vibrations have not loosen the fixing screws of the cylinder to
the fixing flange and/or the fixing screws of the cylinder body to the
distribution flange. This could knock these parts off center. Check
carefully and center again.
29 Check that the draw tube is not unbalanced , off center, out of
traightness or too bent in thrust conditions. Reminder - The draw bar
has to be supported by means of 2 bushes in order to avoid bending
under peak pushing load.
30
Check carefully, removing the component, then the top jaws, the
chuck, the draw tube, the cylinder, the flanges, until there are no
more vibrations. Then, balance the part removed last.
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NOTE: this operation can be carried out with the cylinder assembled on the
machine.
e1. Located 2 large holes with plugs on the edge of flange "2" they are positio-
ned opposite one-another (see section E-E).
e2. Remove the two plugs "14" (See drawing).
e3. Extract the valves using a forked tool.
e4. Fit the new valves following the direction indicated on the drawing.
e5. Refit the plugs and screw them back.
Reassembly
A) Reassembly of the piston rod (part "3A" in flange "2")
a1. Locate the seal "2/2" in its place greasing it with a suitable product.
a2. Assemble the rod in flange "2" using a soft hammer
Caution: Align the max pressure valves with the slots in the flange. (Their
covers act as anti rotation pins).
B) Reassembly of the body. (part 1)
b1. Grease and fit seals "26" "29" and "30".
b2. Align body "1" with flange 2 so that letter "A" engraved on the two parts
coincide.
b3. Fit piston rod "3A" into the body 1 until the seal 27 makes contact.
b4. At this stage finish inserting piston rod "2A" and close the body "1" with
flange "2" using screws "42".
CAUTION: during this operation be careful not to damage seal "27".
b5. Lighlty tighten screws "42" and "43".
b6. Center with great care flange "2" with body "1".
b7. Fully tighten screws "42" and "43" and reassemble plugs A and B.
b8. Using a suitable tool fit seal "25" in its seat.
b9. If the collector "5B" has been dismantled remount the group according to
the instructions at point C.
b10. Reasemble cover "7".
b11. Reassemble stroke control disk "8".
C) Reassembly of the collector ring of the hydraulic rotating joint (part. "5")
c1. Fit the bearings "46B" and "47B" in their place.
c2. Assemble one ring "37B" in seal carrier "6B"
c3. Assemble cover "6B" on ring "5B" and fix it with screws "40B". Slightly
warm the assembly (+20° C over temperature).
c4. Reassemble cover "7".
D) Assembly of the cylinder on the side of the machine.
d.1 Following the assembly instructions, center the body to the rotational axis of
the machine spindle, then thighten the fixing screws.
E) Mounting of the proximity bracket.
e1. Mount the proximity bracket "19B" fixing it with screws "40B" taking care
not to damage wires or the poximity switches.
Note: see drawing of page 28-29-30
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