ROHM ZG/ZS, ZGU/ZSU, EG/ES - Geared scroll chucks - Manual (Page 12)

for refitting work), have to be covered with an anti--seize agent
(grease paste) in the thread area and the head contact area in
intervals of six months.
Under certain circumstances environmental influences, i. e. vibra-
tions, may loosen even tightly fastened screws. For prevention all
safety relevant screws (i. e. clamping device fastening screws,
clamping set fastening screws, or simillar) have to be checked and
-- if necessary -- refastened in regulary intervals.
13. Maintenance work
The reliability of the clamping equipment can only be ensured if
the maintenance specifications in the operating manual are strictly
observed. Please observe in particular:
-- Use the lubricant recommended in the operating instructions for
lubrication (unsuitable lubricant may reduce the chucking force by
more than 50 per cent).
-- In case of manual lubrication, please make sure that all surfaces to
be lubricated are reached (The narrow passages of the built--in
parts require a high injection pressure. For this reason, it is advisa-
ble to use a high--pressure grease gun).
-- For good distribution of the grease in manual lubrication, move the
chucking piston to its final positions several times, re--lubricate
them, and subsequently check the chucking force.
-- For good distribution of the grease when a central lubrication sy-
stem is used, the lubrication pulses should be set to the open
phase of the clamping device.
Prior to series production and between the maintenance intervals a
chucking force measuring instrument has to be used to check the
chucking force. ”It is only a regular check that ensures ideal sa-
fety”.
It is advisable to move the internal moving elements to their final
position several times after five hundred clamping actions at the
latest (Any lubricant pressed away will thus be returned to the
contact surfaces. Thus, the chucking force is retained for a longer
period of time).
14. Collision
After a collision of the clamping unit, it has to be subjected to a
professional and qualified crack detection prior to any further ope-
ration.
15. Replacing the sliding block
If top jaws are attached to the base jaw by means of a sliding
block, an original RÖHM sliding block only may be used.
III.Hazards to the environment
The operation of clamping equipment partly requires the use of various
media for lubrication, cooling, et cetera. As a rule these media are fed
to the clamping equipment through the distribution housing. The most
frequently used media are hydraulic fluid, lubricating oil or grease, and
coolant. When operating the clamping unit, these media have to be
handled with care so that they do not get on the ground and/or into the
water. Warning ! Environmental hazard !
This applies especially
Ÿ for the assembly / disassembly as residual amounts may still
be in the pipes, piston chambers and/or oil drain screws
Ÿ for porous, defective or incorrectly mounted seals
Ÿ or lubricants which escape and/or are ejected from the clam-
ping equipment during operation for design reasons
For this reason, these escaping substances should be collected and
re--used or should be disposed of according to the relevant regulations !
IV. Safety requirements on mechanically actuated clamping
equipment
1. The given clamping equipment cannot be monitored for sa
fety by means of limit switches. The operating staff shall have
to be informed of this fact correspondingly.
2. Clamping moments specified shall have to be observed by all
means. If these requirements are not observed, this may lead to
anything from unbalanced masses to the complete loss of the
clamping forces, apart from the loss of accuracy.
Safety requirements and rules and regulations for the use of manually operated chucks
Wrong Right
Projecting length of mounted work-
piece too great relative to chucked
length. Support workpiece between
centres or using a stady
Use a larger chuck
Support between centres, extend
chucking step
Chucking diameter too small
Workpiece has a casting or
forging-related taper Chuck using self-aligning
inserts
Chuck using greatest possible
chucking diameter
If cutting interrupted, reduse feed and cutting depth.
The illustrated examples do not cover all possible danger situa-
tions. It is the responsibility of the user to recognize possible sour-
ces of danger and to adopt the necessary measures.
Chucking diameter too great.
Workpiece too heavy,
chucking step too short.
Despite all precautionary measures, an element of risk
cannot be excluded.
General Remarks
-- Workpieces may only be mounted in the lathe chuck when
mounted on an adapter plate or on the machine spindle.
-- Do not measure radial run-out and axial slip until after mounting
the chuck on the machine spindle.
-- Never exert force when working with a stiff-running lathe chuck
(mounting distortion, soiling).
-- Never hit the jaws using a hammer.
-- Never use a pipe extension as a wrench.
-- Never select a chucking diameter greater than the chuck diame-
ter. Ensure that the scroll is always covered by the jaw.
-- The jaws may not project beyond the marking groove.
-- Staff entrusted with operation of the lathe chuck must read
through the operating instructions carefully before commencing
work, in particular the chapter on ”Safety remarks”.
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