High-Vacuum Containment and Control
INSTRUCTION MANUAL
PMXYZ SERIES PRECISION MANIPULATORS
Version 1. 2
This manual applies to:
Model #_______________________________
Serial #______________________________
High-Vacuum Containment and Control
Preface
Congratulations! You have purchased a precision vacuum positioning device
from Nor -Cal Products. This unit is capable of many years of use with minimal
care and maintenance. This manual is a tool to aid you in obtaining this service.
We at Nor-Cal Products encourage your comments and suggestions on this
manual.
Product Description
The PMXYZ series precision manipulators are a family of aluminum units which
offer exceptional value per dollar. The PMXYZ series feature pre-loaded cross
roller X & Y stages. The 2" Z travel model with the 1.39" ID bellows has a
Micrometer drive.
The PMXYZ series are available with greater Z axis travel and larger bellows.
The PMXYZ Series instruments have a 20# equipment payload for vertical
operation. For applications which need different payloads and/or other
operational orientations, please consult the factory. See "installation" section
below for complete payload considerations.
A full compliment of options are available... many suitable for field retrofit. This
allows the unit to be modified to suit changing requirements as the role for the
manipulator changes through its life.
Unpacking
PMXYZ manipulators are shipped in custom foam-in-place packing. We have
found this the only system to provide adequate protection for shipment. The
foam is separated approximately half way inside the crate with thin blue plastic.
The bellows assembly is shipped in place protected by a cardboard or thick
paper wrap about the bellows. This wrap should be left in place until the
manipulator is fully mounted. We strongly recommend the packing be saved for
possible future shipment or equipment storage.
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Installation
******** WARNING *********
Shipping vibration can loosen screws. The user must check to verify the screw
fasteners have not backed off on the unit during shipment. This is critical for safe
operation.
***********THIS IS IMPORTANT ************
The standard PMXYZ Manipulator can be installed directly from the packing. As
usual, care should be exercised to protect the knife seal edge. The standard
units mount to a 2.75" or 6" OD flange. Proper tightening technique should be
observed whenever tightening a metal sealed flange. We recommend a small
quantity of high temperature anti -seize lubricant be used on all mounting bolts.
This is especially import ant if the unit will be subject to bake-outs.
********** WARNING *********
It is necessary, especially on longer stroke manipulators, to have an axis rod or
tube down the axis of the Z travel. This will keep the bellows from "springing" out
when the pressure is returned to atmosphere (usually when the unit is near its
most compressed mode). This function is usually satisfied by a "theta" rotation
shaft or support tube. Damage to the equipment can occur if this precaution is
not observed.
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PAYLOAD CONSIDERATIONS
The PMXYZ Series instruments have a 20# equipment payload for vertical
operation (NOT inverted). This payload is based upon the total load on the
traveling flange with the base flange securely attached to the customers
chamber, providing a strong and stable mounting. The payload center of gravity
must be within the diameter of the traveling flange OD (Normally 2.75") and
within 8" of the flange face.
Please consult the factory if your application requires:
Payload greater than 20#
Center of gravity beyond above limits
Mounting orientation other than standard vertical, such as angled, horizontal,
inverted.
If the manipulator is to be used with the Z axis horizontal, the NOW vertical
micrometer MUST be under the gradational load. The Z axis must be
UNDER the drive axis.
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Adjustments
Your PMXYZ manipulator is correctly adjusted prior to shipment. This section is
included to aid the user in making changes in these settings if he so desires.
LINEAR CROSS ROLLER BEARINGS: The linear bearings are adjustable on
thePMXYZ manipulator. There are two sets of 3 each, 8-32 set screws that apply
tension to the sets of cross rollers. To adjust, the 4 SHCSs must be loosened to
allow roller bar movement. The three set screws can then be tightened to a
uniform tension to "just load" the roller sets. The 4 SHCSs can the be tightened
to lock in the new position. This procedure can be repeated on the other
axis.MICROMETERS: Micrometer play is affected by two micrometer
adjustments.
1.Micrometer thread engagement is adjustable by removing the micrometer
handle and tightening or loosening a knurled nut on the barrel. This adjustment
normally does not need to be performed in the field.
2.The micrometer to stage coupling is adjustable via the approx. 1" diameter
knurled cylinder around the end of the micrometer spindle.
At the end of the micrometer spindle, under the 1" dia knurled cylinder, is a small,
chrome plated, dome anvil. This must be finger tight to properly load onto the
cross shaft. These are properly adjusted at the factory, and should not require
further adjustment.
When re-installing the micrometer/ micrometer bloc assemblies, the following
procedure will assure the best alignment.
1.Install and snug the two 1/4-20 SHCS. Back each screw off 1/8 to 1/4 turn.
2.Assemble knurled collar/bearing at end of micrometer spindle into receiver on
guide rod. Tighten firmly finger tight. This will align the micrometer block.
3.Tighten the two 1/4 -20 SHCS. Back off the knurled adjustment collar to a light
tension, without axial play. Test operation for smoothness.
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Lubrication
All exterior bearings, micrometers, lead screws and guide rods are lubricated
with GHT-2 high temperature lubricant. The user will need to add more lubricant
from time to time, depending on the frequency and temperature of bakeouts and
operating environment.
**************WARNING************
Additional lubricant must be added to the lead screw (or Z axis micrometer
threads) as the use and environment requires. The standard lifting mechanism is
a bronze acme thread on a burnished steel acme lead screw. This is a sliding
contact, requiring lubrication. Equipment overloading, heavy use, high
temperature bakeouts, environmental conditions, etc. can and will rem ove the
lubricant from this interface. THIS WILL CAUSE PREMATURE WEAR. If this is
continued to an extreme, the nut will fail and allow the stage to suddenly drop.
THIS SITUATION IS DANGEROUS TO EQUIPMENT AND PERSONNEL AND
MUST BE AVOIDED. Inspect this mechanism and relubricate as needed. The
Acme screw/nut mechanism should have 0.002" to 0.006" vertical (axial)
backlash maximum. If more is detected, consult the factory for suitable repair.
************** WARNING *************
This lubricant has been tested to 230 C. We recommend limiting the
temperature of the lubricant to 200 C or less.
Avoid inhalation of decomposition products formed above 300C.
This material may give off toxic gasses at elevated temperatures.
Bakeout procedure
We recommend limiting the temperature of the lubricant and the bakeout
temperature to 200 C or less.
See safety warnings under "Lubrication".
Do not run uncontrolled bakeouts or bakeouts approaching 300C
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CONVENTIONAL BAKEOUT:
SUMMARY: The PMXYZ manipulator can be baked with standard UHV bakeout
procedures.
See safety warnings under "Lubrication".
It is not necessary to remove the micrometers prior to standard bakeout. For
high temperature bake-out, or repeated bake-outs of long duration, we do
recommend micrometer removal.
MICROMETER REMOVAL:
1.Position both X & Y micrometers at mid travel. Lower the Z micrometer to it's
minimum.
2. The pre-load coupling to the stage removes by simply un-threading the
knurled collar. The same procedure is used on all X , Y and Z axis micrometers.
Check under "Adjustments" for correct instructions for re-assembly after bakeout.
3. The X & Y micrometers are bolted to the frames with two 1/4-20 SHCS each.
On large drum mics, it may be necessary to loosen a set screw and slide the
inner graduated cylinder into the micrometer outer graduated cylinder in order to
remove the socket head mounting screws. Remove each micrometer. The Z
micrometer is retained by a clamp bolt and a safety snap ring underneath the
traveling stage.
NOTE: We do not recommend stage temperatures exceed 180 degrees C
continuously and 200 degrees C intermittently. The design of the manipulator
allows room around the bellows for thermal insulation, making possible greater
bellows temperatures while not exceeding our recommendations. Under no
condition should heater tapes be used directly on a welded bellows. An electrical
short would not only create a safety hazard, but possibly destroy the vacuum
integrity of the thin bellows wall.
After bake and cool -down, re-attach micrometers.
High-Vacuum Containment and Control
We at Nor-Cal Products have a large stake in your new equipment operating up
to your expectations. If you experience difficulty with this unit, or any other
aspect of your endeavor where our experience might be of value, we want to
hear from you. We want to be part of your success.
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