Mechanical Plating and Mechanical Galvanizing have long been accepted 
  as  processes  that  are free from hydrogen embrittlement and processes 
  that  offer  superior  economics for heavier metal deposits,  furnishing an
  excellent  alternative  to  hot-dip  galvanizing for small parts and threaded
  fasteners, particularly on high-strength bolts.  Today, the most important 
  new   advance   in   mechanical    deposition  technology   in  thirty  years 
  provides  better  quality  and  lower  costs.

      
 
        HyperFlowTM

This    new   technology   from   Plating   Systems  &  Technologies,  the  art  and  science   of  mechanical 
plating,  offers these  important  features, advantages, 
and  benefits:

The   PS&T   HyperFlow  Process Provides  The Smoothest  Mechanical  Deposit Ever  Produced

In  traditional mechanical deposition processes,  powdered metal is charged to 
the  plating  barrel  in  relatively   small increments. Once this powdered plating
metal becomes mixed with the glass beads, parts,  acidic chemicals, and water, 
there  is  a  tendency  for  the  metal  particles to form agglomerates as the acid
continually etches their surfaces in order to provide a clean surface to enhance
deposition.  As   these agglomerates  are plated, they produce a rough deposit.

This  phenomenon,  by   the  way,  is  partially  dependent upon pH - so that the
older  (citric acid based) chemistry  generally gave smoother deposits than the
strong  acid  (sulfuric  acid  and  hydrochloric  acid)   chemistry  of  more recent
vintage. The  fine  beads  will  partially  break up these agglomerates,  giving a
smoother  coating.  However,  the tendency  of  the process to produce a rough 
deposit  is  not  completely  eliminated  by  the  fine beads.

In   PS&T’s    revolutionary   new  HyperFlow  Process,   each  metal  particle  is  
completely  dispersed  in  the  slurry  by  PS&T’s   proprietary Carrier chemistry
before  it is charged to the barrel.  For that reason,  the HyperFlow Process has 
shown  the  ability  to  produce  a  remarkably  smooth  and  uniform  deposit.


HyperFlow’s   Reduced   Thickness   Variability Means   Superior   Quality   and   Improved 
Economics

Both  high  and  low   coating weight (or coating thicknesses) give rise to quality
deficiencies.  The primary purpose of Mechanical Plating/Mechanical Galvan-
izing is to provide corrosion protection. The duration of the corrosion protection 
obtained  is  dependent  on  coating  weight.  Low   coating  weights  give rise to 
premature failure and to low (and inconsistent) salt spray results.  High coating 
weights  (or high coating thicknesses) are also deleterious.   Excessive coating
weights  can  lead  to  poorly  consolidated  deposits and difficulties with thread 
gaging.  The  PS&T  HyperFlow  Process provides plating metal to the  plating
barrel   at  a  more  uniform  rate  than  has   ever  been  possible  in traditional 
mechanical  deposition  processes,  resulting  in the smoothest,  most uniform 
mechanical  deposits  ever  achieved.

Improvement  in  coating   weight  or  coating  thickness variability  also makes
mechanical   deposition   less   expensive.    Here  are  comparative examples
contrasting  parts  plated  to  a  minimum  thickness  of   4.00   tenths  of  a mil 
(0.0004").

    

                                            

   Consider    a   traditional  mechanical   plating   pro- cess,     with   a    standard
deviation of  1.00  tenth of 
a   mil  (a   Pearson’s  Var- iability of 25%). In order to assure  that  at  least  95% of  the  parts meet at least  the   minimum  thickness,  a     statistically   proficient plater  would need to plate these  parts to an average
thickness   of  6.79 tenths.

 

Compare the same parts
plated     in    the    PS&T
HyperFlow process.Here, 
the   plater,   through  the
use   of   improved  tech-
nology,is able to achieve  
a  standard  deviation  of   
0.40mils   (a    Pearson’s 
Variability  of  10%).   To 
achieve    a     minimum
thickness  of  4.00 tenths
on    95%   of    the  parts
plated,  this  plater  need
only   target  an  average
thickness  of  4.79 tenths.
This  results in  a metal
savings  of  nearly 30%
(compared  with traditi-
onal processing).These
savings   accrue   to   the 
plater  not only as  direct 
costs (such as materials) 
but   also   indirectly   as 
cost   savings   in  waste 
treatment.


                      


What  is  Cpk   and  Why  Is  It  Important?

The  statistical  measure   Cpk  is  an index indicating the extent to which a pro-
cess is in control.  Those statistically inclined may infer from the formulae that 
Cpk   is  essentially  a  measure  of   whether  the  process  can  or  cannot stay 
within  a  3s  range  which  is  to  say   whether  or not at least 99.87% of the test
results  are  within the prescribed specification.  (A process may also have low  
(or  unacceptable)  Cpk if  the  process is not centered within the specification.)

How  Does  HyperFlow   Improve  Cpk?

It   is   well  known   to  mechanical  platers  and  mechanical   galvanizers  that
increasing  the  number  of  separate   metal additions to the plating barrel  will 
decrease  the part-to-part variability, and  thereby improve the control over  the 
process  as  measured  by   Cpk.     The  PS&T  Hyperflow  Process  takes  this 
approach  to  its  natural  conclusion -  essentially  an infinite number of metal  
additions.  The markedly smoother HyperFlow deposit also reduces  the (test)  
variability  of  the  thickness  readings.

How Much Does HyperFlow Reduce Variability?

The  fairest   way  to   measure  part-to-part  variability  is  through  the   use  of 
"Pearson's  Variability"   (occasionally   referred    to   as   simply  'Variability')  
which is the standard deviation divided by the mean (or x-bar over s or s); this 
'levels  the  playing  field'  as  thicknesses  increase.

Historically  Pearson's  Variabilities  for   Mechanical  Plating and Mechanical 
Galvanizing  have  been  in the range of 10% to 50% and usually in the range
from  25%  to  45%.  The  use  of  the  PS&T   Brand  HyperFlow  Process has 
allowed  metal  finishers  to  achieve  variabilities  as   low  as 8%. (The actual
results  will,   of  course,   vary  based   on  part  type,   processing  conditions, 
thickness  testing   equipment  and  thickness  testing  protocols.)

Based  on  considerable history in evaluating Mechanical Plating and Mech-
anical  Galvanizing,  representative  comparative  examples  are  as  follows:

   Conventional Process HyperFlow TM Process

Specification Limits
Mean Thickness:
Standard Deviation:
Pearson's Variability
95% range
Total % out of spec
Cpk		 0.00050 +/- 0.00015 inches
0.00050 inches (5 "tenths")
0.000125 inches (1.25 "tenths")
25%
0.000255" - 0.000745"
23.02%
0.40 (not in control)		 0.00050 +/- 0.00015 inches
0.00050 inches (5 "tenths") 
0.00005 inches (0.5 "tenths")
10%
0.000402" - 0.000598"
0.28%
1.00 (in control)

 

HyperFlow’s Features, Advantages and Benefits

n A  Smoother  Coating.   With  the  PS&T   HyperFlow  Process,    the  metal 
particles are dispersed in a carrier liquid, eliminating dependence on operator
technique,  eliminating  reliance  on the fine beads, instead relying on PS&T’s 
improved  chemistry,  thus  providing  a  much  smoother  coating.

n Less  Part-to-Part  Variability   in  Coating  Thickness.      It  is  universally 
acknowledged  that  increasing  the  number of separate metal additions to the
plating  barrel  will  reduce  the  part-to-part   variability.  The  PS&T  HyperFlow 
Process  achieves  the  ultimate  improvement  by  essentially increasing the  
number  of  separate  metal  additions  to  a  nearly  infinite  number.

n Improved Industrial Hygiene.  The  HyperFlow metal slurry system greatly 
reduces  operator  exposure  to  dusty  airborne  plating  metals.

n Improved Thread Profiles - Both Internal And External.  In the HyperFlow 
Process,   each  particle  of  plating  metal  is completely dispersed before it is 
charge  to  the  plating  barrel.  Therefore,  the  resulting  thread profile is much 
more  uniform and  much  smoother.  Internal  threads  have  sometimes been
a  problem  for mechanical platers.  With external threads,  the plater may rely 
on the mechanical  energy  imparted  by  the  parts  and the media to break up
agglomerates.  This  is  not  always the case when plating  internally  threaded  
fasteners;   occasionally  there  are   aggregates  of  coating in the thread roots.  
These   are   the   result   of  depositing  agglomerates  of  plating  metal.   This 
problem  has  occasionally  manifested  itself  in  driveability  problems.

n Improved Metal Utilization.  Thickness requirements are usually stated with
a  minimum  requirement that must be met by a large percentage of  the parts. 
Because  the  coating  thickness  variability has been minimized,  this require-
ment  is  achieved  with  less   plating  metal.

n Better Consolidation.  "Consolidation"   is  the  term  used  by  Mechanical 
Platers   and   Mechanical   Galvanizers  to  refer  to  the essential  process  of 
mechanical  deposition -  the   flattening   and "cold welding"  of  particles of  a soft  metal  to  the  substrate.  By  assuring that each particle is separately de- posited,  the  consolidation  is  significantly  improved.

n More Consistent Salt Spray Results.  More  uniform  coating weights and 
coating   thicknesses   obviously   translate  into  more  consistent  salt  spray 
results.

n Reduced  Waste Treatment Costs.    With   less   metal   powder   required 
because  of  improved  metal  utilization,  less metal goes into the waste treat-
ment  system,  resulting  in  lower  costs.

n Brighter   Chromates.   Chromate   coatings   are   thin   and   transparent. Because  the  underlying  deposit  is  smoother  and  brighter,   the chromate 
coating is also smoother  and  brighter.

n Less Expensive.   Improved  metal  utilization  coupled  with  the  resulting lower  waste treatment costs and fewer rejects means that this new, improved process is significantly less expensive than older processes.

n Exceptionally  Consistent  Mixed  Metal  Deposits.     Many mechanical  
deposits  utilize  zinc  with  admixtures of tin to provide lubricity and to reduce 
white  corrosion  products.    For   many   platers,   achieving  a  uniform  con-
sistency using dry mixing processes has been difficult. PS&T’s revolutionary  new  HyperFlow   Process,   with its uniform liquid mixture, assures platers of  
consistent  metal  ratios.

How The PS&T Brand HyperFlow Process Works

In   traditional   Mechanical  Plating/Mechanical   Galvanizing  systems,   the 
plating   operator  adds   dry  metal  powders  to  the  plating  barrel.   This  is considered  a  critical  part  of  the  process,   and  the  operator  is  generally instructed to carefully disperse the metal into the supernatant process liquid.

In  the  PS&T  HyperFlow  Process,  the plating metal is first mixed with water 
and a  proprietary ‘Carrier’  to produce a slurry. This slurry is then  introduced  into  the  plating  barrel,  either  manually or through the use of  a pump.  The pump  can  be  operated manually or under the control of a digital processor 
or   personal  computer.   The  proprietary  chemistry  of  PS&T’s  HyperFlow 
Carrier   prevents  the  plating  metal  from  settling  and  otherwise  helps  to  
produce a smooth,  uniform deposit.  The concentration of plating metal can  
be as low  as one pound  per  gallon  or  as  high as  ten  pounds  per gallon.

Existing  Processes  Easily  Upgraded  to  HyperFlow

n Level One.   For  the  simplest  and  least  expensive  adaptation  of  the HyperFlow   technology  to  mechanical  deposition  processes,  all  that  is 
needed  is a tank and an agitator.  The correctly formulated slurry  is made 
from  metal  powder,   PS&T   Brand  HyperFlow  Carrier,  and  water.    The operator,  instead  of  making  powdered additions to  the  barrel,  adds  the 
slurry in small incremental amounts. The cost for this level of  implement-
ation  is  less  than  a  few  hundred  dollars.

n Level Two.  The   next  step up from  the ‘Level One’ is to add a pump to 
the tank, and  pump  the slurry  over  a  fifteen  or twenty minute period into 
the plating  barrel.  This   frees  the  operator  to  perform  other  tasks while 
the     metal   is   being  added   to   the   barrel,    and  the  cost - under  two 
thousand  dollars -  is   quickly  recoverable  from reduced  labor  costs.

The   next  step up from  the ‘Level One’ is to add a pump to 
the tank, and  pump  the slurry  over  a  fifteen  or twenty minute period into 
the plating  barrel.  This   frees  the  operator  to  perform  other  tasks while 
the     metal   is   being  added   to   the   barrel,    and  the  cost - under  two 
thousand  dollars -  is   quickly  recoverable  from reduced  labor  costs.

n Level Three.   Level Three.   The entire tank,  agitator, and pump configuration can be placed  on

n Level  Level  Four.    The   next  step  up  is  to  place  the  HyperFlow  Process 
under  the control of  a  microprocessor  or  digital process controller.  This 
controller  can  then  control  the  addition  of   the  other  chemicals  to  the process -  cleaning  agents,  coppering  agents, and  promoters.  This  step  
can be implemented  for  about  thirty  to  forty  thousand   dollars. 

n Level Five.   The  ultimate  process  is  to  use  a  personal  computer  to 
control  the addition of  all   the chemicals and metals through software and hardware  interfaces  with the pumps and scale(s).  PS&T’s studies indicate 
that  this can be done for less than  fifty  thousand  dollars,  much  of  which  
is  engineering  and  programming.

 

Patented under U. S. Patent 5,762,942.Other patents pending. Plating Systems & Technologies offers various
licenses for this process.  HyperFlow is a trade mark of Plating Systems & Technologies. © Copyright 2000-2007 by
Plating Systems & Technologies, Inc..  All rights reserved.  Examples given in this publication are believed to be representative, but are not guaranteed.