Altek Model 638 Precision High Pressure Pump Data Sheet User Manual

							GENERAL DESCRIPTION
PRECISION HIGH-PRESSURE PUMP
DATA SHEET 638: 
See Data Sheets 628 for Low Pressure Pump & 620 for Pressure Indicators
ALTEK
MODEL 638
with psig, inches of water or kg/cm2 ranges.
Dual output ports allow simultaneous pressure
application to two devices.  For example, connect
one port to the Model 620—providing digital veri-
fication of the generated pressure—and the sec-
ond port to the device being checked or calibrated.
Pressure connections are made through two 
1/4
NPT internally threaded fittings. Compatible me-
dia are any non-conductive, non-corrosive, instru-
ment-grade clean air or inert gas.
Generate higher pressures with less effort using the
Model 638. Its long stroke and large piston require
30% less effort than other hand pumps to get to 100
PSI. 50% less effort is required to get to 300 PSI.
The pump’s moderate size and sqeeze-action
mechanism permit easy, one-handed operation at
any angle. Although the unit is lightweight (less
than two pounds), it is ruggedly constructed to
withstand typical field use. The pump body is
nylon, which resists chemicals and protects against
impact damage and corrosion. The output ports
and piston rod are stainless steel. Model 638’s
simple design and quality construction ensure a
long service life with virtually no maintenance.
When cleaning is required the Model 638 can be
stripped down, lubricated, have new filters & O-rings
installed and reasssembled in 10 to 15 minutes. Generate pressure where you need it with Altek’s
Model 638 Precision High-Pressure Pump. Cali-
brate higher pressure transmitters & low pressure
switches without bottle gas or hydraulic fluid!
Get to the pressure you need faster and easier
than with older style pumps. A large diameter
cylinder and compound mechanism combine to
generate 100 psi two to four times faster. And  with
just a few additional squeezes the Model 638 gives you
150, 300 or even 600 psi.
Effortlessly adjust pressure to 0.001 psi  with a fine
adjustment vernier. Top adjusting pumps have
vernier adjustment which  become harder to turn
as the output pressure increaces. The Model 638
has a balanced pressure adjustment which is
easy to turn at any output pressure.
Gently lower the pressure by opening the pat-
ented micro bleed valve ˘ turn, which releases the
pressure very gradually. Open the micro bleed
valve fully to quickly vent the pressure. The bleed
valve has no seat to deform, eliminating the prob-
lems associated with needle valves on other
pumps.
Use the Model 638 independently or in conjunc-
tion with ALTEK’s Model 620 or other pressure
indicator, forming a convenient source/indicator • PORTABLE PRESSURE SOURCES
Generate up to 600 psig, 41 kg/cm
2 or 4135 kPa
• CHOOSE ONE OF THREE RANGES
Model 638-600 – 600 psig, 41 kg/cm
2 or 4135 kPa
Model 638-300 – 300 psig, 21 kg/cm2 or 2070 kPa
• COARSE AND FINE  ADJUSTMENTS
Provide resolution to 0.001 psig
• DUAL OUTPUT PORTS
Simultaneous connection to two devices
• CONVENIENT, ONE-HANDED OPERATION
Functions at any angle
PRODUCING PRESSURE
ALTEK INDUSTRIES CORP
35 Vantage Point Drive Rochester, New York  14624  U.S.A.
(716) 349-3500 • Fax: (716) 349-3510
E-Mail: [email protected] • http://www.altekcalibrators.com
A TRANSMATION COMPANY 
						

							SPECIFICATIONS
CONNECTIONS
To install a pressure fitting in the Model 638:
1) Turn the BLEED VALVE counterclockwise to bleed any pressure
2) Remove the stainless steel port fitting from the pump body
3) Place the stainless steel port fitting in a vise and install a pressure fitting
into the port fitting.
4) Hold the pump with the handles up and insert the stainless steel port
fitting into the pump. Make sure that the O-ring and filter do not fall out.
5) Snug the fitting assembly using the wrench but do not overtighten. The
O-ring compresses slightly to provide the seal. Overtightening may
damage the O-ring or pump body.
LEAK PREVENTION AND DETECTION
ALTEK INDUSTRIES CORP
Rochester, NY 14624 USA
IMPORTANT: Read all operating instructions and general operating information before beginning any test procedures.
1) Connect one of the Model 638’s  ports to the instrument
to be calibrated or checked.  Use small-diameter
tubing as short in length as possible (this will maximize
the pressure adjustment range). An auxiliary port is
provided for simultaneous output to a second device,
e.g., application of pressure to an instrument or
system under test and to a Model 620 to measure the
actual pressure output.  If the auxiliary port is not
used, it should be securely plugged.
2) Set the FINE ADJUST knob to the full
counterclockwise position.
3) Turn the BLEED VALVE knob fully counterclockwise
to relieve all system pressure and zero any measuring
devices.
4) Turn the BLEED VALVE knob fully clockwise to
close.
5) Repeatedly squeeze the handles to generate just
under the desired pressure.
6) Use the FINE ADJUST knob to bring up the pressure
to the precise level. The FINE ADJUST knob can
adjust the pressure up from and down to the pressure
generated by squeezing the levers.7) Use the BLEED VALVE to lower the pressure from he
pressure generated by squeezing the levers. Opening
the BLEED VLAVE 
1/4 turn will lower the pressure very
gradually. Opening it 1/2 turn will release the pressure
faster and opening it 3/4 turn will quickly and safely
release all the pressure in the system.
WARNING
It is imperative that all system pressure is relieved prior to
making any connections or disconnections. Failure to
relieve system pressure could result in serious personal
injury or equipment damage. Even nominal pressure
values can generate extreme force if fitting or tubing
failure occurs due to improper installation or usage.
Since the Model 638 is capable of generating pressures
exceeding 100 psig, it is important that all pressure
connections and test procedures be done by qualified
service personnel, according to standard engineering
practices, to prevent possible personal injury or equipment
damage.
OUTPUT RANGE:
   638-600: 600 psig, 41 kg/cm2 or 4135 kPa
   638-300: 300 psig, 21 kg/cm2 or 2070 kPa
RESOLUTION:  0.001 psig
PRESSURE CONNECTIONS
  Primary Port:
 1/4-18 NPT
  Auxiliary Port: 1/4-18 NPTWEIGHT: 0.9 kg (2 lbs.)
MEDIA COMPATIBILITY:  Non-conductive, non-
corrosive, instrument-grade clean air or inert gas
CONSTRUCTION:  Nylon pump body; stainless steel
output ports and piston rod
In order to obtain maximum pressure indication stability,
leaks must be avoided. It is strongly recommended that
either Teflon® tape or commercial pipe sealant be used at
all tapered fittings and connections. If Teflon
® tape is used,
care must be taken that the proper amount is applied.
Excessive tape may fray and cause plugging of relief
valves, orifices, nozzles, etc.  Overuse of pipe sealant may
cause similar problems.
External equipment should also be checked carefully for
leaks. Process connections, flange bolts, and vents must
be tightly closed. Defective gaskets, leaking valves, and
damaged diaphragms are all potential sources of leaks.
For detection of very small system leaks, the traditional
soap bubble method may not be sufficient. Halogen leak
detection devices may be required when using highly
sensitive pressure calibration equipment.
TEMPERATURE CONSIDERATIONS
Since the pressure change of a contained volume of gas is
directly proportional to absolute temperature, temperature
control is critical when using the Model 638 with any high-
resolution measuring device. Tubing should be kept away
from heat sources (i.e., lamps, operating electronic equip-
ment, excessive hand contact, etc.) as well as from heat-
dissipating structures (i.e., open windows, air conditioning
vents, etc.) to minimize temperature variations that might
induce errors.
Air is compressed when the Model 638’s actuating levers are
squeezed. This compression causes some heating of the air as
it is forced into the system.  Consequently, a noticeable de-
crease in pressure—caused by the cooling of the newly com-
pressed air—may occur immediately after cessation of
pumping.
0
50
10 0
OPERATING INSTRUCTIONS
GENERAL OPERATING INFORMATION 
						

							


	






















MAINTENANCE
ALTEK INDUSTRIES CORP
Rochester, NY 14624 USA
SERVICE NOTES
Please read before attempting any repair of this product
Field service procedures for the Model 638 include replacing the O-rings,
filters, and replacing damaged assemblies. It is strongly recommended
that units requiring service beyond the scope of the procedures described
below be returned to the nearest service location (refer to Section 5 for
return and warranty information). Unauthorized repair or replacement of
components may impair accuracy and/or void the warranty. No equip-
ment will be accepted for service unless all process materials have been
completely removed from all components by the customer. Contaminated
pumps will be returned to the customer for proper cleaning.
NOTE: To prevent clogged internal passageways, exercise extreme care
to avoid introducing contaminants into the pump body orifice. It is highly
recommended that the following procedure be performed in a clean
environment.
WARNING! It is imperative that all system
pressure be relieved prior to making any con-
nections or disconnections. Failure to relieve
system pressure could result in serious per-
sonal injury or equipment damage.
Refer to this diagram for all procedures on this page
Replacing the Piston Assembly
Tools Required: 3/32” Allen wrench; 3/4” wrench; Pliers
1) Turn the Bleed Valve fully counterclockwise to bleed all air.
2) Remove the two cover set screws and remove the cover.
3) Using the pliers, remove both handle assembly dowel pins.
4) Slowly actuate the handles until the handle assembly “pops” out of the
pump body.
5) Grasp the steel shaft to prevent turning.  Use care to avoid damaging
the shaft surface.
6) Using the wrench, unscrew the piston.  Notice that wrench flats are
supplied on the piston.
7) Install the replacement piston and snug with the wrench.  Do not
overtighten.
8) Install the handle assembly into the pump body.
9) Visually align the handle assembly/pump body dowel holes and install
both dowel pins.
10) Install the front cover and set screws.
11) Check for proper pump operation.
Replacing the Volume Adjust Assembly
Tools Required: 3/32” Allen wrench; Pliers
1) Turn the Bleed Valve fully counterclockwise to bleed all air.
2) Remove the two cover set screws and remove the cover.
3) Using the pliers, remove both volume adjust assembly dowel pins.
4) Withdraw the volume adjust assembly from the pump body.
5) Install the new volume adjust assembly.
6) Visually align the volume adjust assembly/pump body dowel holes and
install both dowel pins.
7) Install the front cover and set screws.
8) Check for proper pump operation.
Replacing the Bleed Valve Assembly
Tools Required: 1/16” Allen wrench; 5/8” wrench
1) Turn the Bleed Valve fully counterclockwise to bleed all air.
2) Using the Allen wrench, loosen the knob set screw.
3) Remove the knob.
4) Using the wrench, remove the bleed valve assembly from the pump
body.
5) If necessary, install new filters in the bleed valve assembly (two filters
are stacked on top of each other).
6) Orient the pump with the aperture down to prevent the filter or O-ring
from being dislodged, then install the bleed valve assembly into the
pump body.  Snug the fitting using the wrench; do not overtighten.
7) Check for proper pump operation.
Replacing a Pressure Fitting
Tools Required: 3/4” wrench
1) Turn the Bleed Valve fully counterclockwise to bleed all air.
2) Using the wrench, remove the output port fitting from the pump body.
NOTE: 
It is highly recommended that the output port fitting be removed
from the Model 638 prior to pressure fitting removal or installation.  The
torque required to remove or install a pressure fitting in the output port
fitting may exceed the pump body thread strength.
3) Secure the output port fitting in a vise or equivalent, remove the existing
pressure fitting, then install a suitable replacement pressure fitting.
4) Invert the pump body (e.g. the handles up, the fitting aperture down) to
prevent the O-ring or filter from being dislodged from the output port
fitting, then install the output port/pressure port fitting assembly into the
pump body.  Snug the fitting assembly using the wrench; do not
overtighten.
5) Check for proper pump operation. 
						

							REPLACING FILTERS AND O-RINGS
MAINTENANCE
Servicing the Stage 1 Check Valve
Tools Required:3/32” Allen wrench, Large blade screwdriver
1) Turn the Bleed Valve fully counterclockwise to bleed all air.
2) Remove the two cover set screws and remove the cover.
3) Using the screwdriver, remove the valve keeper.
4) Invert the pump and remove the brass valve stem.
5) Remove the face seal O-ring, Tygon tube, and keeper O-ring from the
valve stem.
6) Using a suitable lubricant, lube the replacement face seal O-ring and
keeper O-ring.
NOTE: 
When lubricating O-rings, use a silicone-based
O-ring lubricant such as Parker Super Lube.  Fully wet all O-ring
surfaces, then wipe off all excess lubricant.
7) Install the replacement face seal O-ring, Tygon tube, and keeper O-ring
on the valve stem as illustrated in Figure 4-2.  Center the Tygon tube
on the raised ridge of the valve stem.
8) Install the valve stem in the proper orientation in the pump body.  Verify
that the valve stem is seated properly.
9) Using the screwdriver, snug the valve keeper.  Do not overtighten.
10) Install the front cover and set screws.
11) Check for proper pump operation.
Refer to this diagram for Stage 1 Check Valve
Periodic inspection and replacement of selected O-rings and
filters is recommended to ensure proper and safe pump operation.
A service kit (P/N 36-009) is available that contains all serviceable
filters and O-rings.
Replacing a Filter
1) Remove the applicable assembly (i.e. Piston Assembly, Bleed Valve,
or output port fitting) as instructed in the corresponding section.
2) Remove the old filter(s).
3) Verify that the filter seat is free from debris or contamination, then install
the replacement filter(s).
4) Install the assembly as described in the corresponding section.
Replacing an O-Ring
1) Remove the applicable assembly (i.e. Piston Assembly, Stage 1 Check
Valve, Volume Adjust, Bleed Valve, or output port fitting) as instructed
in the corresponding section.
2) Remove the old O-ring(s).
3) Using a suitable lubricant, lube the replacement O-ring(s).
NOTE: 
When lubricating O-rings, use a silicone-based
O-ring lubricant such as Parker Super Lube.  Fully wet all O-ring
surfaces, then wipe off all excess lubricant.
4) Install the replacement O-ring(s).
5) Install the assembly as described in the corresponding section.
ONE YEAR WARRANTY
Our equipment is guaranteed against defective material and workman-
ship  for a period of one year from date of shipment. Claims under
guarantee can be made by returning the equipment prepaid to our factory.
The equipment will be replaced, repaired or adjusted at our option. The
liability of Altek is restricted to that given under our guarantee No
responsibility is accepted for damage, loss or other expense incurred
through sale or use of our equipment. Under no condition shall Altek be
liable for any special, incidental or consequential damage.
No pump will be accepted for service unless all process materials have
been completely removed from all components by the customer. Con-
taminated pumps will be returned to the customer for proper cleaning.
ORDERING INFORMATION
DESCRIPTION MODEL   No.
600 psi Precision High Pressure Pump 638-600
300 psi Precision High Pressure Pump 638-300
ACCESSORIES
Carrying Case 09-3785
Quick-Connect Kit, 3 (1 Meter) 36-300
Quick-Connect Kit, 6 (2 Meter) 36-301
External Port Adapter 
1/4-18 NPTF 36-231
External Port Adapter 1/8-27 NPTF 36-232
Output Port Plug 36-233
RECOMMENDED SPARE PARTS
O-Ring/Filter Kit 36-009
Handle/Piston Assembly 36-050
Bleed Valve Assembly 36-040
Volume Adjust Assembly 36-030OTHER PRODUCTS
Altek designs and manufacturers fast, accurate instruments for measure-
ment, generation and simulation of virtually every process control signal.
Consult our factory directly or contact your local stocking representative to
order precise, low cost Milliamp Calibrators, Voltage Sources, Direct
Thermocouple Sources, RTD Simulators, Frequency Sources and Pres-
sure Pumps & Indicators. Altek also produces calibrators for custom
ranges and unique applications. Additional models and ranges are fre-
quently added to the Altek instrument family to meet all of your critical
calibration requirements. Altek products are made in the USA.
AVAILABLE FROM:
     © September 1998 Altek Industries Corp Rochester, NY 14624 USA
         100836-902 REV:A