OfiTE 170-182-1 User manual

HTHP Filter Press for Cement Testing
with 175-mL, Double-Capped Test Cell and N2Pressuring Manifold
#170-182: (115 V)
#170-182-1: (230 V)
Instruction Manual
Updated 6/20/2017
Ver. 3.0
OFI Testing Equipment, Inc.
11302 Steeplecrest Dr. · Houston, Texas · 77065 · U.S.A.
Tele: 832.320.7300 · Fax: [phone] · www.ote.com
©Copyright OFITE 2015

OFITE, 11302 Steeplecrest Dr., Houston, TX 77065 USA / Tel: [phone] / Fax: [phone] / www.ote.com 1
Intro..................................................................................................2
Specications .................................................................................3
Components ...................................................................................4
Safety...............................................................................................8
Quick Start ....................................................................................12
Operation.......................................................................................15
Data................................................................................................20
Cell Cap Assembly .......................................................................21
Maintenance..................................................................................22
Diagrams .......................................................................................24
Test Cell ....................................................................................25
Warranty and Return Policy ........................................................26
Table of
Contents

OFITE, 11302 Steeplecrest Dr., Houston, TX 77065 USA / Tel: [phone] / Fax: [phone] / www.ote.com 2
The OFI Testing Equipment (OFITE) High Temperature High Pressure
(HTHP) Filter Press is designed to evaluate the ltration characteristics of
drilling uids, cement slurries, fracturing uids, and completion uids under
elevated temperatures and pressures. Evaluating uids under HTHP condi-
tions similar to the downhole environment is of paramount importance. Fluid
properties must be monitored while under high temperatures and pressures
as ltration behavior and wall cake building characteristics of permeable
formations change with changing environments. These characteristics are
affected by the shape, type, and quantities of solids present in the uid and
their physical and electro-chemical interactions, all of which are affected by
changing temperatures and pressures.
OFITE manufactures and provides HTHP ltration units in two basic sizes,
175 mL and 500 mL capacities. Both are used extensively throughout the
world and in all environments, but in general the 175 mL units are designed
for eld portability, while the larger 500 mL units are designed for laboratory
usage at higher temperatures and pressures. All OFITE Filtration devices fully
conform to American Petroleum Institute (API) specications.
A complete HTHP Filter Press consists of a controlled pressure source, usu-
ally Nitrogen pressurization or Carbon Dioxide bulbs for the 175 mL units.
Top and bottom pressure manifolds are provided to simulate the differential
pressures found in a down-hole environment, and to prevent evaporation
of the base uid if exceeding the boiling point of that uid. The test cells are
provided in a variety of assemblies, depending upon the type of uid tested,
the lter media, and the temperatures and pressures desired. The test cells
are encased inside a heating jacket, which is adjustable.
A variety of lter media are available, the most common being standard API
lter paper, cement screens, and ceramic lters. The ceramic lters may be
obtained to match the pore throat or permeability of the formation. Natural for-
mation lters or cores may also be used of differing pore throat / permeability
sizes. Slotted disks of varying sizes are frequently used for lost circulation
materials studies.
Both the 175 mL and the 500 mL heating jackets are capable of reach-
ing 400°F (204°C), but lower uid volumes due to uid expansion at higher
temperatures, limit the 175 mL units to a useful working temperature of 300°F
(149°C). Anyone running tests above 350°F (177°C) must substitute a com-
plete set of o-rings after each and every test.
Intro

OFITE, 11302 Steeplecrest Dr., Houston, TX 77065 USA / Tel: [phone] / Fax: [phone] / www.ote.com 3
Size: 7.5" × 11" × 23.5" (19.1 × 27.9 × 59.7 cm)
Weight: 27 lbs. (12.3 kg)
Shipping Size: 17" × 23.5" × 12.5" (43.2 × 59.7 × 31.8 cm)
Shipping Weight: 38 lbs. (17.2 kg)
Maximum Temperature
(Heating Jacket): 400°F (204°C)
Maximum Temperature (Cell): 500°F (260°C)
Maximum Pressure (Cell): 5,000 PSI
Maximum Pressure (Receiver): 750 PSI (5.1 MPa)
Pressure Source: Nitrogen (at least 1,500 PSI / 10,343 kPa) -
Not Included
Test Cell Capacity: 175 mL
Receiver Volume: 15 mL
Heater: 400 Watt
Power Requirement: 115 VAC, 5 Amps, 50/60 Hz
230 VAC, 3 Amps, 50/60 Hz
Specications

OFITE, 11302 Steeplecrest Dr., Houston, TX 77065 USA / Tel: [phone] / Fax: [phone] / www.ote.com 4
Components #153-14 Graduated Cylinder, 50 mL × 1 mL
#154-10 Dual-Scale Thermometer with Dial, 5" Stem, 50° - 500°F (0° -
260°C)
#165-44-2 Anti Seize Compound, Silver, 7g Pouch
#170-00-1 Heating Jacket (115V) -OR-
#170-01-1 Heating Jacket (230V):
#130-10-52 Jam Nut; ⅜"-24; Stainless Steel; Qty: 2
#164-32 Male Connector for Power Cable (For 170-01-1 230V ONLY)
#170-05 Thermostat
#170-09 Insulation Board
#170-10 Thermostat Pilot Lot
#170-11 Heating Element; 115V; 200W; Qty: 2
#170-15 Base
#170-21 Stand Support Rod; Qty: 2
#170-25 Aluminum Well
#170-30 Stainless Steel Thermostat Cover
#170-44 ½" Rubber Foot; Qty: 4
#171-32 Midget Knob
#171-82 8' Power Cord with Male Plug 8; 16/3 SJ; Round (For 170-
00-1 115V ONLY)
#170-06-1 Back Pressure Receiver; 15-mL Stainless Steel Tube for N2
#144-11 ⅛" 90 Street Ell
#144-15 Plate Brass Bushing; ¼" NPT Male to ⅛" NPT Female
#170-07 O-ring
#170-28 Receiver Body
#170-32 ⅛" × ⅛" NPT Male Needle Valve
#171-23-1 Safety Pin with Lanyard
#170-19 Filter Paper; 2½" (6.35 cm); Specially Hardened for Filter Presses
#170-35 6" Adjustable Wrench
#170-182-S Test Cell, Stainless Steel (For Cement Testing)
#120-910-028 O-ring for Rupture Disk, Viton 75D, Qty: 1
#130-81-040 Retaining Ring, Qty: 2
#165-44-2 Anti Seize Compound, Silver, 7g Pouch, Qty: 4
#170-13-3 O-ring for Cell, Viton 75D, Qty: 4
#170-16 Valve Stem, Qty: 2
#170-17 O-ring for Valve Stem, Viton 75D, Qty: 4
#170-18 Cement Screen, Qty: 2
#170-180-020-S Cell Body, 175 mL, Qty: 1
#171-190-023 Locking Ring, Qty: 2
#171-190-027 Rupture Disk, Qty: 1
#171-190-029 Cap Wrench, Qty: 1
#171-190-032-S Cell Cap, Outlet, Cement, Qty: 1
#171-190-033-S Cell Cap, Inlet, Cement, Qty: 1
#171-190-057 O-ring for Valve Stem, Viton 90D, Qty: 4
#171-190-058 O-ring for Rupture Disk, Viton 90D, Qty: 1
#171-190-060 O-ring for Cell, Viton 90D, Qty: 4

OFITE, 11302 Steeplecrest Dr., Houston, TX 77065 USA / Tel: [phone] / Fax: [phone] / www.ote.com 5
#171-24 1350 / 750 PSI (9,308 / 5,171 kPa) Nitrogen Manifold
#170-08 Regulator; Qty: 2
#170-20 Manifold Block
#170-32 ⅛" × ⅛" NPT Male Needle Valve
#171-22 Retainer Pin
#171-24-1 Chrome Nut; R.H.; Reg Inlet CGA-580
#171-24-2 Nipple with Filter
#171-24-3 ¼" Flare × ⅛" FNPT Female
#171-24-4 ¼" NPT Pipe Plug; 316 Stainless Steel
#171-24-5 ¼" NPT Street Tee; 316 Stainless Steel; Qty: 2
#171-25-1 Relief Valve set at 750 PSI (5171 kPa)
#171-25-2 Relief Valve set at 1350 PSI (9308 kPa)
#171-26 5000# Hose;   " × 3'; Qty: 2
#171-28 Dual Manifold Body
#171-38 1,000 PSI Gauge; 2½"; ¼" NPT Bottom
#171-40 1,500 PSI Gauge; 2½"; ¼" NPT Bottom
#171-42 3,000 PSI Gauge; 2½"; ¼" NPT Bottom
#171-90-06 ¼" MNPT × ⅛" FNPT Reducing Bushing; 316 Stainless
Optional:
#170-13 O-ring for Test Cell, Buna, For tests below 300°F
#170-37 Nitrogen Cylinder; 21" × 7"; Right-hand Thread
Part Number Description Qty.
#143-00-1 Diaphragm for Airco Regulator 1
#143-07 Repair Kit for Regulator (#143-00) 1
#153-14 Graduated Cylinder, 50 mL × 1 mL 2
#154-10 Dial Thermometer, 5" Stem, 50° - 500°F and 0 - 250°C 1
#170-07 O-ring for Back Pressure Receiver, Nitrile 3
#170-13-3 O-ring for Cell, Viton 75D 50
#170-16 Valve Stem 4
#170-17 Valve Stem O-ring 100
#170-18 Cement Screen 10
#171-190-057 O-ring for Valve Stem, Viton 90D 100
#171-190-060 O-ring for Test Cell, Viton®50
#171-23-1 Safety Pin with Lanyard 1
#170-182-SP Spare Parts Kit:

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Optional Items for HTHP Filtration Testing:
The items listed below are not included in the HTHP Filter Press, but they are
items that will enable the technician to perform a more uniform and reproduc-
ible test while maintaining a high degree of safety. As optional items, the us-
age is not compulsory, but consideration should be given to these items when
running tests at elevated temperatures and pressures.
Interval Timer, 60 minute
(#155-20)
Cell Cap Removal Tool
(#170-33)
(Set Screw Cell Assemblies Only)
HTHP Pressure Relief Tool
(#170-91)
(To release trapped pressure)
Safety Shield (#171-06)
Cell Carrying Tool (#170-40)

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Thermocouple Assembly
(#171-45-1)
(Direct temperature measurement
Of the uid Inside the Cell)
Stand for HTHP Cell Assembly
(#171-190-028)

OFITE, 11302 Steeplecrest Dr., Houston, TX 77065 USA / Tel: [phone] / Fax: [phone] / www.ote.com 8
Safety Pressure and Temperature Considerations
Do not use or recongure this equipment in a manner not specied in this
manual.
Pressure
There are two reasons for operating at elevated pressures when performing a
ltration analysis.
1. To test uids at temperatures above the boiling point, the vessel must
be pressurized, which in turn elevates the vapor pressure (boiling
point) so that the uid remains liquid and does not turn to steam.
2. If testing for drilling applications, pressurization will more approximate
down-hole conditions, enabling the technician to match both bottom
hole temperatures and pressures.
HTHP Filter Presses are pressurized either with Carbon Dioxide or with
Nitrogen gas. The OFITE 175 mL HTHP Filter Press, 170-00 Series, is small
enough to be portable, so it is usually pressurized with small (65 mm length)
Carbon Dioxide (CO2) bulbs, which contain 10 cm3 of CO2 gas and weigh 8
grams. These bulbs are pressurized to approximately 1,000 PSI and they
contain plenty of carrier gas to run a complete 30 minute ltration test, if run-
ning the standard API 500 PSI differential test, which is usually 600 PSI on
the top manifold and 100 PSI on the bottom or back pressure.
For temperatures less than 200°F (93°C) a Back Pressure Receiver is not
required as the ltrate will not reach the boiling point. However when operat-
ing above the boiling point of water, a suitable Back Pressure Receiver is
required, otherwise the test uid will turn to steam and the test is invalidated.
The standard receiver tube supplied with the 175 mL HTHP Filter Press holds
15 mL of ltrate, so it is very important that the receiver outlet ball valve is
opened after approximately ten seconds of ltrate collection, as a uid with
poor ltration qualities can easily ll the 15 mL receiver tube almost instan-
taneously. If this happens the ltrate hopefully will all be ejected from the
safety bleeder valve, but if there is too much uid volume, the liquid may end
up inside the regulator rendering it useless which will require servicing by a
knowledgeable technician.
Temperature
Normally when one experiences a loss of pressure it is not due to a failure
of the metal alloy in the cell, but rather is a failure of the o-ring or elastomer,
which provides the seal. These o-ring may deform or melt under elevated
temperatures causing a pressurization failure of the cell, which is often sud-
den and catastrophic. For example, if the valve stem o-ring suddenly fails,
then steam at 400°F and under great pressure may shoot outward horizon-
tally in one or several directions. A safety shield should always be used when
operating any HTHP Filter Press and especially when one is going to extreme
temperatures and pressures. Above 350°F (176°C) All o-rings must be re-
placed after each and every test.

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Heating Jacket
Turn the thermostat knob on the front of the metal plate to change the tem-
perature of the heating jacket. The thermostat cover is marked from 1 to 10
and each whole number represents a separate temperature. Each lter press
will heat up a little differently so it is a good idea to mark with a pen directly
on the face-plate of the thermostat cover the temperature which corresponds
with each number. The actual temperature of the heating jacket is measured
with a stem thermometer and then the thermometer is placed into the cell
body.
The heating jacket will get very hot during the test so be careful not to touch
the outside of the jacket at any time during the heat-up period or the test. It is
especially easy to get burned when installing or removing the Back Pressure
Receiver as the technician is working in a very conned space. The power
cord is supplied for either 115 Volts or 230 Volts and due to the various types
of plug connectors around the world it may be necessary to change the plug
on the end of the power cord. The power cable is 8 feet in length and the
heating jacket should be placed no farther than 8 feet from the appropriate
electrical outlet. The heat up time will vary from one instrument to the next
and the pilot light will turn on when the set temperature has been reached.
The temperature of the uid inside the cell however will not be at the set tem-
perature, so always allow one hour of heating time for the uid, after the cell
has been fully inserted into the heating jacket.

OFITE, 11302 Steeplecrest Dr., Houston, TX 77065 USA / Tel: [phone] / Fax: [phone] / www.ote.com 10
The HTHP Filter Press is a very safe instrument to operate as long as the
instructions are strictly followed. It is imperative that the technician thoroughly
understands the assembly and disassembly procedures and also why the
order of steps is in place. Care should be taken to never use defective parts
and that OFITE’s temperature, pressure, and uid volume limits are strictly
adhered to at all times.
The heating jacket and cell will get very hot during the normal duration of the
test so the operator should take care to avoid burns. The operator should
be careful when attaching and removing pressure manifolds from the heat-
ing jacket, especially the Back Pressure Receiver assembly, which involves
operating in a small conned space.
Safety Retainer Pin
Always use a Safety Retainer Pin with an attached lanyard, and get in the
habit of securing the cotter pin to the pin. Improper placement of retainer pins
in the past have resulted in the pressure manifold separating from the lter
press which can cause damage to the equipment.
Normally the 175 mL HTHP Filter Press uses CO2 bulbs, for both portability
and pressurization. Even though they are small and appear innocuous, they
can contain pressures up to 1,000 PSI (6,900 kPa). CO2bulbs should never
be allowed to overheat. Exposure to re or carelessly leaving a box of bulbs
on an automobile dashboard in the sun may result in an explosion. Nitrous
Oxide (NO2) which is available in the same sized bulbs as the CO2, should
never be used as a pressure source for HTHP ltration. Under high tempera-
tures and pressures, Nitrous Oxide can detonate in the presence of grease,
oil or carbonaceous material.
Retainer Pin with Lanyard Safety Retainer Pin with Lanyard
(# 171-23-1)

OFITE, 11302 Steeplecrest Dr., Houston, TX 77065 USA / Tel: [phone] / Fax: [phone] / www.ote.com 11
Working Pressure
OFITE clearly stamps the working pressure of the cell assembly along with
the assembly serial number on each cell body and cell cap. These pressure
limits should never be exceeded on the pressure manifolds and uid vol-
umes inside the cell should strictly comply with instructions (see page 11).
However, in the past HTHP cells and caps from various manufacturers were
often not stamped, or in some cases, very old cell assemblies were stamped
“2500”. Cell assemblies with set screw secured caps should never be taken
to 2,500 PSI, under any temperature or condition.
O-ring Seals
Two sets of o-rings are included with the Filter Press. The rst set is made
from Viton 75D. These o-rings are black and should be used for tests up to
400°F only. The second set is made from Viton 90D. OFITE suggests that all
o-rings (cell caps, cell bodies, and valve stem) are changed each time after
running a test of 350° F (176° C) or above.
Fluid Expansion Space
Cells should never be lled completely with uid. Always leave some room for
the uid to expand under temperature. This keeps the cell caps from becom-
ing overstressed and possibly leading to a cell pressure failure or even a loss
of the cell cap completely.
Periodically check all gauges to ensure the proper pressures are in the cell,
as the pressure often increases or decreases depending upon the test proce-
dure and conditions.
API Recommended Void Space
Fluid / Temperature Void Space Fluid Volume
Water-based drilling uid. < 300°F 0.6" (1.5 cm) 138 mL
Water-based drilling uid. > 300°F 1.5" (4.0 cm) 86 mL
Oil-based drilling uid. < 350°F (176°C) 1" (2.5 cm) 115 mL
Oil-based drilling uid. > 350°F (176°C) Not Recommended-
Use 500 mL Cell
Void Space in a 1,500 PSI rated cell body

OFITE, 11302 Steeplecrest Dr., Houston, TX 77065 USA / Tel: [phone] / Fax: [phone] / www.ote.com 12
Quick Start 1. Place the thermometer in the heating jacket.
2. Preheat the heating jacket to 10°F (6°C) above the test temperature. The
pilot light will turn on at the target temperature.
3. Inspect all o-rings. Replace any that show signs of damage or wear.
4. Apply grease to all o-rings.
5. Assemble both cell caps. Place an o-ring in the groove around the cap.
6. Make sure all threads are clean and free of debris.
7. Apply anti seize compound (#165-44-2) to the threads of the cell locking
rings and valve stems.
8. Place an o-ring in the groove in the inlet side of the cell.
9. Place cement screen on top of the o-ring.
10. Screw the inlet cell cap into the cell and tighten it completely.
11. Screw a valve stem into the inlet cell cap and tighten it completely.
12. Pour the test uid into the cell. Leave adequate space for uid expansion.
13. Place an o-ring in the groove inside the cell.
14. Place a cement screen on top of the o-ring.
15. Screw the outlet cell cap into the cell. Tighten it completely.
16. Screw a valve stem into the outlet cell cap and tighten it completely.
17. Invert the cell and place it in the heating jacket. Rotate the cell until it
seats.
18. Transfer the thermometer to the cell body.
19. Connect the manifold block from the dual Nitrogen manifold to the top
valve stem and secure it with the safety pin.
20. Screw the hose from the dual Nitrogen manifold into the back pressure
receiver.
21. Connect the back pressure receiver to the bottom valve stem and secure
it with the safety pin.
22. Connect a Nitrogen cylinder to the dual Nitrogen manifold.

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23. Adjust both regulators to the target back pressure for the test.
24. Open the top valve stem ½ turn.
25. After heat time, increase the top pressure to 500 PSI above the back
pressure.
26. Open the bottom valve stem to initiate ltration.
27. Collect ltrate and record the volume at 1, 7.5, and 30 minutes.
28. After 30 minutes, close both valve stems.
29. Turn both regulator T-screws counterclockwise.
30. Open the outlet valve on the back pressure receiver to collect any remain-
ing ltrate.
31. Open the valve on the manifold block to release any remaining pressure.
32. Remove the manifold block and back pressure receiver.
33. Allow the cell to cool in the heating jacket.
34. Once the cell has cooled to room temperature, remove it from the heating
jacket.
35. Slowly open the valve stem on the inlet side to release the pressure.
36. Unscrew the outlet cell cap.
37. Wash the lter cake and record the thickness to the nearest   ".
38. Clean and dry all components.

OFITE, 11302 Steeplecrest Dr., Houston, TX 77065 USA / Tel: [phone] / Fax: [phone] / www.ote.com 14
Manifold Block
(#170-20)
Heating Jacket
(#171-00 or 171-01)
Thermostat
(#171-71)
Thermometer
(#154-10)
Back Pressure
Receiver
(#171-10)
Nitrogen Manifold
(#171-24)
Valve Stem
(#170-16)
Regulators
Nitrogen
Connection
Male End of
Hose (For Back
Pressure (⅛")
Manifold Block
(For Inlet Pressure)
(#170-20)
Nitrogen Manifold
(#171-24)

OFITE, 11302 Steeplecrest Dr., Houston, TX 77065 USA / Tel: [phone] / Fax: [phone] / www.ote.com 15
Operation 1. Plug the heating jacket into an appropriate power source. Place a ther-
mometer (#154-20) into the heating well and preheat to 10°F (6°C) above
the test temperature. A pilot light will come on when the heating jacket
reaches the temperature set by the control knob.
2. If the cell caps are not already assembled, see page 21 for assembly
instructions.
3. Inspect the cell cap and cell body. Discard any components that show
signs of corrosion, damage, or wear.
4. Inspect all o-rings. Replace any that show signs of damage or wear.
Looks for nicks, cuts, or brittle o-rings. Replace all o-rings after any test
above 350°F (176.7°C). Place a thin lm of silicone grease on all o-rings.
5. Place an o-ring (#170-13-3) on the shoulder inside the cell body on the
end marked “In”. Place another o-ring in the groove around the cell cap.
6. Place a cement screen on top of the o-ring.
7. Make sure all threads are clean and free of debris.
8. Apply anti seize compound (#165-44-2) to the threads of the cell locking
rings and valve stems.
Cement Screen
(#170-18)
O-ring
(#171-190-060)
Valve Stem
(#170-16)
O-ringO-ring

OFITE, 11302 Steeplecrest Dr., Houston, TX 77065 USA / Tel: [phone] / Fax: [phone] / www.ote.com 16
9. Screw the inlet cell cap into the cell body.
The cell cap should turn smoothly in the threads and not require any tools
for complete tightening. If you encounter resistance, carefully unscrew
the cap and start over. Make sure the threads are properly seated before
tightening completely.
10. Place an o-ring in each of the two o-ring grooves on both valve stems.
11. Screw one valve stem into the inlet cell cap. Tighten the valve stem com-
pletely.
To increase the life of the valve stem and cap, apply a thin layer of high-
temperature thread lubricant (#165-44-1) to the tip of the valve stem.
12. Prepare the test uid.
13. Invert the cell body and carefully pour the sample into the cell. Leave 2"
(5.1 cm) void space for thermal expansion.
Be careful not to spill uid on the o-ring shoulder inside the cell.
14. Place an o-ring in the cell and another on the cell cap.
15. Place a cement screen on top of the cell o-ring.
16. Screw the outlet cap into the cell body.
17. Screw the other valve stem into the outlet cell cap and tighten it com-
pletely.
18. Invert the cell and place it in the heating jacket with the outlet (lter) side
pointed down. Rotate the cell in the heating jacket so that the pin in the
bottom of the heating well seats into the hole in the bottom of the test
cell. This will anchor the cell in the well and prevent it from rotating as the
valve stems are opened and closed.
19. Move the thermometer from the heating jacket to the hole in the test cell.
Allow the cell to heat for one hour. Start a 60 minute timer now.

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20. Connect the manifold block from the dual Nitrogen manifold to the top
valve stem and lock it in place with the safety pin. Place the back pressure
receiver on the bottom valve stem and lock it in place with the safety pin.
The safety pin includes an attached lanyard. The lanyard secures the pin
and prevents it from accidentally disengaging from the valve stem and
pressure assembly. Always secure the pin with the lanyard.
21. Connect the male end of the pressure hose to the back pressure receiver
(if it is not already connected). Make sure the needle valve on the back
pressure receiver is closed.
22. Unscrew the regulator T-screws (counterclockwise) on the pressure mani-
fold to make sure both regulators are completely closed.
23. Connect a Nitrogen cylinder (at least 1,500 PSI) to the center inlet on
the pressure manifold. Open the pressure release valve on the Nitrogen
bottle and note the bottle pressure as registered on the middle manifold
gauge.
24. Keeping the valve stems closed, adjust the top and bottom regulators to
the recommended back pressure for your test (see chart below). Make
sure the ball valves and bleeder valves are all closed.
The upper and lower limits of the test pressure differential are determined
by the test temperature. As this temperature exceeds 212°F (100°C), the
back pressure must be increased in order to prevent vaporization of the
ltrate. The 500 PSI differential pressure must be maintained, so the top
pressure will have to be increased accordingly. The table below shows
the pressures recommended for various test temperatures.
Recommended Minimum Back Pressure
Test Temperature Vapor Pressure Minimum Back Pressure
°F °C PSI kPa PSI kPa
212 100 14.7 101 100 690
250 121 30 207 100 690
300 149 67 462 100 690
350 177 135 932 160 1,104
400 204 247 1,704 275 1,898
Manifold
Block
(#170-20)
Safety Pin
(#171-23-1)
Safety Pin
(#171-23-1)
Back Pressure
Receiver
(#170-11)

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25. Open (loosen) the top valve stem ½ turn to pressurize the sample. Main-
tain this pressure on the uid until the temperature has stabilized.
26. After the one hour heat up time, increase the pressure on the top pres-
sure unit to 500 PSI (3,448 kPa) more than the back pressure.
27. Open (loosen) the bottom valve stem ½ turn to initiate ltration as soon as
possible.
Closely monitor the pressure gauges. If at any time during the test the
pressure inside the cell rises above the setpoint, carefully open the
needle valve on the top pressure assembly just enough to bleed off the
excess pressure. Then close the valve. If the cell pressure decreases due
to collection of ltrate, increase the pressure with the inlet regulator.
28. To collect ltrate, carefully open the ball valve on the bottom of the back
pressure receiver while holding a graduated cylinder up to the valve port.
Close the valve immediately after the pressure begins to decrease and
the ltrate is collected.
Collect ltrate at 10 seconds, 1 minute, 7.5 minutes, and 30 minutes.
The initial 10 second collection is precautionary in nature, as a uid with
little ltration properties may ll up the 15 mL receiver tube almost imme-
diately, potentially damaging the regulator. Do not record the 10 second
collection as a separate notation, but do record the volume collected at
the other time intervals.
While collecting ltrate, maintain the test temperature within ± 5°F (±3°C).
If the back pressure rises during the test, cautiously reduce the pressure
by opening the valve on the receiver and drawing off some of the ltrate
into the graduated cylinder.
29. At the end of the test, close (tighten) the top and bottom valve stems to
seal off the cell.
30. Turn both regulator T-screws counterclockwise to close off the ow of
pressurized gas.
31. Open the outlet valve on the back pressure receiver to collect all of the
remaining ltrate.
32. Open the bleeder valve on the manifold block to release any remaining
pressure in the line.
33. Remove the manifold block and the back pressure receiver. Drain any
residual ltrate from the receiver into the graduated cylinder.
The heating jacket will still be very hot. Be careful not to touch it while
removing the back pressure receiver.

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34. Allow the cell to cool to room temperature.
35. Remove the cell from the heating jacket after once again checking that
the valve stems are tightly closed.
An optional Cell Carrying Tool (#170-40) makes this a simple and safe
operation.
The test cell will still be under approximately 600 PSI (4.140 kPa) of pres-
sure. To avoid possible injury, keep the cell upright and cool it to room
temperature before disassembling. The cell must be cool for at least one
hour at room temperature before removing the cell cap.
36. Using extreme care to save the lter cake, place the cooled cell upright
with the outlet side down. Slowly open (loosen) the inlet valve stem to
bleed off pressure from the cell body.
Pressure cannot be relieved from the cell by opening the outlet valve
stem as the lter cake will seal off the cell. It is a good idea to open the
valve stem with the cell inside a sink or with a rag over the valve stem in
order to catch any liquid that might be ejected.
37. Once the pressure is released, tighten the valve stem again to keep the
uid inside. Then turn the cell over.
38. Loosen the valve stem and unscrew and remove the outlet cell cap. Use
the supplied cell cap wrench to loosen the threads.
If the cell cap is difcult to unscrew, the pressure port may be clogged.
Use the HTHP Pressure Relief Tool (#170-91) to clear the obstruction.
39. Carefully remove the cement screen and deposited cake. Be careful not
to damage the lter cake. Carefully wash any residual uid from the sur-
face of the lter cake.
40. Pour out the test uid.
41. Clean and dry the apparatus thoroughly after each use. Inspect all of the
o-rings and replace any that show signs of wear or damage.