Taylor-Wharton LP3 User Manual

Laser Pak III

Part Number LP3000

Do not attempt to use or maintain these units until you read and understand these instructions. Refer to the Taylor­Wharton’s Safety First

aintain this equipment. If you do not understand these instructions, contact your supplier for additional information. m

booklet (TW-202) for handling cryogenic material. Do not permit untrained persons to use or

Table of Contents

WARNING 3

Safety Precautions for Liquid Oxygen 3
Safety Precautions for Liquid Nitrogen 4

INTRODUCTION 5

System Description 5

PIPING CIRCUITS 6

Fill and Vent Circuits 7
Express Fill Circuit 8
Pressure Building Circuit 9
Gas Withdrawal Circuit 10
Economizer Circuit 11
Safety Devices 12
Instrumentation Circuits 13

OPERATION 14

Receiving Inspection 14
Handling 14
Determining Proper Fill Weight 14
Filling by Pressure Transfer 14
Filling by Pump Transfer 15
Withdrawing Gas 15
Withdrawing Liquid 16
Changing Gas Service 16

MAINTENANCE 17

Leak Test 17
Globe Valves 17
Regulators 18
Instruments 19
Checking Vacuum 19
Trouble-Remedy Guide 21
Replacement Parts 22

APPENDIXES 23

Laser Pak III General Arrangement

WARNING

The following safety precautions are for your protection. Before installing, operating, or maintaining this unit
read and follow all safety precautions in this section and in reference publications. Failure to observe all
safety precautions can result in property damage, personal injury, or possibly death. It is the responsibility of
the purchaser of this equipment to adequately warn the user of the precautions and safe practices for the use of
this equipment and the cryogenic fluid stored in it.

CAUTION: When installing field fabricated piping, make certain a suitable safety valve is installed in
each section of piping between shut-off valves.

For more detailed information concerning safety precautions and safe practices to be observed when handling
cryogenic liquids consult CGA pamphlet P-12 "Handling Cryogenic Liquids" available from the Compressed
Gas Association, 1235 Jefferson Davis Highway, Arlington, VA 22202.

Safety Precautions for Liquid Oxygen

Oxygen is a colorless, odorless, and tasteless gas that can be condensed into a liquid at the low temperature of
297 degrees below zero Fahrenheit (-183°C) under normal atmospheric pressure. Approximately one-fifth of
normal air is oxygen. As a liquid, oxygen is pale blue in color. Oxygen is non-flammable, however it
vigorously accelerates the burning of combustible materials.

Keep Combustibles Away from Oxygen and Eliminate Ignition Sources
Many substances that do not normally burn in air require only a slight spark or moderate heat to set them
aflame in the presence of concentrated oxygen. Other substances, which are only moderately combustible in
air, can burn violently when a high percentage of oxygen is present.

Do not permit smoking or open flame in any area where liquid oxygen is stored, handled, or used. Keep all
organic materials and other flammable substances away from possible contact with liquid oxygen. Some of
the materials that can react violently with oxygen are oil, grease, kerosene, cloth, wood, paint, tat, and dirt that
contains oil or grease. Under certain conditions flammable materials that have become permeated with liquid
oxygen are impact sensitive and can detonate if subjected to shock.

Keep Area and Exterior Surfaces Clean to Prevent Ignition
As normal industrial soot and dirt can constitute a combustion hazard, all equipment surfaces must be kept
very clean. Do not place oxygen equipment on asphalt surfaces, or allow grease or oil deposits to remain on
benches or concrete surfaces in the vicinity of the oxygen equipment. Use cleaning agents, which will not
leave organic deposits, on the cleaned surfaces. Equipment to be used in contact with liquid oxygen should be
handled only with clean gloves or hands washed clean of oil.

Maintain Adequate Ventilation
Enclosed areas containing oxygen equipment should be ventilated to prevent accumulations of oxygen and
thereby minimize combustion hazards.

Extreme Cold - Cover Eyes and Exposed Skin
Accidental contact of liquid oxygen or cold issuing gas with the skin or eyes may cause a freezing injury
similar to frostbite. Handle the liquid so that it won't splash or spill. Protect your eyes and cover the skin
where the possibility of contact with the liquid, cold pipes and equipment, or the cold gas exists. Safety
goggles or a face shield should be worn if liquid ejection or splashing may occur or cold gas may issue
forcefully from equipment. Clean, insulated gloves that can be easily removed and long sleeves are
recommended for arm protection. Cuffless trousers should be worn outside boots or over the shoes to shed

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spilled liquid. If clothing should be splashed with liquid oxygen or otherwise saturated with the gas, air out
the clothing immediately, removing it if possible. Such clothing will be highly flammable and easily ignited
while the concentrated oxygen remains, and should not be considered safe for at least 30 minutes.

Replacement Parts Must be Suitable for Oxygen Service
Many materials, especially some non-metallic gaskets and seals, constitute a combustion hazard when in
oxygen service, although they may be acceptable for use with other cryogenic liquids. Make no substitutions
for recommended spare parts. Also, be sure all replacement parts are thoroughly "Cleaned For Oxygen
Service" in accordance with Compressed Gas Association (CGA) Pamphlet G-4.1 "Cleaning for Oxygen
Service" or equivalent industrial cleaning specifications.

Observe Safety Codes When Locating Oxygen Equipment
Before locating oxygen equipment, become thoroughly familiar with National Fire Protection Association
(NFPA) Standard No. 50, "Bulk Oxygen Systems", and with all federal, state and local safety codes. The
NFPA Standard covers the general principles recommended for the installation of bulk oxygen systems on
industrial and institutional consumer premises.

Safety Precautions for Liquid Nitrogen

Nitrogen is an inert, colorless, odorless, and tasteless gas making up four-fifths of the air you breathe. Liquid
nitrogen is obtained by cooling air until it becomes a liquid and then removing the oxygen. Air is roughly
one-fifth oxygen. Liquid nitrogen is at a temperature of -320°F (-196°C) under normal atmospheric pressure.

Extreme Cold - Cover Eyes and Exposed Skin
Accidental contact of liquid nitrogen or cold issuing gas with the skin or eyes may cause a freezing injury
similar to frostbite. Handle the liquid so that it won't splash or spill. Protect your eyes and cover the skin
where the possibility of contact with the liquid, cold pipes and equipment, or the cold gas exists. Safety
goggles or a face shield should be worn if liquid ejection or splashing can occur or cold gas can issue
forcefully from equipment. Insulated gloves that can be easily removed and long sleeves are recommended
for arm protection. Trousers without cuffs should be worn outside boots or over the shoes to shed spilled
liquid.

Keep Equipment Area Well Ventilated
Although nitrogen is non-toxic and non-flammable, it can cause asphyxiation in a confined area without
adequate ventilation. Any atmosphere not containing enough oxygen for breathing can cause dizziness,
unconsciousness, or even death. Nitrogen, a colorless, odorless, and tasteless gas, cannot be detected by the
human senses and will be inhaled normally as if it were air. Without adequate ventilation, the expanding
nitrogen will displace the normal air resulting in a non-life-supporting atmosphere.

Dispose of Waste Liquid Nitrogen Safely
Dispose of waste liquid nitrogen out-of-doors where its cold temperature cannot damage floors or driveways
and where it will evaporate rapidly. An outdoor pit filled with clean sand or gravel will evaporate liquid
nitrogen safely and quickly.

NOTE: Argon is an inert gas whose physical properties are very similar to those of nitrogen. For
handling of liquid argon, follow the safe practices described for the handling and use of liquid nitrogen.

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INTRODUCTION

This manual provides information for the operation and maintenance of Taylor-Wharton's Laser Pak III
transportable cryogenic gas supply system. The Laser Pak III is designed for applications requiring nitrogen,
argon, or oxygen gas at pressures and flow-rates higher than possible with traditional pallet base cryogenic
vessels. The Laser Pak III is capable of delivering gas at a continuous rate of 2,000 standard cubic feet per
hour while maintaining a supply pressure exceeding 350 psig. Gas delivery rates of 3,000 standard cubic feet
per hour are possible during intermittent use.

Product specifications, flow diagram, views, and important dimensions are shown on the general arrangement
drawing provided in the appendix of this manual.

System Description

The Laser Pak III consists of a cryogenic liquid vessel, piping, vaporizer, and a patented high capacity
pressure builder. The product is mounted on a galvanized steel pallet for easy handling by forklift. A
galvanized steel frame encompasses the unit and protects it during transport.

A 393 liter liquid capacity (437 liter gross capacity) cryogenic vessel is included in the system. The vessel
consists of a pressure vessel suspended inside a jacket. The space between the pressure vessel and the jacket
is evacuated and insulated with a micro-fiberglass / aluminum foil radiation shield. Both the inner pressure
vessel and vacuum jacket are constructed of type 304 stainless steel. The vessel is designed and constructed in
accordance with DOT-4L and may be legally transported by truck in the United States while containing
product.

Piping circuits allow the vessel to vent, fill, pressurize, and provide pressurized gas. Piping is type-304
stainless steel. Valves are brass. Fittings are machined from forged brass or type-316 stainless steel. The
vaporizer and pressure builder are constructed of aluminum.

Instrumentation consists of a pressure gauge and a differential pressure gauge. The pressure gauge allows the
vessel pressure to be monitored. Accurate measurement of the vessel contents is provided by the differential
pressure gauge.

The Laser Pak III pressurizes cryogenic liquid by adding heat to the liquid in a controlled fashion. All energy
for building pressure is provided by heat from ambient air. The pressure builder design is protected by United
States Patent Number 6,276,143.

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PIPING CIRCUITS

The following paragraphs describe the operation of the piping circuits of the system. The descriptions refer to
the main components of each circuit and are grouped by function. Reference the piping schematic below and
in the general arrangement drawing for the component designations. These component and circuit
descriptions should be understood before attempting operation.

SV-1

SV-3

PVC-2

-

PI-1

V-2

PVC-1

VC-1

-

V-3

R-2

PVC-1

CV-1

LI-1

V-7

V-4

-

-

­CN-1

SV-2

FSV-1

CN-2

V-5

PBC-1

Legend

CN-1 Pump / Top Fill Connection SV-2 Safety Valve, 500 psig
CN-2 Gas Withdrawal Connection SV-3 Safety Valve, 22 psig
CN-3 Vent / Trycock Connection V-1 Valve, Pump / Top Fill
CN-4 Liquid Connection V-2 Valve, Vaporizer Isolation
LI-1 Liquid Level Gauge V-3 Valve, Pressure Building
PI-1 Pressure Gauge V-4 Valve, Vent / Trycock
PBC-1 Pressure Building Coil V-5 Valve, Gas Withdrawal
PVC-1 Pressure Building Regulator V-6 Valve, Isolation
PVC-2 Economizer Regulator V-7 Valve, Liquid
R-1 Safety Disc VC-1 Vaporizer Coil
R-2 Outer Casing Safety Disc FSV-1 Fill Stop Valve
SV-1 Safety Valve, 500 psig CV-1 Pump / Top Fill Check Valve

Figure 1: System Piping Schematic

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Fill and Vent Circuits

The liquid valve (V-7) communicates with the bottom of the vessel. A stainless steel tag labeled “LIQUID”
identifies the valve and the liquid connection (CN-4). Liquid is added or removed from the vessel through
this connection and valve.

The vent / trycock valve (V-4) is attached to a vertical tube in the upper portion of the vessel. The open end of
the tube is positioned at 90% liquid level based on the vessel volume. Opening the vent valve reduces
pressure in the vessel during filling. It also severs as a “full trycock”, venting liquid from the vessel when the
liquid level exceeds 90%. A tag labeled “VENT” is attached to this valve.

V-7

CN-4

V-4

CN-3

Figure 2: Fill and vent circuits highlighted in blue.

(Frame omitted from view for clarity.)

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Express Fill Circuit

The Express Fill circuit may be used for filling from the Taylor-Wharton Express Truck or for top filling by a
cryogenic pump. The pump / top fill valve (V-1) is a quarter-turn ball valve permitting filling of the vessel. A
check valve (CV-1) prevents product from escaping should the pump / top fill valve be opened inadvertently.

A fill stop valve (FSV-1) within the vessel prevents over filling. This device functions when filled by the
Taylor-Wharton Express Truck in automatic fill mode. The fill stop valve will not function when the vessel is
filled by a typical cryogenic pump.

CV-1

V-1

CN-1

Figure 3: Express Fill circuit highlighted in blue.

(Frame omitted from view for clarity.)

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Pressure Building Circuit

The pressure building circuit serves to build pressure after filling the vessel. The circuit is also used to ensure
sufficient driving pressure during high product withdrawal periods. Opening the pressure building circuit
valve (V-3) permits the circuit to function. A stainless steel tag labeled “P.B.” is attached to the valve. When
the pressure inside the vessel drops below 450 psig, the pressure building regulators (PVC-1) begin to open.
Two pressure building regulators are used to maximize performance. The regulators open fully at 400 psig.
This creates a path from the liquid in the bottom of the container to the gas space in the top. This path
contains a pressure building coil (PBC-1) to vaporize product as it flows from the bottom to the top of the
vessel. Liquid is expanded to a vapor and pressure is increased in the vessel. This pressure building circuit
design is protect by United States Patent Number 6,276,143.

PVC-1

PBC-1

V-3

PVC-1

PBC-1

Figure 4: Back-view showing the pressure building circuit highlighted in blue.

(Frame omitted from view for clarity.)

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