Instruction Manual

ManualsBrandsTaylor-Wharton ManualsEquipmentLiquid Withdrawal Device

LIQUID

WITHDRAWAL DEVICE

For Liquid Nitrogen

25LD, 35LD and

50LD Dewars

The Liquid Withdrawal Device (LWD) provides

convenient pressure transfers of liquid nitrogen from

25 LD, 35LD and 50LD Dewars. The device clamps

directly to the special neck flange that is found under

the plastic trim collar around the neck of these

containers.

Flow rates up to 8 liters per minutes are possible at

operating pressures up to 10 psig (0.7 bar/69 kPa).

Liquid can be dispensed directly from the LWD via

the spout provided, or through a standard cryogenic

hose connected to the liquid outlet.

Filling a Dewar is accomplished by pressure

transfer through the withdrawal device. (See

Filling Instructions.) This filling method allows

replenishment of the liquid supply in the Dewar

without removing the LWD, while keeping the liquid

saturated at a pressure sufficient to sustain liquid

withdrawal.

Safety

Before using this equipment, read these instructions

carefully. Also, read and understand the instructions

supplied with your Dewar and the Handle with Care

booklet packed with all Liquid Nitrogen Dewars.

The Handle with Care booklet (Form TW-10) gives

detailed information on the safe handling of liquid

nitrogen. Additional copies of these publications can

be obtained from your supplier. Do not modify LWD

or Dewar or use in a manner other than that described

in accompanying instructions and documentation.

Contact with liquid nitrogen or cold gas may cause

serious freezing (frostbite) injury. Do not touch

liquid or cold metal surfaces with your bare skin.

Always wear a face shield and gloves when transferring

liquid nitrogen.

Nitrogen gas can cause suffocation without warning.

In a confined area, nitrogen gas from this equipment

may displace air required for breathing. Store and use

this equipment only in well-ventilated areas.

Use only containers designed for low-temperature

liquids.

Cryogenic containers should be filled

SLOWLY to minimize stresses which can damage

the container

Vent all pressure from a Dewar before attempting

to remove the Liquid Withdrawal Device. If the

band clamp securing the LWD to a Dewar is loosened

while there is pressure in the Dewar, cold gas or

liquid could be expelled causing personal injury.

Liquid Withdrawal Device is for use with liquid

nitrogen only. LWD is for use on specific model

Taylor-Wharton Dewars listed above.

Pressure in Dewar with LWD installed should

never exceed 10 psi. Fill Dewar from supply source

at 22 psi or less. Do not pressurize using compressed

air.

TW-43

Summary of content (4 pages)

PAGE 1
TW-43 LIQUID WITHDRAWAL DEVICE For Liquid Nitrogen 25LD, 35LD and 50LD Dewars The Liquid Withdrawal Device (LWD) provides convenient pressure transfers of liquid nitrogen from 25 LD, 35LD and 50LD Dewars. The device clamps directly to the special neck flange that is found under the plastic trim collar around the neck of these containers. Flow rates up to 8 liters per minutes are possible at operating pressures up to 10 psig (0.7 bar/69 kPa).
PAGE 2
Installation 1. Remove the necktube cap/core from the Dewar 2. Remove 3 flat-head mounting screws in the base of the plastic trim collar around the neck of the Dewar, remove the collar and discard or save for later. It is not used while the LWD is installed. SCREW(3) COLLAR 5. Position the safety cable assembly around the top of the Dewar, underneath the flange. Loosen V-Band Clamp until the clamp is large enough to remove from the LWD. Drop the band clamp around the flange on the Dewar (see Figure 2).
PAGE 3
Operation Filling — It is not necessary to remove the LWD unit from the Dewar for filling. You may fill the Dewar by pressure-transfer of liquid nitrogen through the LIQUID valve of the LWD. WARNING: Over pressurization of the Dewar could result in serious bodily injury or property damage. Never exceed the 10 psig (0.7 bar/69kPa) relief valve pressure setting of the LWD. To fill, remove the spout assembly and connect a 22 psig (1.
PAGE 4
Replacement Parts 26 25 27 22 1 20 21 15 23 11 12 19 17 18 6814-9225 2 Valve (Liquid/Vent) 6986-9004 3 Valve Handle Cover, Liquid D050-8C18 4 Valve Handle Cover, Vent D050-8C19 5 O-Ring for valve 8830-6142 6 7 Pressure Gauge 0-30 psig (0-2 bar/207 kPa) Relief Valve 10 psig (0.7 bar/69 kPa) 7702-6091 6913-9044 Relief Valve 15 psig (1.