Test Method: D2983, ISO 9262, IP 267
Programmable Liquid Visibility Bath for Brookfield Viscosity at Low Temperatures
• Programmable Liquid Visibility Bath for Brookfield ....Viscosity at Low Temperatures
• Superior data reproducibility and repeatability vs. air ....chamber method
• Replaces the need for balsa wood carriers
• Operating temperature range from +20° to -55°C
• Temperature stability better than ±0.1°C
• Full visibility of the immersed sample
• One and two independent bath models
Click for AIR CHAMBER BATHS
Click for Liquid Baths Controller Upgrade
Click for Sample Heat Preconditioning Heated Baths

The use of programmable liquid baths for ASTM D2983 has been allowed since the first development of the test if the cooling profile meets the specifications of Annex A2 of the method.

The Lawler liquid baths are programmed such that the sample cooling rate equals the cooling rate experienced by a sample when immersed in the constant low temperature air chamber. The bath can also be programmed to cool at a rate of 1°C per minute from ambient to as low as -55°C as per CEC-L-18A, ISO 9262, and IP 267 for the measurement of European low temperature Brookfield viscosity.

Operating temperature range of the programmable liquid baths is +20° to -55°C. Temperature control is within ±0.1°C. Windows based PC proprietary software is capable of controlling two baths simultaneously. This allows operating baths at two independent temperatures with independent start, stop, and duration times.

The bath is an unsilvered Dewar jar holding about 3 liters of bath medium. The illuminated jar allows full visibility of the test samples to facilitate the proper position of the spindle bead immersion level.

The turntable holds 10 test samples. After the 16 hours conditioning time, the turntable is manually rotated until the proper test cell is under the viscometer. The spindle is connected while the sample is still in the liquid bath. This allows the measurement of viscosity without removing the sample from the temperature controlled environment. Far superior viscosity data repeatability is obtained using this procedure as opposed to the air chamber procedure.

Duplicate samples at -40°C were measured in a Model 76 Liquid Programmable Bath. Of the 56 samples, the average variability between the duplicate samples was ±1.13% of mean. This compares very favorably to the method’s stated precision of 11.8%. The key factor in this improved precision is the superior temperature control of the sample as its viscosity is being measured. 

Model LB-76 Programmable Liquid Bath is a bench top model has a single bath with 10 sample capacity. A Windows based PC is required (not supplied). The bath is supplied with an integral leveling viscometer support rod.

Model LB-76-2 is a bench top model and is identical to Model LB-76 but with two independently controlled baths, each with 10 sample capacity. This allows two simultaneous tests at different temperatures, and independent start and/or stop times.

Model LB-76-2G is a identical to Model LB-76-2 but configured as a floor model.


Available Models
Model No.
No. of Baths
Sample Capacity
Lowest Temperature
Cabinet Dimensions
Ship Weight lbs/cu.ft
LB-76
1
10
-55ºC
23x24x27
(58x61x69)
300/28
LB-76-2
2
20
-55ºC
27x34x25
(68x85x63)
440/32
LB-76-2G
2
20
-55ºC
27x34x25
(68x85x63)
440/32
KVS-1
Table for Model LB-76

Options for Above Models
Part No.
Description
LM-PC
Lawler supplied computer configured with software. Specify PC or laptop
UR-PC
Customer supplied computer configured by Lawler
PCD
Drawer for laptop PC or keyboard
KVS-1
Floor stand for Model LB-76
KVS-2
Floor stand for Model LB-76-2

Accessories
Part No.
Description
92-10
Dry block bath for sample preconditioning, 10 test positions, optional
92-20
Dry block bath for sample preconditioning, 20 test positions, optional
LVDV II+Pro
Brookfield digital viscometer and DV configuration software
LB-VR
Viscometer clamp assembly (included with visc. purchased from Lawler)
Wingather
Data capture software from Brookfield
#4B2
Insulated viscometer spindle, each
LB-F
Test cells, per dozen. (Do not use air chamber test jars)
LB-Z
Test cell stopper, each
LB-K
Test cell cover, each
N27B
Reference Fluid, pint -40°C to -18°C (37,000 cP @ -40°C)
N115B
Reference Fluid, pint -29°C to - 7°C (12,000 cP @ -12°C)
N14B
Reference Fluid, pint 17,000 cP @ -40°C
N60B
Reference Fluid, pint 150,000 cP @ -55°C
N120B
Reference Fluid, pint 150,000 cP @ -40°C
N480B
Reference Fluid, pint 150,000 cP @ -26°C
N1400B
Reference Fluid, pint 150,000 cP @ -12°C
UPG-1
Upgrade kit for converting older Model LB-76 to PC Control
UPG-2
Upgrade kit for converting older Model LB-76-2 to PC Control
LB76-Kit
Recommended Accessories for LB76 or LB76-G. Includes:
(2) LB-F, (10) LB-Z, (14) #4B2, (10) LB-K, (1) LM-PC
LB76-2-Kit
Recommended Accessories for LB76-2 or LB76-2G. Includes:
(3) LB-F, (20) LB-Z, (25) #4B2, (20) LB-K, (1) LM-PC
Note1: Kits do not include Brookfield Viscometer, purchased separately

Note2: Recommended are at least 2 reference fluids for each desired test temp./visc.



Specifications are subject to change without notice.

Specifications subject to change without notice. Lawler Manufacturing Corporation © 2011