Precision Calibration Weights
Rice Lake Weighing Systems manufactures precision calibration weights, including all ASTM, OIML, and NBS classes, for balances and scales. We also provide special design weights, weight kits, and weight cases. Our precision weights are designed specifically to assist you with ISO 9000 traceability requirements.

Calibration Services
Our state-of-the-art metrology lab is accredited by the National Voluntary Laboratory Accreditation Program (NVLAP)* and provides quality weight services, including recalibration and refurbishing of existing weights. For all new and existing weights that need recalibration, we offer both Traceable and Calibration Certificates.

CAST IRON TEST WEIGHTS
Quality Guaranteed by the Toughest Standards of All… Our Own
Designed for scale calibration, our solid cast iron test weights are sealed to ASTM classes 6 and 7 specifications; Class F tolerances are listed in the National Institute of Standards and Technology Handbook 105-1. All weights are traceable to NIST. To verify adherence to class F tolerances, optional traceable certificates are available.

Our cast iron weights undergo a special phosphatizing process in which the metal is thoroughly cleaned and mildly etched to allow exceptional finish adhesion. The weights are then coated with a layer of chip-resistant paint which conforms to NIST Handbook 105-1 standards. This two-step process ensures a long-lasting finish that greatly reduces the possibility of corrosion.

Sartorius Calibration Weights And Certification

• NVLAP-accredited metrology laboratory
• 1 mg to 5 kilogram weights
• Single-piece construction
• Corrosion-resistant stainless steel
• Meet or exceed all ASTM standards
• Custom weight sets available

Calibration values vary over time due to changing conditions within the balance or the surrounding environment, such as temperature variations, gravitational forces, relocation of the balance, or aging of the balance's electronic components. Because of these changes, electronic balances must be calibrated with a mass standard upon installation and at regular intervals to ensure proper weighing and traceability.

Tradition of Quality:
Sartorius has been a world leader in weighing technology since 1871. From that time, Sartorius has led the way in the development and manufacturing of high precision mass measurement equipment. The mass standards produced by Sartorius today are designed to meet or exceed the standards of the American Society of Testing Materials (ASTM E617).

Single-piece construction:
Because the precise measurement of density can only be achieved using a single piece weight, all Sartorius weights are ASTM Type 1 single-piece weights. These weights contain no air cavity or foreign adjusting material, thus providing the maximum mass stability. In addition, it is an ASTM requirement that one-piece weights are used as standards and where mass stability is required.

A Choice of Preconfigured or Custom Weight Sets:
Whether you choose a preconfigured weight set, or have a custom set made to meet your specific needs, be assured that all Sartorius weights are made of the highest quality materials. Weight sets consist of flat weights in the 1mg to 500mg range and knob-style weights in the 1g to 100g range. Each 1mg thru 5mg weight is made of aluminum, while all other weights are constructed of stainless steel.

Which Class is Right for My Application?
A balance should be calibrated using a weight with a class tolerance factor greater than the readability of the balance. Example: A toploading balance with readability of 0.01g should be calibrated with a weight having a known tolerance of at least 0.009g.

Ultra-Class U Standards.
T hese mass standards provide the greatest precision available from Sartorius. They are ideal for use as reference standards to calibrate high-resolution analytical balances or to calibrate other weights. The Ultra-mass tolerances are approximately two times the precision of ANSI/ASTM Class 1.

ASTM Class 1.
Appropriate for the calibration of high-precision analytical balances. They can also be used as reference standards in calibrating other weights.

ASTM Class 2.
Appropriate for calibrating high-precision toploading balances with readabilities ranging from 0.001g to 0.01g. Sartorius Calibration Weights and Certification.