ASTM E Tolerances have been converted from avoirdupois to metric and rounded to two significant figures. Nominal Size. Class 0. Class 1. Class 2. services. The weight portfolio covers both OIML and ASTM weights from ASTM weights are available in classes 1 – 6 matching requirements of ASTM E International Organization of. Legal Metrology Recommendation R Troemner UltraClass Series. ANSI/ASTM E NIST Handbooks**. Weight. Class. E0*.
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If you feel that your comments have not received a fair w617 you should make your views known to the ASTM Committee on Standards, at the address shown below. Two-piece construction means the weight is made of multiple pieces of raw material. Nominal value of weights ast and below are determined by their shape as listed in the table below: Thank you for interesting in our services. Work Item s – proposed revisions of this standard.
Otherwise, due to their one-piece design, Class 0 weights will not maintain their measured value within the tolerance class. Periods shall not be used with abbreviations in marking weights. The knob has a thread that screws into the body and is tightened.
Your comments will receive careful consideration r617 a meeting of the responsible technical committee, which you may attend. As lower precision of measurement is required, so the range of density is broadened. A larger uncertainty cannot be arbitrarily chosen. This coating shall withstand shocks and outdoor weather conditions.
Weight bottoms are slightly recessed to expose the smallest possible area to wear.
If the values of all local measurements of magnetization and susceptibility are less than these limits, then asrm may be assumed that the uncertainty components due to the magnetism of the weight are negligible.
NOTE 4—Materials used to make weights for special applications that do not fall within the density limits stated above, should have stated densities or density determinations performed. Please copy and paste this embed script to where you want to embed Satm Script. Maximum Permissible Errors 4.
Troemner Calibration Weights 1 g and larger consist of a body and a lifting knob. The mass of the weight is the assigned nominal value plus the assigned correction. A precise measurement of density can only be made for one-piece weights. The lifting knob is specifically designed for use with forceps, tweezers or some other lifting device. Weight specifications are designed so the specifications e61 surface finish, markings, construction, material density and magnetic properties get more restrictive as the weight tolerances get smaller in order to enable the weight to maintain its tolerance over time.
If the weights satisfy the requirements of this standard, the uncertainty due to magnetism, uma, may be assumed to be zero.
This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years and if not revised, either reapproved or withdrawn. If magnetic effects are negligible, i.
This unique material possesses low magnetic susceptibility, uniform consistency and high resistance to corrosion. For weights which have sealing caps, the cap may be made of aluminum. It is the finest grade of stainless steel available and is similar to material originally specified in the manufacture of state primary standards. Sheet metal weights or wire weights may be used below 1 g. There is a cavity below the knob thread in the body which contains adjusting material, typically the same material from which the weight is made.
Elements for confirming metrological traceability to be an unbroken chain to an international measurement standard or a national measurement standard IPK or NPSshall include a documented measurement uncertainty, a documented measurement procedure, accredited technical competence, metrological traceability to the SI, and established calibration intervals see current VIM: Milligram Wire Weights – Troemner Calibration Weights mg and below are also available in wire construction as opposed to sheet metal with the shape denoting the nominal value as listed in the following table.
The acceptable maximum values for user markings are given in Table 7. The weights are manufactured of the finest stainless steels available including Troemner Alloy 8 Stainless Steel, which was developed by Troemner and is available exclusively through Troemner. Permission rights to photocopy the standard may also be secured from the ASTM website www. Other cylindrical class 6 and 7 weights of 5 kg or greater shall be made of grey cast iron or of another material whose brittleness and resistance to corrosion is similar or better than that of grey cast 5.
For weights of higher precision, the range of density is limited to values at or near the density of well-established standards, such as are used by primary calibration laboratories. One may be tempted to purchase the weights with the tightest tolerances in order to reduce measurement uncertainty.
ASTM E – 18 Standard Specification for Laboratory Weights and Precision Mass Standards
The surface requirements shall be met at the end of the adjustment process. Maximum permissible error, magnetic property, density, and surface roughness for each weight shall be within the limits indicated in this specification.
Wood cases for individual weights are available for weights 1 g and larger. All weights shall be free of ragged or sharp edges or ends. These handcrafted cases feature a fine wood exterior with an interior compartment that is either fully lined with padded velvet or velour for the given weight or the case has a foam interior.
Depending on the class, these weights may or may not be marked with their nominal value. Troemner UltraClass weights can also be used to calibrate Class 1 weights.
United States Download From http: Troemner weight sets where the largest weight is g and lower are supplied in attractive, durable polypropylene cases with a compartment for each weight within the case.
Troemner 7008-00 Alloy 8 Metric Stainless Steel ANSI/ASTM E617 Class 0, 20 kg
These weights are constructed with one end turned up to allow for easy handling with forceps. If it can be assumed that the type B uncertainty estimates are conservative with infinite degrees of freedom, the formula has the form: This may be interpreted as an eccentric loading error and the corresponding uncertainty should be estimated using Eq This is an upper limit for the uncertainty.
Markings shall not perforate or crack sheet metal weights. Referenced Documents purchase separately The documents listed below are referenced within the subject standard but are not provided as part of the standard. For Classes 5, 6 and 7 the total surface areas should be minimized to the extent possible. From the context it is usually clear in which sense the term is used. For these classes of weights, if the standard astj of mass difference measurements is not known from historical data, it can be estimated as: