Attachment_1_NIST_Requirements.docx

NIST Requirements Document High Precision Mass Comparator System I. Background The measurement of mass in a vacuum environment is critical for support of the experiments involved in the redefinition of the unit of mass, the kilogram at the National Institute of Standards and Technology (NIST). The watt balance experiment (performed at the NIST) and the International Avogadro Coordination project will, for the first time in history, define the unit of mass in terms of the Planck constant, an invariant of nature. However, both experiments will take place in a vacuum environment. In order to disseminate the kilogram to the outside world, the physical effects, i.e., the gain and loss of mass due to moving a mass artifact in and out of a vacuum environment must be quantified.

II. Scope The requested system is required in support of a broader NIST program in the Quantum Measurement Division that will a) measure mass in terms of the Planck constant (watt balance); b) develop models for an artifact’s change in mass when going in and out of a vacuum environment (mass in vacuum system being requested), and; c) dissemination of the Planck constant-based kilogram from vacuum to air via a magnetic levitation mass comparison system (under development). A critical part of this program is the procurement of a state-of-the-art, self-contained, high precision mass-in-vacuum system for quantifying the effects of atmospheric contaminants on metallic mass standards.

III. Minimum Requirements This is a brand-name or equal acquisition for manufacturer Mettler-Toledo; 1900 Polaris Pkwy, Columbus, OH 43240-4035. Brand name or equivalent description is intended to be descriptive, but not restrictive and is to indicate the quality and characteristic of products that will be considered satisfactory to meet the agency’s requirement. All items must be new. Used or remanufactured equipment will not be considered for award. Experimental, prototype items will not be considered. The use of “gray market” components not authorized for sale in the U.S. by the contractor is not acceptable. All line items shall be shipped in the original manufacturer’s packaging and include all original documentation and software, when applicable.

Contract Line Item 0001: The contractor shall provide one (1) high precision mass comparator system for use in vacuum or atmospheric pressure air brand name or equivalent model M_One mass-in-vacuum comparator that meets the following salient characteristics:

1. Mass determination of weights from 1 mg to 1 kg

2. Resolution of 100 ng

3. Repeatability of 500 ng

4. Weight carousel (exchanger) capacity of six weights

5. Software that controls all aspects of data gathering for weighing designs that include up to six weights

6. Working vacuum level of 1 x 10-4 Pa or lower with 6 weights installed.

7. All required tables, supporting hardware, and vacuum components, including but not limited to fittings, 0-rings, nuts and bolts, and blank flanges

8. A minimum electrical weighing range of 1.5 g.

9. Built-in adjustment weight, software controlled.

10. Software must read environmental parameters (humidity, temperature, pressure) from third party instruments via standard computer port (RS-232) and use them to calculate air density as part of buoyancy corrections to measured apparent mass.

11. Automated centering of weights on carousel.

12. Carousel must accept all common mass shapes in stainless-steel, including cylindrical, OIML, and ASTM. Silicon spheres having a nominal mass of 1 kg and a diameter of approximately 10 cm must also be accommodated by the carousel and mass pan.

13. Vacuum system must contain a separately pumped load-lock for loading weights in air and reducing the pressure prior to inserting weights into vacuum chamber.

14. Load-lock must be compatible with existing NIST vacuum transfer system (drawings attached to this documentation below)

15. Vacuum chamber must contain at least 10 unused vacuum-compatible ports with flanges (NW or CF type) for auxiliary instrument connections.

16. If the vacuum enclosure contains a detachable belljar (i.e., for access to the mass balance), a motor-driven lifting mechanism must be provided.

17. The footprint of the instrument must not be larger than 240 cm x 120 cm in order to fit in the lab with required egress.

18. The load-lock provided for the main weighing chamber must be compatible with existing NIST-built hardware for transporting mass artifacts (see the drawings below for information on the existing NIST built-hardware).

19. The load-lock for the main weighing chamber must be able to receive an artifact from the NIST Mass Transport Vehicle and associated hardware provided by NIST. The Contractor shall provide technical drawings of the main weighing chamber load-lock as part of their quote to prove compatibility. This capability will be evaluated by NIST personnel prior to award.

NIST Load-lock and compatibility description The NIST load-lock is a six-way cross with ISO160 flanges. This load-lock is an intermediate station for a mass that is being transferred under vacuum conditions from an external transport vehicle. The NIST load-lock was designed and constructed to be compatible with an existing Mettler-Toledo M_One mass-in-vacuum comparator. The NIST load-lock allows a 1-kilogram mass to be transferred into the Mettler-Toledo load-lock, from which it can be loaded onto the M_One carousel inside the vacuum chamber. See Fig. 1 photo below. All pertinent parts are called out with red arrows; the three-step path followed in the process of removing a weight from the MTV and loading it into the Mettler-Toledo chamber is likewise traced in red.

Linear positioner #1

Travel Path NIST Load-lock

Linear positioner #2

Mettler-Toledo Load-lock

Fig. 1 Path of mass transfer from NIST MTV into the Mettler-Toledo M_One Chamber. Linear positioners are used to move a mass into or out of the NIST and Mettler-Toledo load-locks.

NIST has invested several years and commensurate funds in developing a universal load-lock system. It is universal in the sense that the same load-lock is attached to four different NIST apparatus that play complementary roles in realizing and disseminating the unit of mass based on the Planck constant. The NIST load-lock (Fig. 2) contains an intermediate transfer station for masses that are being transferred from the NIST Mass Transport Vehicle (MTV) to the Mettler-Toledo M_One load-lock. The NIST load-lock accepts a 1-kilogram mass (under vacuum or not) from the MTV using two linear positioners. The MTV interfaces with the NIST load-lock through an ISO160 flange. Linear positioner #1 is attached to the NIST load-lock and is used to retrieve the 1-kilogram mass from the MTV and to move it into the NIST load-lock and onto the temporary transfer station (Fig. 3). Once the mass is in the NIST load-lock, the MTV can be disconnected from the NIST load-lock. The 1-kilogram mass is next moved to the Mettler-Toledo load-lock using linear positioner #2; once in the Mettler-Toledo load-lock, Mettler-Toledo has a standard method for moving the mass into the chamber.

NIST is willing to provide the same auxiliary equipment to achieve compatibility with another mass-in-vacuum comparator. This auxiliary equipment is limited to (2) linear positioners, (2) gate valves, ISO nipples, a 6-way ISO cross, and intermediate transfer stations, such as those that were added to the NIST load-lock and the Mettler-Toledo load-lock. NIST is unwilling to engage in further engineering design work. No loss in mass comparator function or capability should occur as a result of adding this hardware. Accommodating the NIST MTV is an absolute requirement.

Gate Valve

NIST MTV

Fig. 2. Drawing of NIST MTV and NIST Load-lock. The NIST Load-lock is a six-way cross with ISO 160 flanges and contains a temporary transfer station, as shown in Fig. 3 below.

ISO 160 Flange

Fig. 3. Drawing of transfer from linear positioners. The Transfer Fork at the end of the linear positioner interleaves with the tines of the Transfer Station (intermediate transfer point). The transfer point itself moves vertically to remove the mass from the transfer fork.

IV. Delivery Delivery shall be FOB DESTINATION and shall occur NLT ten (10) months ARO.

FOB Destination means: The contractor shall pack and mark the shipment in conformance with carrier requirements, deliver the shipment in good order and condition to the point of delivery specified in the purchase order, be responsible for any loss of and/or damage to the goods occurring before receipt and acceptance of the shipment by the consignee at the delivery point specified in the purchase order; and pay all charges to the specified point of delivery. The contractor shall deliver all Line Items to:

The National Institute of Standards and Technology 100 Bureau Drive, Building 219 Rm. G003 Gaithersburg, MD 20899-1640

V. Installation and Training Contract Line Item 0002: Installation:

The system shall be installed by the Contractor and meet contract specifications no later than 30 days after delivery. Installation, at a minimum, shall include uncrating/unpackaging of all equipment, rigging, set-up and hook-up of the system, demonstration of all specifications, and removal of trash. Onsite installation and demonstration shall be done at NIST, Gaithersburg, MD lab 219/G003.

The contractor shall conduct a training session for up to three (3) users at NIST. The training shall provide a thorough demonstration of all system/solution functions, maintenance, data administration, and basic troubleshooting. The training may be completed at NIST immediately after installation/set-up and on-site measurements demonstrating that no damage or misalignment issues arose during transportation and installation, but shall be completed no later than five (5) days after installation.

VI. Inspection and Acceptance In addition to the inspection and acceptance terms articulated in 52.212-4, the Government reserves the right to perform such performance tests and evaluations as defined below to verify specified system performance. Such tests and evaluations, if performed, shall be conducted within the environment that the system is to be operated. The Contractor has the right to be present during the tests and evaluations, if performed, at the Contractor’s expense. Inspection tests shall include:

1. Verify the resolution of the system as specified (0.1 micrograms)

2. Verify vacuum capability of system (10-6 mbar)

3. Verify operation of vendor-supplied software

4. Verify all measurement specifications can be met with NIST weights in a 4 -1 weighing design for 1 kg mass artifacts.

These tests shall be performed with NIST mass artifacts that are known to have good mass stability. Standard deviations of multiple mass comparisons at the one kilogram level will be used to test the capability of the instrument. Contractor will demonstrate all steps in the comparison calibration process for 1 kg artifacts, including pumpdown and venting of the vacuum chamber. Compatibility with existing Mass Transfer Vehicle hardware must be demonstrated at the time of installation.

A visual inspection of the high precision mass comparator system will be performed by the NIST Technical Point of Contact (TPOC)/ Contracting Officer Representative (COR) to identify surface defects or any form of indication that the high precision mass comparator system was damaged during transport to NIST. The Government shall have sole discretion to require repair or replacement of damaged and/or nonconforming supplies at no cost to the Government. The Government at any time prior to acceptance shall reject the high precision mass comparator system due to defects and/or nonconformance. Ownership (title) of the high precision mass comparator system shall transfer to NIST upon acceptance.

VII. Warranty The contractor shall warrant the entire system for a period of at least one (1) year. The warranty must include unlimited telephone/e-mail support for questions regarding operation. All costs including parts, labor, travel, and other expenses necessary to repair the system will be borne solely by the contractor at no additional cost to the U.S. Government. Warranty shall commence upon acceptance.

VIII. Payment Schedule The Contractor shall be paid, in accordance with Net 30-day payment terms, upon receipt and acceptance of a proper invoice, in accordance with the following schedule:

1. 100% after receipt and acceptance by the TPOC/COR of fully delivered, installed, and training is complete for the system.

1. The Government anticipates inspection will occur upon:

1. After the testing procedures set forth in this document have been complete NOTE: Proposed payment schedules shall be submitted with vendor’s response to the RFQ for consideration.

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