Attachment C - Technical Specification for the EIC HSR BPM Button Assembly.pdf

Electron-Ion Collider, Brookhaven National Laboratory

Doc No. EIC-ISG-SPC-005 Author: R. Hulsart Effective Date: October 17, 2024 Review Frequency: N/A

Specification Title: EIC HSR BPM Button Assembly Revision: 03

TECHNICAL SPECIFICATION

for the

EIC HSR BPM Button Assembly

Quality Classification: A2

Prepared by:

__________________________________________ Date: __________________ Robert Hulsart, C-AD Instrumentation Engineer Collider-Accelerator Department Brookhaven National Laboratory

Reviewed By:

Joseph Tuozzolo, Technical Division Group Leader Electron-Ion Collider

David Gassner, EIC Instrumentation Group Leader

Matthew Paniccia, C-AD Instrumentation Engineer Collider-Accelerator Department

Charlie Hetzel, EIC Vacuum Group Leader Electron-Ion Collider Brookhaven National Laboratory

Docusign Envelope ID: 95A9A06B-3645-4993-9845-42FE0058D8DA

10/17/2024

10/17/2024

10/17/2024

10/17/2024

10/21/2024

Joe Zipper, Quality Assurance

Chuck Schaefer, ESH

Cindy Galdamez, Procurement Liaison Engineer

Approved By:

Vadim Ptitsyn, HSR L2 Manager

Docusign Envelope ID: 95A9A06B-3645-4993-9845-42FE0058D8DA

10/17/2024

10/17/2024

10/19/2024

10/21/2024

REVISION HISTORY

Revision # Effective Date Summary of Change

00 9/25/2023 Initial Release

01 2/6/2024 Added option for solid copper button, added two plating related document references, and made a few other minor edits/corrections.

02 5/29/2024 Added option for reducing the gap size between the button, and the collar around the button outer edge.

03 10/17/2024

Changed connector type to RP-SMA Female. Replaced Spec CAD-1119 with more recent EIC-VSG-SPC-023 in the

Document Table. Updated format and wording for better clarity

Table of Contents

1 SCOPE

1.1 Background

2 APPLICABLE DOCUMENTS

3 REQUIREMENTS

3.1 Technical/Performance Characteristics

3.1.1 Electrical Requirements

3.1.2 Vacuum Requirements

3.1.3 Mechanical Requirements

3.2 Materials

3.2.1 Hazardous Materials

3.2.2 Materials

3.3 Marking and Serialization

3.3.1 Serial Numbers

3.3.2 Part Numbers

3.4 Packaging/Shipping

4 VERIFICATION

4.1 Classification of Inspections

4.1.1 Pre-production Units

4.1.2 Acceptance Tests

LIST OF ACRONYMS

AISI American Iron and Steel Institute ASTM American Society for Testing and Materials ATP Acceptance Test Procedure BNL Brookhaven National Laboratory BPM Beam Position Monitor

BSA

C

Brookhaven Science Associates Celsius

CF ConFlat® (Vacuum Flange Type) Cu Copper EIC Electron-Ion Collider ESH Environment, Safety and Health HSR Hadron Storage Ring OFE Oxygen-Free Electronic RF Radio Frequency RP-SMA Reverse Polarity Sub-Miniature version A connector RRR Residual Resistivity Ratio UHV Ultra-High Vacuum VDC Volts Direct Current VSWR Voltage Standing Wave Ratio

Technical Specification for the EIC HSR BPM Button Assembly

1 SCOPE

This specification defines the technical requirements for the Hadron Storage Ring (HSR) Beam Position Monitor (BPM) Button Assembly to be used at the Electron-Ion Collider (EIC) at Brookhaven National Laboratory (BNL) managed by Brookhaven Science Associates (BSA).

1.1 Background

The EIC Project will design, build, and install the accelerator hardware for a new electron storage ring, a new electron accelerator synchrotron ring with an electron injector, and modifications to the hadron storage ring required to produce an electron-ion collider and associated infrastructure.

It will include one interaction region with a complete detector. The EIC is being designed to reserve space for a second interaction region with a second detector. The facility is designed to meet requirements to ensure high reliability and availability for the user program.

The HSR BPM Button Assemblies (Button Assemblies hereafter) will be procured by BSA for installation in the HSR of the EIC. The Button Assemblies will be an integral part of the HSR beam pipe vacuum envelope and will be used to carry radio frequency electrical signals from the interior vacuum region of the storage ring to the cryostat insulating vacuum region.

2 APPLICABLE DOCUMENTS

The following specifications, standards and drawings form a part of this specification to the extent specified herein. Unless otherwise specified, the issues of these documents shall be those in effect on the date of the solicitation or contract. Exceptions must be approved in writing by BSA.

In the event of a conflict between the applicable documents and this specification, the Contractor shall immediately notify the BSA Contractual Representative who shall in each instance determine which document takes precedence and advise the Contractor accordingly. Failure to notify BSA of a document conflict shall not relieve the Contractor’s responsibility to ensure full compliance with all requirements.

Document Number Document Title

2551M0003 Drawing for Hadron Storage Ring, Beam Instrumentation, 18 mm Button BPM

EIC-VSG-SPC-023 Technical Specification for the Design and Fabrication of Components for use in the EIC Vacuum System

MIL-STD-348B Specification for Radio Frequency Connector Interfaces

MIL-PRF-39012F Specification for Radio Frequency Coaxial Connectors

MIL-C-14450B Class 0 Copper Plating

ASTM Standard B571 Standard Practice for Qualitative Adhesion Testing of Metallic Coatings

29 CFR 1910.1200 Hazard Communication

BNL-QA-101 Brookhaven National Laboratory Supplier Quality Assurance Requirements

3 REQUIREMENTS

3.1 Technical/Performance Characteristics

Table 1: Technical Specifications for Button Assemblies

Physical Characteristics

Characteristic Specification

Operating Environment 4 Kelvin to room temperature <10-10 Torr. (UHV)

Connector RP-SMA Female

Housing Material Stainless Steel AISI 316L

Button Material Solid Cu 101/102, or Cu-Plated 316L

Electrical Characteristics

Characteristic Specification

Voltage Rating ≥700 VDC at 60 sec

Leakage Resistance >107 ohms at 500 VDC

VSWR Less than 1.2:1 from 20 MHz through 3 GHz

Contact Resistance ≤4 mΩ

Button Capacitance Variation, Assembly to Assembly Less than 10%

3.1.1 Electrical Requirements

3.1.1.1 Voltage Rating – The Button Assembly shall be capable of holding off at least 700 VDC from the center pin to the flange for 60 seconds duration.

3.1.1.2 Electrical Leakage Resistance – The electrical resistance from the Button Assembly center conductor to the outer housing shall be greater than 107 ohms at 500 VDC.

3.1.1.3 Impedance – The characteristic impedance for the coaxial feedthrough region of the Button Assembly shall be 50 ohms. The coaxial feedthrough region of the Button Assembly is defined as the electrical path between the SMA connector and where the conductor pin meets the button. The degree of impedance mismatch shall be quantified by the Voltage Standing Wave Ratio (VSWR) which shall be less than 1.2:1 from 20 MHz through 3 GHz.

3.1.1.4 Contact Resistance – The maximum resistance through the center contact shall be less than or equal to 4 milliohms. The contact resistance shall remain less than or equal to 4 milliohms after 300°C bakeout.

3.1.1.5 Button Capacitance – Unit-to-unit variation of button capacitance as measured at 100 MHz, at the SMA connector shall be less than 10%.

3.1.2 Vacuum Requirements

3.1.2.1 Ultra-High Vacuum (UHV) Environment – The Button Assembly will be used in an UHV environment. The flange seal side will be exposed to the beam vacuum (<10-10 Torr). All design details, fabrication techniques, and materials shall be in accordance with this application, as specified in Specification EIC-VSG-SPC-023. The Button Assembly flange is to be used in conjunction with a copper ConFlat® (CF) gasket vacuum seal.

3.1.2.2 Bake-out – The Button Assembly shall be capable of baking to 300°C without developing leaks and without degradation of its electrical performance. All design details and materials shall be consistent with this application.

3.1.2.3 Cryo-Temperature – The Button Assembly shall be capable of maintaining UHV at 4 Kelvin without degradation of its electrical performance. All design details and materials shall be consistent with this application as specified in Specification EIC-VSG-SPC-023.

3.1.2.4 Leak Rate – The Button Assembly shall have a leak rate of less than 2×10-10 std. cc/sec He when tested with a helium mass spectrometer leak detector with a minimum sensitivity of 1×10-

10 std. cc/sec He, at room temperature and at cryogenic temperature. All leak checking shall be carried out in an UHV-compatible clean environment using oil-free roughing pumps, as specified in Specification EIC-VSG-SPC-023.

3.1.2.5 Cleaning and Handling – During and after fabrication, all components shall be cleaned, free of hydrocarbon contaminants, and handled in accordance with their intended use in UHV systems, as specified in Specification EIC-VSG-SPC-023.

3.1.3 Mechanical Requirements

Mechanical configurations and tolerances shall be in accordance with drawing 2551M0003.

3.1.3.1 Environment – The Button Assembly shall have an operating range of 4 Kelvin to room temperature.

3.1.3.2 Connector – The Button Assembly connector shall be RP-SMA Female connectors built in accordance with MIL-PRF-39012F, Category A. The inner dimensions and interfaces of the SMA connector shall be in accordance with the MIL-STD-348B and shall be capable of mating with other connectors of the opposite gender for a minimum of 100 mating cycles.

3.1.3.2.1 Connector Material – The RP-SMA Female connector center pin shall be gold plated (nickel strike acceptable) or an alternative material approved in writing by the BSA technical representative.

3.1.3.3 Button material option – The surface of the button as indicated in drawing 2551M0003 shall be copper in order to meet the thermal design requirements of the assembly. The Contractor shall have the option to provide either a solid copper button (preferred) or a copper plated stainless-steel button. The method used to fasten the conductor pin to the button shall ensure a reliable mechanical connection that can withstand repeated thermal cycles over a temperature range of 4 K (-269°C) to 573 K (300°C).

3.1.3.4 Button Copper Plating Option

3.1.3.4.1 Plating Contractor Qualification – If the Contractor prefers to provide a copper plated button, BSA will recommend a qualified plating contractor that has demonstrated a plating method that can produce a copper purity high enough to meet the specifications and achieve a Residual Resistivity Ratio (RRR) greater than 10. The Contractor can suggest an alternate plating subcontractor. In this scenario, BSA will provide un-plated coupon blanks to that plating subcontractor. After several coupons are plated, BSA will test the plating characteristics to determine if the plating meets the specifications and RRR requirement. The alternate plating subcontractor can be used only after they are qualified and approved by BSA in writing.

3.1.3.4.2 Surface Plating Requirements - If the button will be copper plated it shall be plated as per MIL-C-14450 Class 0 and ASTM Standard B571 to the mechanical dimensions (thickness, tolerance) defined in drawing 2551M0003. The types of plating metal shall be 99.9% pure copper, with no brighteners or additives; the preferred material is copper C10100 or C10200 Oxygen-Free

Electronic (OFE). The plating metal choice, method, and subcontractor (if applicable), shall be approved by BSA in writing.

3.1.3.4.3 Plating Samples – If the button will be copper plated, BSA will provide un-plated sample coupons to be used as plating samples during the fabrication process of the pre-production and production units. The plated coupons shall be sent to BNL for testing to ensure the plating meets the specifications. Sample coupons shall be plated at the same time as the buttons using the same metal, method, and subcontractor (if applicable) as the plating for the button.

3.1.3.5 Button gap reduction option – The radial gap between the outer edge of the button and the surrounding collar is specified to be 0.020” on drawing 2551M0003, region D-4, and indicated as “RADIAL GAP”. As the gap is decreased from 0.020”, the performance of the button increases.

It is preferred that the gap be reduced from 0.020” to a gap that can be as small as 0.010”. It is understood that there are challenges during the fabrication process to provide a smaller gap that ensures concentricity between the button and the surrounding collar. The Contractor may propose a Button Assembly with a radial gap less than 0.020”. If so, the Contractor shall identify any additional cost for the gap reduction.

3.2 Materials

3.2.1 Hazardous Materials – Materials which may be defined as hazardous in accordance with 29 CFR 1910.1200, Hazard Communication shall not be used.

3.2.2 Materials – Written material certification shall be provided for each of the following materials. Materials used shall be non-magnetic.

• Button Assembly – All stainless-steel material shall be AISI 316L as per Specification

EIC-VSG-SPC-023.

• Solid copper button option – Copper C10100 or C10200 OFE material shall be used if solid copper is used for the button.

• Dielectric – The dielectric material used to electrically isolate the center conductor from the outer housing and to mechanically isolate the high vacuum side from the ambient atmosphere side and form a hermetic seal, shall be glass-ceramic (devitrified Si02 plus dopants) or alumina. The use of other materials shall be approved in writing by BSA.

• Insulators - The Button Assembly is to be used in a radiation environment with a maximum rate of about one megarad per year. All materials shall be consistent with this application. Use of Teflon® is specifically prohibited. Insulator materials shall be approved by BSA in writing.

• Conductor pin – The conductor pin that connects the button to the SMA connector shall be a material determined by the Contractor and shall be approved by BSA in writing.

• Conductor pin adapter – The detailed design, material used, and attachment method used for the male pin adapter that is attached to the end of the conductor pin shall be provided by the Contractor and approved by BSA in writing.

3.3 Marking and Serialization

3.3.1 Serial Numbers – Each Button Assembly shall be assigned a unique serial number by the Contractor. The serial number shall be laser engraved on the Button Assembly on the non-vacuum surface by the Contractor.

3.3.2 Part Numbers – Each Button Assembly shall be assigned BSA’s part number, as specified on the corresponding drawing. The part number and revision letter shall be laser engraved on the Button Assembly on the non-vacuum surface by the Contractor.

3.4 Packaging/Shipping

Each Button Assembly shall be individually packaged in a way to ensure protection during the shipping process and put into clean transparent polyethylene bags back-filled with clean, dry nitrogen. Knife-edge flanges and other vacuum-sealing faces shall be protected to prevent damage during transit. The Button Assemblies shall be shipped to BNL in boxes which are durable enough to facilitate subsequent storage at BNL after completion of incoming inspection. Plastic “peanuts” or other such loose packing material shall not be used by the Contractor in the packaging of the Button Assemblies.

4 VERIFICATION

Appropriate inspection/tests shall be performed to ensure unit conforms to all requirements in section 3 of this specification.

4.1 Classification of Inspections

Items covered by this specification shall be subjected to the following tests to determine compliance with all applicable requirements:

4.1.1 Pre-production Units

A set of pre-production Button Assemblies shall be fabricated and tested prior to the start of the fabrication of the production units. The pre-production units shall undergo the same acceptance tests as the production units, described in Section 4.1.2 herein. The Contractor shall not commence fabrication of the production units until receiving authorization in writing from BSA.

4.1.2 Acceptance Tests

4.1.2.1 Acceptance Tests Performed at Contractor - The Contractor shall submit Acceptance Test Procedures (ATPs) for BSA written approval that are in accordance with this specification and all reference documents noted herein. Each BPM Button Assembly shall be tested at the Contractor’s facility to demonstrate compliance with this specification. All data shall be documented and delivered to BSA for review prior to acceptance. In addition, the following tests shall be conducted on each Button Assembly at the Contractor’s facility in accordance with the ATP, prior to delivery to BNL:

• Dimensional Measurement – Dimensions of the Button Assemblies shall be measured for conformance to the drawing requirements. The list of required dimensions that shall be measured will be indicated in the BSA approved ATP.

• Cleanliness – The Button Assemblies shall be inspected for cleanliness and free of hydrocarbon contaminants, see section 3.1.2.5.

• Leak Checking – Shall be performed at room temperature in accordance with this specification.

• Surface Plating – If the button is copper plated, the plated portion of the Button Assembly shall be inspected to ensure a uniform plating thickness of plating metal, good plating adhesion, and no indication of pitting or flaking, see section 3.1.3.4.2.

4.1.2.2 Acceptance Tests Performed at BNL – In addition to the acceptance tests performed at the Contractor’s facility, the Button Assemblies will be acceptance tested at BNL. Any Button Assemblies that fail to pass these tests shall be returned to the Contractor for analysis and corrective action. The Contractor is responsible for incorporating any configuration changes if it is determined that the failure is caused by a design or manufacturing flaw. The Contractor’s responsibility includes shipping, labor, and materials.

• Electrical Tests - All the Button Assemblies will be tested for conformance with Section

3.1.1 of this Specification. Failure to meet the requirements of that section shall be grounds for rejection.

• Mechanical Tests – Mechanical dimension of the Button assemblies will be inspected to ensure they are within the tolerances shown on the drawing, and received all necessary markings as defined in section 3.3.

• Surface Plating – If the button is copper plated, the plated portion of the Button Assembly will be inspected to ensure compliance with tolerances shown on the drawing, see section

3.1.3.4.2. Thickness and adhesion measurements will be performed using the test methods called out in ASTM Standard B571. In addition, BSA provided unplated sample coupons that are plated by the plating Contractor at the same time as the button plating, then returned to BNL, will be inspected by BSA for thickness, adhesion, and Residual Resistivity Ratio

(RRR) >10, see section 3.1.3.4.2. Surface plating will be tested after cryogenic thermal cycling.

• SMA Connector Mating Tests - The SMA connector will be tested for conformance with the insertion and withdrawal force specifications in MIL-STD-39012F and MIL-DTL- 348B. The contact resistance will be measured before and after the test to verify conformance with Section 3.1.1.4.

• Cryogenic Thermal Cycling – The Button Assemblies will be thermal cycled multiple times (~10) from room temperature to cryo temperature. Electrical, mechanical, connector, copper plating, and leak checks will be done before, during, and after the sequence of thermal cycling.

• Leak Checking – Button Assemblies will be vacuum baked at >150°C for a minimum of one hour to remove water vapor prior to leak checking. Leak checking will be performed at room temperature and at cryogenic temperature with a Helium Mass Spectrometer leak detector to determine conformance with paragraph 3.1.2.4 of this Specification. Failure to meet the requirements of that paragraph shall be grounds for rejection.

• Cleanliness - The Button Assemblies shall be inspected for cleanliness and free of hydrocarbon contaminants, see section 3.1.2.5.

3.4 Packaging/Shipping