SOW_80JSC021QTVC0.pdf

1. Purpose

The objective of this effort is to implement dusty thermal vacuum testing capability for testing components/subsystems in a simulated lunar environment. This includes testing test articles in a thermal vacuum environment in a bed of lunar regolith or dusted with multiple layers of regolith.

2. Scope

This document defines the specifications required for the thermal vacuum chamber being procured by NASA Johnson Space Center (JSC). The equipment design will consider the OSHA, NEC and ASME Code for Unfired Pressure Vessels. Safety interlocks and features will be provided for the equipment and operating personnel. The equipment shall be tested prior to shipment, with results provided in the form of a report.

3. References

All references are assumed to be the latest version unless otherwise indicated.

ASME BPV Code, Boiler and Pressure Vessel Code, Sections II, V, VIII, and IX

ASME B31.3 Process Piping

ASTM A240 Standard Specification for Chromium and Chromium-Nickel Stainless

Steel Plate, Sheet, and Strip for Pressure Vessels and General

Applications

ASTM A312 Standard Specification for Seamless and Welded Austenitic Stainless

Steel Pipes

ASTM A380 Practice for Cleaning, Descaling, and Passivation of Stainless Steel

ASTM A403 Standard Specification for Wrought Austenitic Stainless Steel Piping

Fittings

ASTM E498 Standard Test Methods for Leaks Using the Mass Spectrometer Leak

Detector or Residual Gas Analyzer in the Tracer Probe Mode

NFPA 70 National Electrical Code

SNT-TC-1A ASNT’s guideline to personnel qualification and certification in NDT

SQP-5300-0016 Certification of NDT personnel

Dusty Thermal Vacuum Chamber

Statement of Work

The following items are required for the proposed system:

4. Physical/Dimensional Design

4.1 Chamber form factor shall be a cube-type design.

4.2 The system shall fit within 4’ wide x 7’ tall doorway in order to be moved into the test facility.

4.3 Size of assembled test system shall be no more than 9’ length x 6’ depth.

4.4 The chamber’s internal volume shall be a minimum of 36” wide by 36” long by

36" high.

Rationale: The volume specified accommodates a 24” wide x 24” long x 24” high test article volume plus margin.

4.5 The system chamber volume shall be no larger than 100 ft3.

Rationale: The maximum exempt volume for a vacuum vessel is 100 cu ft.

ASME/ NB stamps are not required below this volume for vacuum vessels.

5. Mechanical Design and Construction

5.1 The chamber, including but not limited to the body and door, shall be designed of Type 304 stainless steel plate in accordance with the ASME Code, Section VIII, for Unfired Pressure Vessels.

Note: Design is in compliance with ASME Code, Section VIII, for Unfired Pressure Vessels but does not imply fabrication is per ASME Code, Section VIII, for Unfired Pressure Vessels.

5.2 The outer structural shell of the environmental simulator shall be designed to resist one atmosphere of external pressure while under vacuum.

5.3 Penetrations, nozzles, and door hinges shall be of Type 304 stainless steel conforming to ASTM-A240, A312, or similar specifications subject to customer review and approval.

5.4 Chamber door shall have a handle adequate to manually open the door.

5.5 Internal chamber body shall be electropolished and passivated (required for working pressure of 10e-6 torr and below to support cleaning).

5.6 The system door closure shall contain a latching feature that can withstand up to 3 psig of internal pressure.

5.7 The door shall be front loading and hinged on the left side when facing the front of the chamber.

5.7.1 Shall be capable of opening a full 180 degrees swing to allow maximum access.

5.8 The door entry area shall be minimum 36” by 36”.

5.9 The door shall be sealed to the chamber with a minimum of one Viton O-ring(s).

5.9.1 The chamber side of the door interface shall have dovetail O-ring groove(s).

5.9.2 For a more than one O-ring door seal, a port shall be provided for pumping the annulus in between the O-rings.

5.10 The top of the base plate shall be approx. 32” from customer finished floor.

5.11 The system shall be able to support greater than or equal to 150 lb of test hardware.

5.11.1 The base plate shall support 150 lb. mass load.

5.12 The vacuum chamber shall be provided with a fixed in place open-loop thermal conditioned shroud.

5.12.1 The shroud surface shall be traced with passages to accommodate LN2 which will perform the thermal conditioning function.

5.12.2 The shroud shall fully encapsulate the test specimen area, including the ends.

5.13 The thermal shroud shall be optically dense.

5.14 Thermal shroud inside surface shall be painted with a low-outgassing, solar-absorbing (high emissivity) black paint.

5.15 The portions of the shroud facing the customer product are coated in a high emissivity aerospace black paint to absorb product heat load.

5.15.1 The paint shall have a total hemispherical emissivity of greater than 0.85 at room temperature to increase the radiative coupling to the inner test articles.

5.16 The shroud/ thermal system shall be constructed per ASME B31.3.

5.17 The following documentation shall be provided:

Weld procedure specifications (WPS) Braze procedure specifications

Procedure qualification record (PQR) Welder performance qualification (WPQ) Braze performance qualification B31.3 weld inspection record

B31.3 Braze inspection record B31.3 pressure test record

5.18 The chamber weld design shall eliminate virtual leaks.

5.19 Any hoses shall be provided with pressure test reports.

5.20 The exterior portion of the shroud is polished.

5.21 The chamber shall have ports for chamber instrumentation and control.

5.22 The chamber shall have ports for chamber pumping system.

5.22.1 The chamber port for the turbomolecular pump shall be located such that the pump inlet is facing down towards the ground.

5.23 The chamber shall have ports for chamber thermal shrouds and base plate.

5.24 All corresponding customer port holes and vacuum equipment access shall be detailed on the approval drawing prior to construction.

5.25 The chamber shall include a total of eight ConFlat (CF) Ports not utilized by any instruments or gauges:

5.25.1 Seven 2 ¾” CF ports with 1.5” Tube OD.

5.25.2 One 6” CF port with 4” Tube OD.

5.25.3 All feedthrough ports shall enter chamber without altering configuration of the shroud.

5.25.4 Ports shall be furnished with blank flanges.

5.26 The chamber and thermal shroud surfaces shall be visibly clean and free of grease and fabrication debris.

5.27 All construction material used shall be vacuum compatible.

5.28 All O-rings exposed to vacuum shall be Viton.

5.29 High vacuum gauges shall be provided (Baratron, Granville Phillips or Cold Cathode)

5.29.1 Vacuum sensing measurements shall be compatible with or protected from dusty atmosphere.

6. Thermal Performance

6.1 If thermal conditioning fluids are required for operation, they shall be non-combustible, non-toxic, and documented in the bid proposal and approved prior to contract award.

6.2 The thermal shroud and base plate shall be designed with fluid shut off valves and separable fluid fittings/joints to allow for ease of removal and replacement.

6.3 Thermal shroud shall be thermally separated from the base plate.

6.4 Heated/Cooled Thermal Base Plate, Polished AL.

6.4.1 Temperature Range: -196 °C to +150 °C.

6.5 Thermal conditioning LN2 requirements

6.5.1 VCR tube fittings shall be used for fluid interconnect lines.

6.5.2 Equipment can operate as specified with LN2 supply of 1/2 inch diameter tubing at 100 psig (equipment rated for 100 psig minimum).

6.6 Temperature ramp rate of the shroud shall go from -196 °C to +150 °C or +150 °C to -196 °C within an hour.

6.7 Each thermal shroud panel and baseplate shall have a minimum of 4 Type -T

Thermocouples.

6.8 The Systems internal temperature control tolerance shall be ±1°C at any steady state temperature condition measured at base plate (or shroud) after stabilization.

6.9 Less than 2 °C gradient across shroud surface.

Rationale: Homogeny across thermal shroud is a critical requirement for some hardware that will be tested.

6.10 PID Controller PM4 with TC input for thermal control.

6.11 Overtemp Controller PM3 Limit, with TC input.

7. Vacuum Performance

7.1 The roughing system shall be dry oil-free vacuum pump.

7.2 The roughing pump shall be fitted with a stainless steel flexible vacuum hose to reduce the amount of vibration transmitted to the vacuum chamber.

7.3 The roughing pump shall have an inlet isolation valve to allow throttling for slow pump-down. (“slow” pump down is defined in the next bullet point)

7.4 Shall have a soft pump roughing system for slow pump-down (approximately 10 to <1 Torr/Min) from atmosphere to 1 torr to minimize regolith turbulence in chamber that occurs during pump down in that range.

Rationale: There is still a lot of learning to be done as to what a “slow” pump down range means but being able to throttle in the 10 to 0.9 Torr/min range has shown good results thus far.

7.5 The system shall use a non-contaminating style pumping system such as a turbomolecular UHV pump for high vacuum operations.

7.6 The system shall use 2 micron HEPA filtration to protect high vacuum pumps from Lunar Dust/Regolith used inside the chamber during test operations.

7.6.1 Filters shall be easily accessible and replaceable. Filter size needs will change based on the type of test and the type/amount of simulant used.

Planned filter sizes to be used are 0.3 micron and 2 micron.

7.7 A vacuum isolation valve shall be provided between the turbo pump and the chamber.

7.8 The turbopump may be backed by the roughing pump.

7.9 The turbopump foreline shall include a valve with a KF-40 port for leak testing.

7.10 The ultimate vacuum of the system shall be less than or equal to 1.0 x 10-6 Torr.

7.10.1 Pump down times can change based on test article and filtration used, however, baseline pump-down to ultimate vacuum in an empty chamber without filtration shall be achieved in less than 3 hours.

7.11 The system shall have a backfill system capable of using GN2.

7.12 The backfill system shall have a bellows-seal repress metering valve.

7.13 Helium Leak Test:

7.13.1 The chamber vessel shall be Helium mass-spectrometer leak tested for vacuum-tightness in accordance with ASTM E498.

7.13.2 The chamber vessel weld joints shall be leak tested by bagging individual joints or the complete assembly and replacing the air in the bag with Helium via positive pressure purge.

7.13.3 The test shall be accomplished with internal thermal systems (thermal shroud, baseplate) pressurized to MOP with 100% Helium.

7.13.4 Acceptance requires no detectable leak on the most sensitive scale of a Helium leak detector with a minimum criteria of 1X10^-9 mbar-l/sec.

7.14 The system shall have one high vacuum rated safety overpressure relief port.

7.14.1 The port shall be a one-time burst disc style sized 1” minimum to safely relieve over pressure conditions up to 3 psig max caused by the customer test product inside the vessel.

7.14.2 The burst disc shall be replaceable, and the vendor shall supply one extra burst disc with the system.

7.14.3 The system chamber shall be capable of venting at least 6 liters of gas per 3 seconds without over pressurizing.

7.14.4 This port shall be able to be vented to the outside of the test facility.

8. Power

8.1 The NASA facility is equipped with 208VAC, 3-phase 60 amp fusible disconnect.

The system shall utilize this power option.

8.2 The thermal system shall be capable of handling at least 500W of live load.

9. Solar Simulation

9.1 Shall be prepped for future install of solar simulation package to be located at the top of the chamber.

9.1.1 Chamber port with blank for future install of 20" dia window at the top of the chamber.

9.1.2 Thermal shroud port in-line with chamber port, with removable blank panel assembly.

9.1.3 Shall be able to accommodate solar simulation package from Abbess, P/N SolarSim-1600W-12X12-N, or equivalent.

10. Chamber Control System Requirements

10.1 Programmable Logic Controller

10.1.1 Optional: PLC shall be capable of outputting display to an external monitor

Rationale: Want to be able to run output feed to a control room

10.2 HMI Screens

10.2.1 Chamber instrumentation displayed

10.2.2 User settable alarms

11. Safety/Redundancy

11.1 The system shall have emergency shutdown capability in the form of an E-stop switch

11.2 The system shall have loss of power shutdown protection (shuts down in a way that does not present a safety concern or create unnecessary wear or damage to equipment due to improper shutdown sequence)

11.3 The system shall have auxiliary relay shutdown (ambient) input and auxiliary shutdown (ambient) relay output.

12. Administrative

12.1 The system shall have a lead-time of less than or equal to 5 months.

12.2 Accompanying documentation delivered shall include (but not limited to) operational procedures (including startup, operation, shutdown, and emergency operations), cleaning and maintenance overview/plan, MSDSs (if applicable) and calibration sheets.

12.3 Training and installation support shall be included in the total price. There shall be a minimum of two days of training. Installation shall include all required systems.

12.4 NASA shall provide rigging services to have all hardware in place prior to installation.

12.5 Vendor shall provide all necessary hardware for connections to facility power, LN2, GN2, and water connections as described in interface drawings. All connections between vendor supplied chiller (if needed) and Thermal Vacuum system shall be provided and installed by vendor).

12.6 Demonstration of automated run shall be conducted before conclusion of installation.

12.7 In addition to the test chamber, the following shall be provided:

12.7.1 Electrical drawings.

12.7.2 Refrigeration schematic.

12.7.3 Vacuum schematic

12.7.4 Major component vendor literature.

12.7.5 General arrangement drawing or descriptive literature.

12.7.6 Calibration instruction.

12.7.7 Operating instruction and calibration sheets for the as-installed instrumentation, at the time of installation.

12.7.8 Final operation and design limits of the system

12.8 Fabrication drawings shall be reviewed and approved by NASA before final fabrication of system.

12.9 The equipment shall have a 1-year warranty on parts and labor.

12.10 Shipping shall be included in the total price.

12.11 NASA shall manage any industrial solid or hazardous waste generated onsite.

13. Contractor Tasks and Deliverables - The Contractor shall perform the following tasks:

13.1 Milestone 1:

Provide written response of contract receipt detailing requirement satisfaction plan and details necessary for site installation of provided equipment including estimated weight and dimension of associated equipment; gaseous and/or liquid supply and vent diameter, approximate location, and flow rate; notional location of serviceable ports and vacuum pumping equipment; and, electrical power and command, control, and instrumentation interface definition. This information is required and shall be provided in order to prepare the receiving facility for equipment installation and functional verification.

13.2 Milestone 2:

Deliver a final design package including: an updated requirement satisfaction description; changes to the facility modification requirements provided in

Milestone 1 if any; customer-approved equipment drawings and schematics including location of pressure relief and e-stop components; chamber and base plate manufacturing and verification status report; user training plan; and, a delivery schedule including dates for on-site (pre-ship) final verification, product shipment, and implementation of a proposed installation and user training plan.

Changes to the final design package will be negotiated prior to package delivery.

Additional items not defined above can be included in the final design package as necessary to ensure NASA JSC review of equipment features which effect installation within the receiving facility, require operator access, or pertain to safe and successful equipment operation and/or maintenance.

13.3 Milestone 3:

Deliver system and accompanying documentation to the address below and complete installation and training. If facility access or preparedness limitations prevent implementation of the proposed training plan provided in Milestone 2 beyond 90 days from final delivery, this milestone shall be renegotiated to allow partial fulfillment prior to training completion.

14. Period of Performance: 7.5 Months

14.1 Required items shall be delivered according to the following schedule unless reviewed and approved by contract modification.

14.1.1 Milestone 1 shall be delivered within 2 weeks of contract award

14.1.2 Milestone 2 shall be delivered within 8 weeks of contract award

14.1.3 Milestone 3 shall be delivered within 5 months of contract award