N231-043 TITLE: Extreme Cold Weather Resistant Gasket Material
OUSD (R&E) CRITICAL TECHNOLOGY AREA(S): General Warfighting Requirements (GWR)
OBJECTIVE: Develop an advanced, cold weather resistant gasket material capable of being used in a ship�s external gaskets.
DESCRIPTION: The US Navy�s DDG-51 Class destroyers utilize many elastomer seals and gaskets throughout the ship with many exposed to the environment. As the Navy sails increasingly into Polar regions, seals and gaskets are exposed to extreme cold weather leading to performance degradation and premature seal failure resulting in a limited operating environment. Market research has not resulted in a Navy approved material that can survive in the Arctic environment across the spectrum of required seals and gaskets. A new cold weather resistant gasket is needed to replace the existing neoprene gaskets and seals.
The development of a cold weather resistant gasket materials that meet the Navy need will require innovation to overcome technical challenges. The gasket material must meet the mechanical requirements of the Navy to include sustained heavy loads and other forces associated with ship motion, exposure to the harsh maritime environment, saltwater immersion, exposure to industrial chemicals, jet fuel, and fire resistance. Additionally, the gasket material must have excellent performance with minimal loss of mechanical properties at temperatures as low as -50�F while remaining a cost-effective solution for the Navy.
Research into cold weather resistant gaskets has identified several materials that could potentially be developed to meet the Navy�s need. There are materials available which demonstrate the required temperature resistance; however, none of these materials have been demonstrated to meet the Navy�s full set of requirements. Additional innovation is required to produce a viable product for the Navy.
PHASE I: Develop a concept for cold weather resistant gasket materials that meets the requirements described above. Demonstrate the feasibility of the concept in meeting Navy needs and establish that the concept can be developed into a useful product for the Navy. Feasibility will be established by coupon development and laboratory testing and demonstration of the manufacturability of the materials. The Phase I Option, if exercised, will include the initial design specifications and capabilities description to build a prototype solution in Phase II.
PHASE II: Based on the results of Phase I and the Phase II Statement of Work (SOW), develop and deliver prototype louver gaskets for evaluation. The prototypes will be evaluated to determine capability in meeting the performance goals defined in the Phase II SOW. Product performance will be demonstrated through prototype evaluation, modeling, analytical methods, and demonstration over the required range of parameters including numerous cycles of various compressive loads. An extended test in a maritime environment will be used to refine the prototypes into a design that will meet Navy requirements. Prepare a Phase III manufacturing and development plan to transition the innovative new gasket material for Navy use.
PHASE III DUAL USE APPLICATIONS: Support the Navy in transitioning the cold resistant elastomer to Navy use. Develop installation and maintenance manuals for the new gasket material to support transition to the fleet.
Numerous potential private sector uses for cold weather resistant gaskets, with applications in the commercial shipping industries, as well as Arctic construction. Other commercial applications include commercial research and cryogenics.
REFERENCES:
1. Liao, Shenglong. "An Ultra-Low-Temperature Elastomer with Excellent Mechanical Performance and Solvent Resistance." Advanced Materials, September 2021. https://www.researchgate.net/profile/Shenglong-Liao/publication/353433116_An_Ultra-Low-Temperature_Elastomer_with_Excellent_Mechanical_Performance_and_Solvent_Resistance/links/60fe6b382bf3553b291079c9/An-Ultra-Low-Temperature-Elastomer-with-Excellent-Mechanical-Performance-and-Solvent-Resistance.pdf
2. Ashrafizedeh, H. et al. "Evaluation of the Effect of Temperature on Mechanical Properties and Wear Resistance of Polyurethane Elastomers." Department of Mechanical Engineering, University of Alberta, Edmonton, Alberta, Canada, T6G 1H9, 2016. https://www.epfl.ch/labs/tic/wp-content/uploads/2018/10/P3.pdf
KEYWORDS: Cold Resistant Elastomers; Operational Temperature; Arctic Hardening; Gasket material in Polar regions; Polar operations; Environmental exposure
** TOPIC NOTICE ** |
The Navy Topic above is an "unofficial" copy from the Navy Topics in the DoD 23.1 SBIR BAA. Please see the official DoD Topic website at www.defensesbirsttr.mil/SBIR-STTR/Opportunities/#announcements for any updates. The DoD issued its Navy 23.1 SBIR Topics pre-release on January 11, 2023 which opens to receive proposals on February 8, 2023, and closes March 8, 2023 (12:00pm ET). Direct Contact with Topic Authors: During the pre-release period (January 11, 2023 thru February 7, 2023) proposing firms have an opportunity to directly contact the Technical Point of Contact (TPOC) to ask technical questions about the specific BAA topic. Once DoD begins accepting proposals on February 8, 2023 no further direct contact between proposers and topic authors is allowed unless the Topic Author is responding to a question submitted during the Pre-release period. SITIS Q&A System: After the pre-release period, and until February 22, 2023, (at 12:00 PM ET), proposers may submit written questions through SITIS (SBIR/STTR Interactive Topic Information System) at www.dodsbirsttr.mil/topics-app/, login and follow instructions. In SITIS, the questioner and respondent remain anonymous but all questions and answers are posted for general viewing. Topics Search Engine: Visit the DoD Topic Search Tool at www.dodsbirsttr.mil/topics-app/ to find topics by keyword across all DoD Components participating in this BAA.
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| 2/27/23 | Q. | Define/explain heavy load? |
| A. | A load refers to a force or deformation that creates stresses and strains which the gasket must resist and remain operational. A �heavy� load in this context would be application specific, and would drive a mechanical property requirement for typical and maximum load capacity. We are intending to find a multi-purpose gasket, but the best focal point is a louver gasket. Recommend referencing figures within MIL-PRF-15624 where other example numerical requirements stem from, as well as MILSPEC MIL-R-6855. | |
| 2/21/23 | Q. | Mechanical properties and requirements: |
| A. | MIL-PRF-15624 is an example of a baseline used for the selection of the material. Subsequently the initial properties needed are 1500 psi tensile and 400 % elongation, compression set of 30% at room temp as per class 1 materials. We would then want to maintain 70% of these properties at low temperature and after exposure to the fluids in question.
As for fire resistance, typically materials are tested for flame spread and smoke generation. There is no specific requirements to use for this, but the material should be at least as good as a neoprene material for flame spread and smoke generation. Ultimately, the required properties are application specific, and due to the broad nature of potential subjected applicability it is difficult to ascribe specific key numerical mechanical properties and requirements. For this reason it is recommended to focus on individual proof of concept rather than satisfying generic requirements. The best reference is the original solicitation and the MILSPEC MIL-R-6855 as well as MIL-PRF-15624. |
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| 2/21/23 | Q. | What is wrong with existing commercial silicone gasket materials? |
| A. | A. Silicones don't perform well with resistance to jet fuel. Silicones could be considered provided they meet the environmental criteria for an external Navy seal, which they are currently not. Jet fuel and extreme weather are likely to be introduced in an external environment which are considerable risks to current Navy seals.
The existing gasket is made out of MIL-R-6855 neoprene rubber. Neoprene is a common base elastomer that is used in a wide variety of rubber products, both within the Navy and the commercial sphere. As for why the louver gasket in particular was chosen, it is simply a neoprene seal with the MIL-SPEC exposed to outside air. Additionally, the Navy anticipates the need for Artic-hardened Destroyers to patrol far northern waters in the near future. This will push the current gasket material to the point of thermal failure and is anticipated to severely degrade its performance. |
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| 2/21/23 | Q. | Regarding the following text from the solicitation:
"The US Navy's DDG-51 Class destroyers utilize many elastomer seals and gaskets throughout the ship with many exposed to the environment." Does this mean that the replacement material will be used for all the gaskets on the DDG-51 destroyer, or are specific gaskets envisioned? |
| A. | We are intending to find a multi-purpose gasket, but one area that is a known failure is a louver gasket. If the material provided is a robust and cost effective solution to the Navy need it may be considered for use elsewhere on the ship. Due to the large nature of that scope it is difficult to provide a comprehensive list of failed gaskets. Companies can search all neoprene gaskets/seals currently used by the Navy and meet all those requirements (mil-std, mil-prf�).
It is recommended to focus on the scope of the RFP, otherwise the applicant will have to guess as to the relative importance of various metrics for a gasket that could be used anywhere (low temperature flexibility, strength, compression, creep, hardness, toughness, fuel, ozone, uv, abrasion �). There is a big difference between a static gasket between pipe flanges and a dynamic seal on a door. |
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| 2/21/23 | Q. | Regarding the following text from the solicitation:
"Market research has not resulted in a Navy approved material that can survive in the Arctic environment across the spectrum of required seals and gaskets." 1. Is there a list of "Navy approved" gasket materials? 2. Does "spectrum" refer to the spectrum of material properties, spectrum of size/shape, or both? |
| A. | 1) Yes, but Navy approval is based on application. Due to the nature of this SBIR, we are looking for a newly developed and technically sound material to meet a range of needs laid out in the original solicitation. That is, please reference "approval" criteria from the laid out expected operating conditions to include temperature, jet fuel, and other extreme environmental conditions.
2) It refers to the spectrum of material properties. |
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| 2/21/23 | Q. | Regarding the following text from the solicitation:
"Additionally, the gasket material must have excellent performance with minimal loss of mechanical properties at temperatures as low as -50�F while remaining a cost-effective solution for the Navy." What are the cost limitations? Can you provide an example of current pricing? |
| A. | The Navy expects to see a cost evaluation for a selected seal. The Navy is looking for proof of concept, to include pricing justification and cost effective analysis or market competition. | |
| 2/21/23 | Q. | Q. Regarding the following text from the solicitation:
"Feasibility will be established by coupon development and laboratory testing and demonstration of the manufacturability of the materials." Are there defined tests for the gaskets? |
| A. | No. Since the RFP specifies replacement of existing neoprene gaskets/seals, companies could search on all neoprene gaskets/seals currently used by the navy and meet all those requirements (search for mil-std, mil-prf�) and also look at the ASTM for test methods. | |
| 2/21/23 | Q. | Are the 'gaskets' used on doorway hatches or openings that repeatedly open and close? |
| A. | There are gaskets within doorways and hatches. The intent is to develop a product capable of external use, but application could be modified if proven successful. Some are stationary, such as intake louvers. | |
| 2/21/23 | Q. | Are the 'Seals' used for external piping carrying liquids or gases? |
| A. | There are gaskets within external piping. The intent is to develop a product capable of external use, but application could be modified if proven successful. Some are stationary, such as intake louvers. | |
| 2/21/23 | Q. | How large (dimension) are these 'gaskets' or 'seals'? |
| A. | There are gaskets in differing location aboard the ship. The intent is to develop a product capable of external use, but application could be modified if proven successful. Some are stationary, such as intake louvers. | |
| 2/21/23 | Q. | Do you have a full set of requirements in addition to the -50F, solvent resistance, salt water resistance? Specifically looking for things like compression set, density, tensile strength, and tear strength. |
| A. | Due to the broad nature of potential application, it is difficult to attribute specific numerical material testing benchmarks. The best reference is the original solicitation and the MILSPEC MIL-R-6855. | |
| 2/21/23 | Q. | What other materials have you tried? |
| A. | Recommend referencing MILSPEC MIL-R-6855, majority of gaskets/seals that have been utilized are based on this. The Navy has not explored other commercial options at this time. Recommend referencing environmental needs in original solicitation. | |
| 2/21/23 | Q. | Is neoprene the only current gasket material used on board ship? |
| A. | No, there are other base materials used onboard. The Navy will consider other materials that could achieve the same level of external weather performance. | |
| 2/21/23 | Q. | What is the typical failure mode of the neoprene material in cold weather? brittleness, cracking, tearing, chemical/fuel exposure, combination thereof? |
| A. | Typical failure mode of neoprene in cold weather mirrors most rubbers: brittleness, cracking/shattering, and leaking. Additionally, silicones don't perform well with resistance to jet fuel. | |
| 2/21/23 | Q. | In addition to a louvre seal, what other geometries are used? i.e. solid cylinder, hollow boot? |
| A. | The louvre seal was target for ease of testing and implementation, there are many other gaskets geometries deployed onboard. The Navy requires new gasket material that can be fit to many geometries due to the large spectrum of potential applications. | |
| 2/21/23 | Q. | What is the typical compression force or deformation gap when compressed in place? |
| A. | This would depends on the specific application, for the example louver gasket please reference MILSPEC MIL-R-6855 | |
| 2/21/23 | Q. | How is the gasket attached to the door sill i.e. press fit slot, bolted, adhesive etc.? |
| A. | Majority press fit or bolted, the Navy does not use adhesive. | |
| 2/21/23 | Q. | What is the lowest operating temperature these seals will see? You mention -50F, but I imagine these seals could see lower temperatures. |
| A. | The seals must be functional at -50F. Anything exceeding -50F is great as the ultimate goal is to allow systems to operate in arctic conditions. | |
| 2/21/23 | Q. | Can you provide any details on the process for developing a Navy approved material for this particular seal? |
| A. | Building testing and qualifying any component to be installed aboard a vessel needs to follow the Navy qualification process and be approved by NAVSEA Tech Warrant Holder in NAVSEA 05 engineering directorate before it can be assessed for install at the ship program level.
For this application, it is expected for a new component to be built, tested, and validated to meet the requirements herein. Then collaboration with Navy POC's will begin and it will be taken through the rest of the process. At this time, the Navy is looking for proof of concept and a prototype. |
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| 2/21/23 | Q. | Is the seal also meant for hangar doors on the DDG-51 and will it need to survive rubbing against deck coatings? Would a door seal be the most extreme area the seal would need to function in terms of abrasion? |
| A. | This project targets other external seal/gaskets, louver gaskets were a target example for ease of testing and implementation. Other seals and gaskets on the ship are beyond the scope of this project. However, if this project succeeds, the new material may be used to make other seals and gaskets on the ship. With this in mind, the door seal is the most extreme area in terms of abrasion on the ship | |
| 2/21/23 | Q. | Can you elaborate on the test methodology to be used to evaluate the various gasket properties in the Phase I, specifically test protocol for:
a. Salt water immersion exposure (salt conc., duration, temperature) b. Cyclic loading (compressive load levels, cycle times, number of cycles) c. Low temperature exposure (any loads applied during low temperature exposure?) d. Exposure to industrial chemicals (what chemicals, methodology of exposure, duration, temperature) e. Fire resistance |
| A. | Testing for proof of concept is at the company's discretion, full qualification testing is different and will be provided from the Navy Tech Warrant Holder to certify the seal/gasket. There are no specific tests that accomplish the above qualifications, it is recommended the company test to these criteria and provide data/proof that the material can withstand the environmental conditions.
At this time the Navy recommends producing prototypes and testing to the standards herein, then making a recommendation based on the capabilities observed. |
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| 2/21/23 | Q. | Is there a scale and/or size of material samples that you would like to see produced for Phase I? Phase II? |
| A. | At this time the Navy is looking for proof of concept for Phase I. For Phase II the Navy would narrow a targeted seal to determine production size, i.e. louvers. | |
| 2/21/23 | Q. | Why is the Navy not just making the fluoroelastomer material listed in the solicitation references? |
| A. | The Navy has not had the resources to test and qualify these. The Navy will consider any material that could achieve the specified external weather performance standards. | |
| 2/21/23 | Q. | 1. What are key mechanical property requirements for Phase 1 at room temperature, ocean conditions, as well as at cold environments?
2. What are water resistance requirements? |
| A. | 1. Due to the broad nature of potential application, it is difficult to attribute specific numerical mechanical (or otherwise) requirement benchmarks. The best reference is the original solicitation and MILSPEC MIL-R-6855. Specifically regarding Phase 1, the Navy is looking for proof of concept of a functioning seal/gasket. For Phase II, the Navy would narrow a targeted seal to determine further fidelity on mechanical requirements, production size etc. It is recommended at this time that companies focus on the louver and MILSPEC in the solicitation, as well as preventing mechanical property failure at -50F and brackish/salinized water, as the intent is to perform in northern Arctic conditions. Typical failure mode in cold weather mirrors most rubbers: brittleness, cracking/shattering, and leaking.
2. See the above answer. |