N252-074 TITLE: Materials Optimization for 81mm M299 Ignition Cartridge System
OUSD (R&E) CRITICAL TECHNOLOGY AREA(S): Advanced Materials;Sustainment
The technology within this topic is restricted under the International Traffic in Arms Regulation (ITAR), 22 CFR Parts 120-130, which controls the export and import of defense-related material and services, including export of sensitive technical data, or the Export Administration Regulation (EAR), 15 CFR Parts 730-774, which controls dual use items. Offerors must disclose any proposed use of foreign nationals (FNs), their country(ies) of origin, the type of visa or work permit possessed, and the statement of work (SOW) tasks intended for accomplishment by the FN(s) in accordance with the Announcement. Offerors are advised foreign nationals proposed to perform on this topic may be restricted due to the technical data under US Export Control Laws.
OBJECTIVE: Develop a suitable material that meets the M299 Ignition Cartridge (IC) Tube Assembly Technical Data Package (TDP) requirements and an engineering solution to optimize the current design while aligning with historical pressure characteristics and current range precision requirements.
DESCRIPTION: The current M299 IC system consists of the following critical components:
a. Flash Tube Assembly
b. Tube Assembly
c. Firing Plug
d. Head
e. Black Powder Pellet
f. Primer 150D
g. Body (drawing 9293428)
h. Cap (drawing 9294756)
The Tube Assembly contains the Tube as the base structure and the Heat Shrinkable Tubing that is applied to the exterior. The current Tube material is a sulfate paper produced using the Kraft wood pulping process and coated with paraffin wax. The current configuration of the Tube is spiral wound such that each layer of the Cartridge Paper is secured with adhesive. The Tube Assembly is positioned over the Flash Tube Assembly, secured to the IC body with adhesive, loaded with M9 flake propellant, and sealed with the Cap and applied adhesive.
The current Tube dimensions are 4.770 +/- 0.015 inches in length, an inner diameter of 0.562 +0.005/-0.000 inches, and a thickness of 0.041 +0.000/-0.010 inches. These dimensions are required to ensure there is proper spacing within the ignition cartridge to provide a cavity for the propellant.
The M299 IC specification (MIL-DTL-32247) allows for a wide range in Tube bursting strength. MIL-DTL-32247 paragraph 3.11 defines the bursting strength requirement as the following:
However, the Army is currently analyzing historical test data to optimize pressure characteristics and tighten the bursting strength requirement. Variation in the Tube wall thickness directly affects bursting strength and therefore the pressure characteristics during the IC deflagration event. IC paper tube materials, design, and manufacturing control processes are critical to maintaining quality and reliability."
Currently, the Tube Assembly dimensional requirements allow for variation in the quantity of Cartridge Paper layers and subsequently affects the bursting strength, causing variability in pressure output. The thickness of the Sulfate Paper is a critical dimension as functional data appears to show a thicker paper and fewer layers causes increased variability in the bursting strength. Adhering to the historical TDP dimensional requirements is considered a significant factor in aligning with historical pressure characteristics and maintaining range precision requirements.
The purpose of this SBIR topic is to prototype an engineering change to the M299 IC system to optimize the form, fit, and function of the Tube Assembly, minimize variability in the bursting strength, and align with historical range precision performance.
The solution does not need to be made from paper. Alternative materials may be considered.
Current Paper Requirements:
1. Paper Properties:
a. Standard Commercial Grade Paraffined Cartridge Paper
b. Color: Yellow No. 33538 of FED-STD-595
c. Basis Weight (gsm): 104 – 117 (Grams per Square Meter)
d. Grade: P03-05
e. Thickness (inch): .0047 to .0053; thickness of one spiral wrap of material
f. Tensile Strength: 75 lbs minimum along the grain; 20 lbs minimum across grain
g. Stretchability: 2.0% minimum along grain; 9.0% minimum across grain
h. Weight: 70 lbs per 500 24" x 36" sheets
i. Bursting Strength (psi): 70+
2. Bursting Strength:
MIL-DTL-32247 paragraph 4.58 defines the Bursting Strength Verification as the following:
a. "The tube shall be cut in half lengthwise and one of the halves placed in the fixture. The stop shall be completely removed or backed off so that it does not touch the punch. Place fixture in universal tester set for a travel speed of 0.125 inches per minute. Proceed with Test Number 1 and 2."
i. TEST NUMBER 1: NO BURST
1. Apply 57-pound compression load, remove tube. Item is rejected if evidence of bursting is observed. Tearing or puncturing of material shall be considered evidence of bursting.
ii. TEST NUMBER 2: BURSTING
1. If item is not rejected, replace it in fixture, using opposite end of tube and apply 192 pounds compression load. If item shows no evidence of bursting (punch travels through material), it shall be rejected.
3. Costs
The Flash Tube Assembly, of which the tube is a component, is estimated to cost $18. The redesigned tube should not increase the cost by more than 10%.
PHASE I: Develop concepts for the paper tube technology that meet the requirements described above. Demonstrate the feasibility of the concepts in meeting Marine Corps requirements by material testing and analytical modeling, as appropriate. Establish that the concepts can be developed into a useful product for the Marine Corps. Provide a Phase II development plan with performance goals and key technical milestones, and that will address technical risk reduction.
PHASE II: Develop a prototype Tube to be assembled to the Tube Assembly for evaluation to determine its capability in meeting the performance goals defined in the Description. Demonstrate technology performance through prototype evaluation and modeling over the required range of parameters. Use evaluation results to refine the prototype into an initial design that will meet Marine Corps requirements; and for evaluation to determine its effectiveness in an operationally relevant environment approved by the Government. Provide thirty (30) complete Tube assemblies that will be used in a live fire mortar testing event. Prepare a TDP for submittal to the Joint Safety Review Board. Provide test support during the live fire testing. Prepare a Phase III development plan to transition the technology into Marine Corps use.
PHASE III DUAL USE APPLICATIONS: Support the Marine Corps in transitioning the technology for Marine Corps use. Support the Marine Corps for test and validation to certify and qualify the system for Marine Corps use.
REFERENCES:
KEYWORDS: Ignition; Cartridge; Paper; Tube; Burst; Mortar
TPOC 1: Benjamin Narez
[email protected]TPOC 2: Matthew Bolen
[email protected]
** TOPIC NOTICE ** |
The Navy Topic above is an "unofficial" copy from the Navy Topics in the DoD 25.2 SBIR BAA. Please see the official DoD Topic website at www.dodsbirsttr.mil/submissions/solicitation-documents/active-solicitations for any updates. The DoD issued its Navy 25.2 SBIR Topics pre-release on April 2, 2025 which opens to receive proposals on April 23, 2025, and closes May 21, 2025 (12:00pm ET). Direct Contact with Topic Authors: During the pre-release period (April 2, 2025, through April 22, 2025) proposing firms have an opportunity to directly contact the Technical Point of Contact (TPOC) to ask technical questions about the specific BAA topic. The TPOC contact information is listed in each topic description. Once DoD begins accepting proposals on April 23, 2025 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. DoD On-line Q&A System: After the pre-release period, until May 7, 2025, at 12:00 PM ET, proposers may submit written questions through the DoD On-line Topic Q&A at https://www.dodsbirsttr.mil/submissions/login/ by logging in and following instructions. In the Topic Q&A system, the questioner and respondent remain anonymous but all questions and answers are posted for general viewing. DoD Topics Search Tool: 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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