Fire extinguisher
From DDL Wiki
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| + | Automated fire extinguisher | ||
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| + | ! Item & Function !! Failure Mode !! Effects of Failure !! S !! Causes of Failure !! O !! Design Controls !! D !! RPN !! Recmd Actions !! Responsibility & Deadline !! Actions Taken !! S<sup>*</sup> !! O<sup>*</sup> !! D<sup>*</sup> !! RPN<sup>*</sup> | ||
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| + | | rowspan=2 | Mounting Bracket | ||
| + | | Extinguisher falls off bracket | ||
| + | | Compromises structural integrity of the canister and triggering mechanism. | ||
| + | | 8 || Canister not secured to bracket || 5 || Secure canister to bracket || 5 || 125 || Add strap to make sure canister is secured to bracket || Design Engineers || - || 5 || 5 || 5 || 125 | ||
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| + | | Bracket falls off wall | ||
| + | | Compromises structural integrity of the canister and triggering mechanism | ||
| + | | 5 || Bracket not screwed securely to wall || 5 || Test mounting bracket on different types of walls || 3 || 75 || Treat motor axis to add strength || Motor manufacturer prior to purchase|| - || 5 || 5 || 3 || 75 | ||
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| + | | Main shafts || Mechanical Failures: Thermal. Creep. Corrosion. || Depending on degree of failure, blades may begin to clash or will function at a reduced capacity. Noise. Unstable. || 7 || Heat. Applied load from gear train. Shredding unapproved items || 2 || Feed solid items. Run under extreme conditions || 6 || 84 || Treat rod to increase strength. Increase diameter || Machinist(s) prior to installation || - || 7 || 1 || 6 || 42 | ||
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| + | | Helical gear || Mechanical Failures: Shearing. Thermal. Wearing. Plastic deformation to out of spec || Under complete mechanical failure, gear train will not be connected to the motor. Under partial failure, will have possible slippage which will result in inefficient operation and noise || 7 || Heat from motor. Vibrations. Forces from gear train. || 4 || Drive gear at high rpm and/or under intense working conditions || 3 || 84 || Thicker injection mold to make gear larger. Use stronger plastic. || Injection molder(s) prior to installation || - || 7 || 2 || 3 || 42 || | ||
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| + | | rowspan=2 | Shredding cutoff time-delay | ||
| + | * Turns motor on and keeps motor temporarily turning after paper has passed through to ensure complete shredding | ||
| + | | Electrical failures: Short circuited | ||
| + | | rowspan=2 | Product ceases to function reliably. Shredding no longer possible. | ||
| + | | 8 || Intense heat and/or vibrations loosen connections, resulting in intermittent operation || 4 || Run under extreme working conditions || 3 || 96 || Add solder to strengthen connections. Add dampening to decrease effect of vibrations || Switch manufacturer prior to purchase || - || 8 || 3 || 3 || 72 | ||
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| + | | Mechanical Failures: Creep. Fatigue. Deformation. Shear. | ||
| + | | 8 || Flat metal spring fatigues leading to fracture. Thermal deformation from heat generation. Plastic deformation from shredding unapproved items || 4 || Compress and expand spring repeatedly and under extreme conditions || 3 || 96 || Treat metal to strengthen. Increase thickness of spring. || Switch manufacturer prior to purchase|| - || 8 || 2 || 3 || 48 | ||
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| + | | Helical Blade || Mechanical Failures: Shearing. Fatigue. Thermal. Wearing. || Fracture of blade will result in inefficient, but continued, function. Bending of blade can result in wear against other blades, which can also result in a chain reaction leading to complete failure. || 7 || Bending and shearing can result from shredding unapproved items. Fracture and malfunctions can also result from malfunctions of other components such as the main shaft or gears. || 4 || Shred unapproved items. Work at high rpm. Shred lots of paper and/or credit cards || 5 || 140 || Thicker blades for strength. Smaller opening so unapproved items are harder to fit. || Blade stamping department || - || 7 || 2 || 5 || 70 || | ||
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Revision as of 21:31, 23 September 2007
Automated fire extinguisher
| Item & Function | Failure Mode | Effects of Failure | S | Causes of Failure | O | Design Controls | D | RPN | Recmd Actions | Responsibility & Deadline | Actions Taken | S* | O* | D* | RPN* | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Mounting Bracket | Extinguisher falls off bracket | Compromises structural integrity of the canister and triggering mechanism. | 8 | Canister not secured to bracket | 5 | Secure canister to bracket | 5 | 125 | Add strap to make sure canister is secured to bracket | Design Engineers | - | 5 | 5 | 5 | 125 | |
| Bracket falls off wall | Compromises structural integrity of the canister and triggering mechanism | 5 | Bracket not screwed securely to wall | 5 | Test mounting bracket on different types of walls | 3 | 75 | Treat motor axis to add strength | Motor manufacturer prior to purchase | - | 5 | 5 | 3 | 75 | ||
| Main shafts | Mechanical Failures: Thermal. Creep. Corrosion. | Depending on degree of failure, blades may begin to clash or will function at a reduced capacity. Noise. Unstable. | 7 | Heat. Applied load from gear train. Shredding unapproved items | 2 | Feed solid items. Run under extreme conditions | 6 | 84 | Treat rod to increase strength. Increase diameter | Machinist(s) prior to installation | - | 7 | 1 | 6 | 42 | |
| Helical gear | Mechanical Failures: Shearing. Thermal. Wearing. Plastic deformation to out of spec | Under complete mechanical failure, gear train will not be connected to the motor. Under partial failure, will have possible slippage which will result in inefficient operation and noise | 7 | Heat from motor. Vibrations. Forces from gear train. | 4 | Drive gear at high rpm and/or under intense working conditions | 3 | 84 | Thicker injection mold to make gear larger. Use stronger plastic. | Injection molder(s) prior to installation | - | 7 | 2 | 3 | 42 | |
Shredding cutoff time-delay
| Electrical failures: Short circuited | Product ceases to function reliably. Shredding no longer possible. | 8 | Intense heat and/or vibrations loosen connections, resulting in intermittent operation | 4 | Run under extreme working conditions | 3 | 96 | Add solder to strengthen connections. Add dampening to decrease effect of vibrations | Switch manufacturer prior to purchase | - | 8 | 3 | 3 | 72 | |
| Mechanical Failures: Creep. Fatigue. Deformation. Shear. | 8 | Flat metal spring fatigues leading to fracture. Thermal deformation from heat generation. Plastic deformation from shredding unapproved items | 4 | Compress and expand spring repeatedly and under extreme conditions | 3 | 96 | Treat metal to strengthen. Increase thickness of spring. | Switch manufacturer prior to purchase | - | 8 | 2 | 3 | 48 | |||
| Helical Blade | Mechanical Failures: Shearing. Fatigue. Thermal. Wearing. | Fracture of blade will result in inefficient, but continued, function. Bending of blade can result in wear against other blades, which can also result in a chain reaction leading to complete failure. | 7 | Bending and shearing can result from shredding unapproved items. Fracture and malfunctions can also result from malfunctions of other components such as the main shaft or gears. | 4 | Shred unapproved items. Work at high rpm. Shred lots of paper and/or credit cards | 5 | 140 | Thicker blades for strength. Smaller opening so unapproved items are harder to fit. | Blade stamping department | - | 7 | 2 | 5 | 70 |
