Fire extinguisher
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| - | There are many possible ways for the fire extinguisher to fail. Most failures could leave the extinguisher completely inoperable. Below is a list of failures and the ways in which they affect the overall performance of the product. | + | There are many possible ways for the fire extinguisher to fail. Most failures could leave the extinguisher completely inoperable. The biggest issues regard the structural integrity of the aluminum canister or problems with the plastic top triggering mechanism. Most failures would result from misuse or misinstallation of the extinguisher. |
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| + | Below is a list of these failures and the ways in which they affect the overall performance of the product. | ||
Revision as of 22:13, 23 September 2007
Automated fire extinguisher
Parts List
| Part # | Part name | QTY | Weight (g) | Function | Material | Manufacturing Process | Image |
|---|---|---|---|---|---|---|---|
| 01 | Mounting Bracket | 1 | 32 | Clasps canister, attaches to wall | Plastic | Injection Mold | FEMountingBracket |
| 02 | Safety Pin | 1 | 3 | Prevents accidental discharge | Pastic | Injection Mold | FESafetyPin |
| 03 | Canister | 1 | 291.5 | Contains extinguishing agent | Aluminum | Deep Drawn | FECanister |
| 04 | Spring | 1 | 3 | Holds discharge valve closed | Plastic | Injection Mold | FESpring |
| 05 | Hose | 1 | 16 | Channels extinguising agent from bottom of canister | Plastic | Extrusion | FEHose |
| 06 | Valve Pin | 1 | 3 | Blocks flow until displaced | Plastic | Injection Mold | FEValvePin |
| 07 | Top Assembly Gasket | 1 | >.5 | Creates seal between top assembly and canister | Rubber | Injection Mold | 
|
| 08 | Hose-Top Assembly Connector | 1 | 2 | Connects hose to top assembly | Plastic | Injection Mold | 
|
| 09 | Valve Pin Top Gasket | 1 | >.5 | Creates a seal on valve | Rubber | Injection Mold | 
|
| 10 | Valve Pin Bottom Gasket | 1 | >.5 | Created a seal on valve | Rubber | Injection Mold | 
|
| 11 | Diffusing Nozzle | 1 | 2 | Changes diameter of extinguishing agent flow | Plastic | Injection Mold | 
|
| 12 | Extinguising Agent | 1 | 1134 | Extinguishes fire | Sodium Bicarbonate | Chemistry Lab | 
|
| 13 | Top Assembly | 1 | Weight | Provides handle for gripping and discharging, holds pressure gauge, provides discharge path from canister to diffuser nozzle | Plastic | Injection Mold |
|
| 14 | Pressure Gauge | 1 | Weight | Provides user with information about pressure of canister - "Empty" or "Full" | (Assembly - Platic, Brass, Aluminum) | Varies | 
|
FMEA
There are many possible ways for the fire extinguisher to fail. Most failures could leave the extinguisher completely inoperable. The biggest issues regard the structural integrity of the aluminum canister or problems with the plastic top triggering mechanism. Most failures would result from misuse or misinstallation of the extinguisher.
Below is a list of these failures and the ways in which they affect the overall performance of the product.
| 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 | Design Engineers | - | 5 | 5 | 3 | 75 | ||
| Pressure Gauge | May not display proper reading. | Empty extinguisher could read as full. | 10 | Pressure from canister not correctly transmitted to gauge. | 2 | Test gauges by slowly discharging canister | 3 | 50 | Increase space around the pressure gauge in order to ensure that the gauge correctly reads the pressure in the canister | Design Engineers | - | 10 | 2 | 3 | 50 | |
| Safety Pin | Pin breaks and cannot be removed | If the pin cannot be removed, the extinguisher will not discharge | 10 | Pin is thin, may snap if not pulled out straight | 3 | Test strength of pin | 2 | 50 | Make pin thicker. Use stronger plastic. | Pin Manufacturer | - | 10 | 3 | 2 | 50 | |
Top Assembly
| Top handle breaks | Cannot depress pin to trigger the extinguisher | 10 | Extinguisher falls or is hit by an object | 1 | Test durability of top handle | 5 | 50 | Increase thickness of plastic. Use Stronger Plastic | Design Engineers | - | 10 | 1 | 5 | 50 | |
| Bottom Handle breaks | Uncomfortable to hold/use | 3 | Extinguisher falls or is hit by an object | 1 | Test durability of bottom handle | 5 | 15 | Increase thickness of plastic. Use Stronger Plastic | Design Engineers | - | 3 | 1 | 5 | 15
| ||
| Valve Pin | Does not seal properly | Could result in slow loss of pressure from the canister, leaving the extinguisher useless | 10 | Rubber gaskets may not fit on the pin correctly resulting in an ineffective seal | 3 | Test seals performance at large range of pressure | 2 | 60 | Find a better way to secure gasket to pin | Design Engineers | - | 10 | 3 | 2 | 60 |
|
| Canister | Over pressurized | Could result in unexpected rapid decompression, rendering the extinguisher useless and possibly exploding | 10 | Canister is over pressurized | 3 | Test canister to see its maximum pressure | 2 | 60 | Increase safety factor by increasing the maximum pressure rating of the canister | Design Engineers | - | 10 | 3 | 2 | 60 |
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