COMPOSITES LAB MANUAL

Transcription

1 COMPOSITES LAB MANUAL Version 1 Lab 2: Health concerns and safety procedures The original version of this manual was a one student senior design project written by Katherine White, the Composite lab assistant, during Spring 2016 semester under supervision of who captured almost all pictures in this manual. This current version (version 1) has been modified and amended by during Fall 2016 semester in order to be used by students enrolled in ME436/L course: Mechanics and Design with Composite Materials, as well as Senior Design students. 1

2 1. Health Concerns and Safety Procedures You must participate in the Composites Safety training in order to use the composites lab for manufacturing. One must always use Personal Protective Equipment (PPE) when handling composite materials in a layup operation. Always wear high quality latex or nitrile gloves when handling composites/resins/release products. Wear an organic vapor mask when using liquid release agents and resins. Use a particle mask when cutting or machining composites. Always use a special vacuum with a proper filter when grinding, machining, or cutting through composites to collect all particles which are toxic. Watch for skin sensitivity if fibers or dust get on the skin. Thoroughly clean any exposed skin after using resins and reinforcements. Wearing long sleeves in addition to gloves will help. Safety glasses should be worn when cutting, machining, or grinding the composite. Safety glasses should also be worn when mixing or applying chemicals to ensure it doesn t splash into the eye. Disposable lab coats and pants are used to protect clothing. Do not touch face, skin, etc. while handling resins. If preventive measures are not taken, you could get overexposed to vapors or inhaling of fibers, industrial dermatitis (skin irritation), or severe eye injury. Figure 1: (left) Organic Vapor Mask, (right) Particle Mask Check list: Gloves Supplies that will not react with the resin in an exothermic reaction (paper plates, bowls, nonsynthetic brushes, etc.). Treat all mixing containers as potentially a fire hazard and also as a hazardous waste until it is cured. A safe place to mix resin that will not increase the fire hazard of resin Only perform layup operations in a well-ventilated area and always have any cleanup performed in a well-ventilated area also. Review all technical and material safety data sheets (MSDS) prior to handling materials. MSDS sheets describe all necessary safety data about the material you are handling. Allocate enough space to work safely. Resins are messy and easy to get on other people s clothes, be thoughtful about the workspace. 2

3 Designate a specific area to use release agents which can contaminate the layup. The area you are working in is designated and safe for composite materials Prepare all tools, chemicals, PPE, and your reinforcement material kit prior to mixing any chemicals. (The kit is pre-cut pre-preg or reinforcement fabric that is labeled with the proper layup direction and stacked in the layup order). If you are doing a wet layup make sure to use a timer once you begin mixing resin so that you can predict when the resin will gel and begin curing. Designate specific areas for any grinding, sanding, drilling, sawing or machining of composites. This area should be well ventilated and all personnel should be wearing particle masks and safety glasses. This should not be an area where a layup is occurring because the dust is considered a contaminate to the layup process. Cartridges of Vapor Masks have expiration dates and MUST be replaced. They should be stored in 1 gallon Ziploc bags to ensure they are kept fresh and can protect you. Be careful of the resin/hardener chemical reaction, which is an exothermic reaction, and be sure to place any mixing container only in a nonflammable area. Do not to touch face, skin, etc while handling resins. Explain how to remove epoxy from skin if exposed. Discuss handling and cutting of dry fibers with caution and using the proper PPE because glass or carbon fibers can cause itching or skin irritation. Hazards: Resins, Gel Coats, Acetone, PVA, some Epoxy Hardeners are FLAMMABLE Uncured resin and pre-preg are considered hazardous until cured. Any scraps must be cured before they are thrown away. Before using any major equipment in the lab such as the autoclave or CNC router, you have to: - Complete a specific training for this machine - Use the proper PPE - Inspect the equipment before use, - Clean up immediately after use - Make sure a backup person is present Cleaning Once the part is ready to be cured, it must be moved to a curing oven or simply left to cure in place until the next day. Then a cleanup must be done before leaving the lab. All the materials used (brushes, rollers, mixing tools, scissor), including the table, must be cleaned using acetone and cloth. Also, the rest of the fiberglass woven reinforcement must be collected from the table and floor. How to dispose of acetone: Soap and water can be used on skin if exposed. Some shop hand cleaners work well also. Note: scissors, rollers etc., are particularly susceptible to damage if not cleaned immediately after use with resin. 3

4 The lay up will harden after about an hour, but leave the lay up overnight and then evaluate them sometime after that curing period. Consider the foolowing: (1) All resins and pre-pregs must be fully cured before they are thrown away. (2) Throw away all bagging tape and films, attempts at re-use can ruin a layup. (3) Put all re-usable tools that came in contact with resin (mixing sticks, brushes, roller handles, metal rollers, scissors, etc.) into cups of acetone so that resin doesn t permanently adhere to them. (4) Remove foam roller attachments before resin cures and clean handles with acetone. Figure 2: Use mixing tools that need to be soaked in acetone 4

5 Dealing with Chemicals Release wax: 5

6 Release agents: 6

7 Epoxy Resin: 7

8 Epoxy Hardner: 8

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10 Prepregs: 10

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