20101-2010 งานนิวเมติกส์และไฮดรอลิกส์เบื้องต้น

Art_ok.indd 201 7/5/2562 10:33:15

Art_ok.indd 202 7/5/2562 10:33:16

Art_ok.indd 203 7/5/2562 10:33:16

Art_ok.indd 204 7/5/2562 10:33:16

Art_ok.indd 205 7/5/2562 10:33:16

Art_ok.indd 206 7/5/2562 10:33:17

Art_ok.indd 207 7/5/2562 10:33:17

Art_ok.indd 208 7/5/2562 10:33:17

Art_ok.indd 209 7/5/2562 10:33:17

Art_ok.indd 210 7/5/2562 10:33:17

Art_ok.indd 211 7/5/2562 10:33:17

Art_ok.indd 212 7/5/2562 10:33:18

Art_ok.indd 213 7/5/2562 10:33:18

Art_ok.indd 214 7/5/2562 10:33:18

Art_ok.indd 215 7/5/2562 10:33:18

Art_ok.indd 216 7/5/2562 10:33:18

Art_ok.indd 217 7/5/2562 10:33:19

Art_ok.indd 218 7/5/2562 10:33:19

Art_ok.indd 219 7/5/2562 10:33:19

Art_ok.indd 220 7/5/2562 10:33:19

Art_ok.indd 221 7/5/2562 10:33:19

Art_ok.indd 222 7/5/2562 10:33:20

Art_ok.indd 223 7/5/2562 10:33:20

Art_ok.indd 224 7/5/2562 10:33:20

17 ≈‘Èπ°—π°≈—∫·∫∫§«∫§ÿ¡‰¡‰à ¥·â ≈–§«∫§¡ÿ ‰¥â  “√–°“√‡√¬’ π√Ÿâ 17.1  “√– ”§≠— ª√–®”Àπ«à ¬ 17.2 ≈È‘π°—π°≈—∫·∫∫§«∫§¡ÿ ‰¡à‰¥â 17.3 ≈π‘È °—π°≈—∫·∫∫§«∫§¡ÿ ¥â«¬π”È ¡—π‰Œ¥√Õ≈°‘ 17.4 „∫ß“πÀπ«à ¬∑Ë’ 17 º≈°“√‡√¬’ π√ŸÑ∑˧’ “¥À«ß— 1. Õ∏‘∫“¬ “√– ”§—≠ª√–®”Àπ૬‰¥â 2. Õ∏‘∫“¬≈π‘È °—π°≈—∫·∫∫§«∫§ÿ¡‰¡‰à ¥‰â ¥â 3. Õ∏∫‘ “¬≈Èπ‘ °π— °≈∫— ·∫∫§«∫§ÿ¡¥â«¬π”È ¡—π‰Œ¥√Õ≈°‘ ‰¥â 4. ∑¥≈Õß„™âß“πÀπ«à ¬∑Ë’ 17 ‰¥â 5. ‡æË◊Õ„Àâ¡’°‘®π‘ —¬„π°“√∑”ß“π¥â«¬§«“¡ª√–≥’µ ‡√’¬∫√âÕ¬ ¢¬—π Õ¥∑π Art_ok.indd 225 7/5/2562 10:33:20

218 ß“ππ‘«·¡µ‘° å·≈–‰Œ¥√Õ≈‘° å‡∫◊ÈÕßµâπ 17 ≈Èπ‘ °—π°≈∫— ·∫∫§«∫§ÿ¡‰¡à‰¥â ·≈–§«∫§¡ÿ ‰¥â 17.1  “√– ”§—≠ª√–®”Àπ«à ¬ ≈‘Èπ°—π°≈—∫∑’Ë„™â„π√–∫∫‰Œ¥√Õ≈‘°¡’Àπâ“∑Ë’§«∫§ÿ¡„Àâπ”È ¡—π‰Œ¥√Õ≈‘°‰À≈‰¥â∑“߇¥’¬« ·≈– ªî¥°—Èπ∑‘»∑“ß°“√‰À≈¬âÕπ°≈—∫ ≈‘Èπ°—π°≈—∫¡’„™â„π∫“ß«ß®√√–∫∫‰Œ¥√Õ≈‘°∑Ë’µâÕß°“√„Àâπ”È ¡—π ‰Œ¥√Õ≈‘°‰À≈‰¥â∑“߇¥’¬«·≈–ªî¥°È—π∑‘»∑“ß°“√‰À≈¬âÕπ°≈—∫ πÕ°®“°π’Ȭ—ß„™âªÑÕß°—𧫓¡¥—π Ÿß Ê µË” Ê ¿“¬„π√–∫∫¬âÕπ°≈—∫‡¢â“ Ÿàªôí¡‰Œ¥√Õ≈‘° ·≈–ªÑÕß°—ππÈ”¡—π‰Œ¥√Õ≈‘°‰À≈°≈—∫∂—߇Õß ‡æ◊ËÕ‰¡à„Àâ ‡°‘¥™Õà ß«à“ßÕ“°“»¢Èπ÷ ¿“¬„π∑àÕπ”È ¡π— ‰Œ¥√Õ≈°‘ °√–∫Õ°‰Œ¥√Õ≈‘° ≈‘Èπ§«∫§¡ÿ Õ—µ√“‰À≈ ≈‘Èπ®”°—¥§«“¡¥—π ≈‘Èπ∑‘»∑“ß ∑àÕ‰À≈°≈—∫ ∑àÕ§«“¡¥—π ≈‘Èπ°—π°≈—∫ ªíö¡ ∑àÕ¥¥Ÿ ∂—ßπÈ”¡—π °√ÕßπÈ”¡—π πÈ”¡—π‰Œ¥√Õ≈‘° √Ÿª∑’Ë 17.1 «ß®√‰Œ¥√Õ≈‘°„™â≈‘Èπ°—π°≈—∫∑’Ë≈‘Èπ§«∫§¡ÿ Õ—µ√“‰À≈°—∫∑àÕ∑“ßπÈ”¡—π‰À≈°≈—∫®“°°√–∫Õ°‰Œ¥√Õ≈‘° ·∫∫∑”ß“π 2 ¥â“π‰À≈°≈—∫∂—ßπÈ”¡—π‰Œ¥√Õ≈‘° Art_ok.indd 226 7/5/2562 10:33:21

ß“ππ‘«·¡µ‘° å·≈–‰Œ¥√Õ≈‘° å‡∫◊ÈÕßµâπ 219 17.2 ≈È‘π°π— °≈—∫·∫∫§«∫§ÿ¡‰¡à‰¥â  —≠≈—°…≥å  —≠≈°— …≥å ·∫∫‰¡à¡’ ª√‘ß ≈È‘π°—π°≈∫— ·∫∫§«∫§ÿ¡‰¡‰à ¥â ‡¢’¬π ‰¥â 2 ·∫∫§Õ◊ ¡ ’ ª√ß‘ ·≈–‰¡¡à  ’ ª√ß‘ (Check Valve or Non-Return Valve) ·∫∫¡’ ª√‘ß °√«¬≈‘Èπ  ª√‘ß≈‘Èπ Àπâ“∑Ë’ Pe ≈‘Èπ°—π°≈—∫¬Õ¡„Àâπ”È ¡—π‰À≈ºà“π ‡√◊Õπ≈‘Èπ ∑“߇¥’¬« ªî¥°—Èπ°“√‰À≈¬âÕπ ®”·π°‡ªìπ ·∫∫≈‘Èπ≈Ÿ°ªóπ·≈–·∫∫≈È‘π°√«¬ √Ÿª∑’Ë 17.2  à«πª√–°Õ∫¢Õß≈‘Èπ À≈°— °“√∑”ß“π 17 ≈È‘ π °— π ° ≈— ∫ · ∫ ∫ § « ∫ §ÿ ¡ ‰ ¡à ‰ ¥â ∑ÿ°·∫∫¡’ à«πª√–°Õ∫·≈–À≈—°°“√∑”ß“π ‡À¡◊Õπ°—π §◊Õ ª√‘ß≈È‘π¥—πµ—«≈È‘π„ÀâπË—ßÕ¬àŸ ∫π∫à“≈È‘π ‰¡à„ÀâπÈ”¡—π‰Œ¥√Õ≈‘°‰À≈ºà“π ®π°«à“§«“¡¥—ππ”È ¡—π‰Œ¥√Õ≈‘°®–‡Õ“™π– ·√ß ª√‘ß≈‘Èπ‰¥â ≈‘Èπ®÷ß®–‡ªî¥„Àâπ”È ¡—π ‰Œ¥√Õ≈‘°‰À≈º“à π °“√„™ßâ “π ‰À≈ºà“π „Àâ‡≈◊Õ°„™â·µà≈–·∫∫µ“¡§«“¡ ‡À¡“– ¡¢Õß«ß®√ ‡™àπ °π— π”È ¡π— ‰Œ¥√Õ≈°‘ ®“°«ß®√‰À≈¬âÕπ°≈—∫ªöí¡‰Œ¥√Õ≈‘° À√◊Õ ‡ªìπ≈πÈ‘ √—°…“§«“¡¥π— πÈ”¡π— ¢≥–‰¡¡à ¿’ “√– √Ÿª∑’Ë 17.3 ≈‘Èπ°—π°≈—∫·∫∫≈Ÿ°ªóπ°≈¡·≈–·∫∫°√«¬ Art_ok.indd 227 7/5/2562 10:33:21

220 ß“ππ‘«·¡µ‘° å·≈–‰Œ¥√Õ≈‘° å‡∫◊ÈÕßµâπ 17.3 ≈πÈ‘ °—π°≈—∫·∫∫§«∫§ÿ¡¥«â ¬πÈ”¡π— ‰Œ¥√Õ≈°‘  —≠≈—°…≥å  —≠≈—°…≥å ≈‘Èπ‡≈◊ËÕπ ≈‘Èπ°—π°≈—∫·∫∫§«∫§ÿ¡¥â«¬π”È ¡—π √Ÿª∑’Ë 17.4 ≈‘Èπ°—π°≈—∫ ‰Œ¥√Õ≈°‘ (Non-Return Valve, Hydraulically Pilot-Operate) À≈°— °“√∑”ß“π¢Õß≈‘πÈ °—π°≈—∫ µ”·Àπà߬ߗ ‰¡∑à ”ß“π πÈ”¡—π‰Œ¥√Õ≈‘° ºà“π‡¢“â √Ÿ P ‰ª√Ÿ A ‰¡‰à ¥â µ”·Àπàß∑”ß“π ¡’πÈ”¡—π§«∫§ÿ¡‡¢â“ √Ÿ Z ¥—π≈È‘π‡≈◊ËÕπ‰ª∑“ߢ«“¡◊Õ„Àâ¡—π L ‰À≈ °≈∫— ∂—ß ·°π≈‘Èπ‡≈Ë◊Õπ‰ª¥—π≈È‘π°—π°≈—∫„Àâ‡ªî¥ πÈ”¡π— ‰Œ¥√Õ≈‘°‰À≈º“à π®“°√Ÿ P ‰ª√Ÿ A ‰¥â ¢âÕ ß— ‡°µ ☞ ∂â“¡’πÈ”¡—π‰Œ¥√Õ≈‘°§«“¡¥—π Ÿß‰À≈ ¬Õâ π°≈—∫ ≈πÈ‘ °—π°≈∫— ®–ª¥î ∑—π∑’ °“√„™ßâ “π  ”À√—∫§«∫§ÿ¡·¡à·√߬°√∂À√◊Õ¬° ß“πÀπ—°„π√–∫∫Õÿµ “À°√√¡ ‚¥¬¬°„Àâ§â“ß À√◊Õª≈àÕ¬≈ß„Àâ§â“ßÕ¬Ÿàµ”·Àπàß„¥ Ê °Á‰¥â µ“¡µÕâ ß°“√ °â“π Ÿ∫‰Œ¥√Õ≈‘°®–∂Õ¬°≈—∫‡Õß ¥«â ¬π”È ¡—π∑¬’Ë °À√Õ◊ πÈ”Àπ°— √∂ √Ÿª∑’Ë 17.5 «ß®√·¡à·√߬°¢ÕßÀπ—° 7/5/2562 10:33:21 Art_ok.indd 228

ß“ππ‘«·¡µ‘° å·≈–‰Œ¥√Õ≈‘° å‡∫◊ÈÕßµâπ 221 „∫ß“πÀπ«à ¬∑Ë’ 17 ≈Èπ‘ °π— °≈∫— ≈”¥—∫∑’Ë 17.1 1. ®ß‡¢’¬π™Õ◊Ë  —≠≈°— …≥å·≈–§”»—æ∑å 1.1 ..................................................................... 1.2 ..................................................................... 2. ®ßµàÕÕÿª°√≥Ωå °ñ ∑¥≈Õßµ“¡«ß®√¢“â ß≈à“ß 17 3. ®ß‡¢¬’ π™Õ◊Ë Õÿª°√≥Ωå °ñ ∑’Ë ”§—≠ 4. ®ß‡¢’¬π≈”¥—∫°“√∑¥≈Õß 1 ............................................. 1. µÈß— §«“¡¥—π™ÿ¥µπâ °”≈ß— ‰«â∑Ë’ .......... 2 ............................................. ............................................... 3 ............................................. 2. ª√—∫≈È‘π√–∫“¬ 2 ‰«â∑’Ë ............... 4 ............................................. 3. ‡≈Ë◊Õπ≈‘πÈ ∑»‘ ∑“ß 3 µ“¡ ............. 5 ............................................. 4. °√Õ°º≈„π ............................... 6 ............................................. 7 ............................................. 8 ............................................. Art_ok.indd 229 7/5/2562 10:33:21

222 ß“ππ‘«·¡µ‘° å·≈–‰Œ¥√Õ≈‘° å‡∫◊ÈÕßµâπ „∫ß“πÀπ૬∑Ë’ 17 ≈‘Èπ°π— °≈—∫ ≈”¥—∫∑’Ë 17.2 5. ®ß∫—π∑°÷ º≈°“√∑¥≈Õß µ”·Àπßà ≈Èπ‘ ≈È‘π‡ª¥î ›ª¥î πÈ”¡—π‰À≈ (‰À≈/‰¡‰à À≈) ≈°Ÿ  ∫Ÿ ∑”ß“π §«“¡¥—π ∑»‘ ∑“ß 3/2 7a 7b 7c T1 T2 T3 (ÕÕ°/°≈—∫/À¬ÿ¥) Pe2 (kPa) a ª¥î ª¥î ‡ª¥î a ª¥î ‡ªî¥ ‡ª¥î b ª¥î ª¥î ª¥î a ª¥î ª¥î ª¥î a ‡ªî¥ ª¥î ªî¥ ¢Õâ  ß— ‡°µ ☞ ∂“â ‡ª¥î ≈‘πÈ 7a ≈°Ÿ  Ÿ∫®– ................................. À≈—ß®“° ∫Ÿ ‡≈◊ËÕπ≈ß·≈â« §«“¡¥π— Pe2 ®–............................................. ☞ °“√‡≈ÕË◊ π≈ߢÕß≈°Ÿ  Ÿ∫∑”„Àâ¡’π”È ¡—π ....................................................................... ☞ „π√–À«“à ß°“√∑¥≈Õß∑È—ßÀ¡¥ ®–‰¡¡à ’πÈ”¡π— ‰À≈ºà“π≈‘Èπ°π— °≈∫— 4c ‰ª¬ß— .................. πÈ”¡π— ®–‰À≈º“à π∑àÕ T2 ‡¡◊ÕË ≈πÈ‘ ∑‘»∑“ß 4/2 Õ¬à„Ÿ π.......................·≈–≈π‘È ‡ªî¥-ª¥î 7b .......................... ☞ ‡¡◊ËÕ≈‘Èπ∑‘»∑“߇≈◊ËÕπÕ¬Ÿà„πµ”·Àπàß b ≈Ÿ° Ÿ∫®–‡≈Ë◊ÕπÕÕ° (§«“¡¥—π Pe2 ‡æ‘Ë¡¢÷Èπ) ≈‘Èπ‡ªî¥-ªî¥ 7a ®–‰¡à¡’º≈µàÕ...........................‡æ√“–πÈ”¡—π‰À≈ºà“π≈‘Èπ°—π°≈—∫‰ª¥—π ≈°Ÿ  ∫Ÿ ‰¥â ≈Ÿ° ∫Ÿ  “¡“√∂À¬ÿ¥‰¥‡â ¡◊ÕË ....................................................................... §«“¡¥π— Pe2 ®–≈¥≈ߥ—ß.................................................................................... 6.  √ÿªº≈°“√∑¥≈Õß ≈‘Èπ°π— °≈—∫®–¢«“ß°È—π°“√‰À≈∑»‘ ∑“ßÀπ÷ßË ·≈–®–ª≈Õà ¬„Àâ¢Õ߉À≈‰À≈º“à π‰¥„â π ........... ..................∑‘»∑“ß°“√‰À≈º“à π≈πÈ‘ °π— °≈∫— πÈ®’ – ß— ‡°µ‰¥®â “° .................................... Art_ok.indd 230 7/5/2562 10:33:21

ß“ππ‘«·¡µ‘° å·≈–‰Œ¥√Õ≈‘° å‡∫◊ÈÕßµâπ 223 ‡√Õ◊Ë ß ≈πÈ‘ °π— °≈∫— ·∫∫§«∫§¡ÿ ‰¡‰à ¥·â ≈–§«∫§¡ÿ ‰¥â °®‘ °√√¡∑Ë’ 17 1. ®ß‡¢¬’ π·∫∫≈πÈ‘ °π— °≈∫— ·∫∫≈È‘π√Ÿª°√«¬ (Cone as Seal) ‡ªπì ¿“æµ—¥‡µÁ¡„π°√Õ∫∑°’Ë ”Àπ¥„Àâ 2. ®ß· ¥ß∑»‘ ∑“ß°“√‰À≈¢ÕßπÈ”¡π— ºà“π≈πÈ‘ °—π°≈—∫ ®“° A ‰ª B ¥â«¬ª“°°“ ’π”È ‡ßπ‘ ®“° B ‰ª A ¥â«¬ª“°°“ ·’ ¥ß 17 3. ≈‘πÈ ∑»‘ ∑“ß„™ â ”À√∫— ß“πÕ–‰√ ................................................................................................................................. ................................................................................................................................. 4. ®ß‡¢¬’ π™ÕË◊  à«πª√–°Õ∫À≈—°¢Õß≈Èπ‘ °—π°≈∫— ¡“ 3 ¢âÕ 1 .......................................................................................................................... 2 .......................................................................................................................... 3 .......................................................................................................................... Art_ok.indd 231 7/5/2562 10:33:22

224 ß“ππ‘«·¡µ‘° å·≈–‰Œ¥√Õ≈‘° å‡∫◊ÈÕßµâπ 5. π”È ¡π— ‰Œ¥√Õ≈°‘ ®–‰À≈º“à π≈π‘È °π— °≈∫— ‰¥â‡¡◊ÕË ‰√ ∂“â ∑ß—È  Õߥ“â π¢Õß≈‘πÈ °—π°≈∫— ¡§’ «“¡¥—π ................................................................................................................................. ................................................................................................................................. 6. ®ß‡¢¬’ πÀπ“â ∑π’Ë È”¡—π‰Œ¥√Õ≈‘°„π√–∫∫‰Œ¥√Õ≈°‘ 6.1 .......................................................................................................................... 6.2 .......................................................................................................................... 6.3 .......................................................................................................................... 6.4 .......................................................................................................................... 7. ≈πÈ‘ √–∫“¬§«“¡¥π— ®–ª¥î °π—È Õ¬‰Ÿà ¥ â ߟ  ¥ÿ ∑’Ë Pe = °’Ë kPa ∂“â ·√ß ª√ß‘ ≈πÈ‘ = 8 kp ¢π“¥√≈Ÿ π‘È √–∫“¬ = 10 mm ................................................................................................................................. ................................................................................................................................. ................................................................................................................................. ................................................................................................................................. ................................................................................................................................. ................................................................................................................................. ................................................................................................................................. ................................................................................................................................. 8. ≈‘πÈ °π— °≈∫— „π√–∫∫‰Œ¥√Õ≈°‘ ¡À’ π“â ∑Õ’Ë –‰√ °. §«∫§¡ÿ „Àâπ”È ¡π— ‰Œ¥√Õ≈‘°‰À≈ºà“π‰¥â∑“߇¥’¬« ¢. §«∫§ÿ¡„Àπâ È”¡—π‰Œ¥√Õ≈‘°‰À≈ºà“π‰¥∑⠓߇¥’¬«·≈–‰¡à„Àâ¬âÕπ°≈∫— §. §«∫§¡ÿ „Àπâ È”¡π— ‰Œ¥√Õ≈‘°‰À≈À√’‰Ë ¥â∑“߇¥¬’ «·≈–‰¡à„Àâ¬Õâ π°≈∫— ß. §«∫§ÿ¡„Àπâ È”¡π— ‰Œ¥√Õ≈°‘ ‰À≈√«¥‡√«Á ‰¥∑⠓߇¥’¬« 9. ≈Èπ‘ °—π°≈∫— ·∫∫§«∫§ÿ¡¥â«¬π”È ¡π— ‰Œ¥√Õ≈‘°¡’„™âß“π„π≈—°…≥–„¥ °.  àß°”≈—ߥ⫬πÈ”¡—π‰Œ¥√Õ≈‘°∑»‘ ∑“߇¥¬’ « ¢.  ßà °”≈ß— ¥«â ¬πÈ”¡π— ‰Œ¥√Õ≈°‘ 2 ∑»‘ ∑“ß §. ¬°„À§â “â ßÀ√Õ◊ ª≈àÕ¬„Àâ§â“ßÕ¬Ÿàµ”·Àπßà „¥ Ê ‰¥â ß. ¬°„Àâ§â“߉¥‚â ¥¬‰¡àÕπ— µ√“¬ Art_ok.indd 232 7/5/2562 10:33:22

Art_ok.indd 233 7/5/2562 10:33:22

Art_ok.indd 234 7/5/2562 10:33:22

Art_ok.indd 235 7/5/2562 10:33:22

Art_ok.indd 236 7/5/2562 10:33:23

Art_ok.indd 237 7/5/2562 10:33:23

Art_ok.indd 238 7/5/2562 10:33:23

Art_ok.indd 239 7/5/2562 10:33:23

Art_ok.indd 240 7/5/2562 10:33:23

Art_ok.indd 241 7/5/2562 10:33:23

Art_ok.indd 242 7/5/2562 10:33:24

Art_ok.indd 243 7/5/2562 10:33:24

Art_ok.indd 244 7/5/2562 10:33:24

Art_ok.indd 245 7/5/2562 10:33:24

Art_ok.indd 246 7/5/2562 10:33:24

Art_ok.indd 247 7/5/2562 10:33:24

Art_ok.indd 248 7/5/2562 10:33:25