Hng dn thc hnh cc bi tpV K Thut 1 Dng Th Bch Huyn B mn HH_VKT HBK TpHCM BI TP 1: NG NT bi: Thc hin mt bn v k thut vi cc yu cu sau: 1.Chp li cc hnh v theo ng mu quy nh; 2. Bn v c thc hin ng tiu chun Vit Nam (TCVN). Hng dn thc hnh cc bi tpV K Thut 2 Dng Th Bch Huyn B mn HH_VKT HBK TpHCM CC BC THC HIN: 1.Chun b vt liu v dng c v: a.Giy v A4 b.Bt ch c.Ty d.-ke e.Com-pa f.Thc trn 0.3mm0.7mm30cmHng dn thc hnh cc bi tpV K Thut 3 Dng Th Bch Huyn B mn HH_VKT HBK TpHCM g.Ming che ty h.Vn v i.Khn lau 2.Chun b giy v a.o li giy v m bo kch thc t giy ng kh A4 (210x297) b.Lau sch vn v c.C nh giy v vo vn v3.V khung vng v (khung m, b rng nt v 0.7mm) Yu cu: Thc hin ng vi TCVN 7285: 2003. TheotiuchunTCVN7285:2003,khungvngvcvcchcnhtricagiyv 20mm (l tri rng 20mm), cc l cn li rng 10mm.Vy, snh vin cn v sao cho cc cnh ca khung song song vi cnh giy v m bo b rng ca cc l ng vi TCVN. t c yu cu ny, sinh vin cn s dng b -ke vi thao tc trt thc nh sau: (lu:vict-kevtrttmcchvnhngngsongsongnhaurtlinh ng, hnh minh ha di y ch l mt gi ) Hng dn thc hnh cc bi tpV K Thut 4 Dng Th Bch Huyn B mn HH_VKT HBK TpHCM v cc cnh ngang ca khung vng v, ta c nh -ke bn tri, ri trt -ke bn phi xung n v tr cn v, dng ch v m ng xc nh v tr ca nt v. Trtthctheophngng v cc ng nm ngang Hng dn thc hnh cc bi tpV K Thut 5 Dng Th Bch Huyn B mn HH_VKT HBK TpHCM Thc hin tng t cho cc cnh thng ng ca khung bn v. (Lu : trong qu trnh trt thc, hai cnh tip gip nhau ca hai -ke phi lun p st vo nhau m bo tnh chnh xc ca nt v)4.V khung tn Yu cu: Thc hin ng vi TCVN 7285: 2003 TheoTCVN7285:2003,vtrkhungtnctgcdibnphicavngv, hnh thc v ni dung ca khung tn l do c quan thit k quy nh. v khung tn t yu cu, sinh vin cn thc hin thao tc trt thc tng t nh khi v khung vng v. Ch v ng vi kch thc quy nh ca khung tn. tin cho vic o kch thc, ch t thc bn tri sao cho cnh thc c vch chia di (mm) tip xc vi -ke th hai (thc bn phi). Nu t thc nh hnh minh ha di y, ta c th trt -ke bn phi ln v ln lt v c cc cnh ngang ca khung tn. Hng dn thc hnh cc bi tpV K Thut 6 Dng Th Bch Huyn B mn HH_VKT HBK TpHCM Sau khi v c cc cnh ngang, ta o v tr ca -ke bn tri ln pha trn sao cho cnh thc tip xc vi cnh trn ca -ke th hai (xem hinh minh ha di), ri trt thc theo phng ngang v cc cnh thng ng ca khung tn: Khi trt thc, sinh vin cn lun ch sao cho on tip xc gia hai -ke di, m bo cc nt v l song song nhau, khng b lch. Trt thc theo phng ngang v cc ng thng ng Hng dn thc hnh cc bi tpV K Thut 7 Dng Th Bch Huyn B mn HH_VKT HBK TpHCM 5.Vit ch trong khung tn Yu cu: Thc hin ng vi TCVN 7284-0: 2003, 7284-2 : 2003 Khi thc hin bn v tay, yu cu ch vit cn ng kiu ch, chiu cao ch v b rng ch trong mt dng ch cn phi u nhau. t c yu cu , cn k dng dn (nt kthtnht,nnkbngukimcacom-pa)vikhongcchccngkcth chn nh sau: vit ng kiu ch, sinh vin cn quan st cc mu ch theo tiu chun: Nu mun s dng thc k ch, cn s dng loi thc ng kiu ch v cn c 2 cy thc: thc c c ch 3.5mm v thc c c ch 5mm. 6. nt 0.7mm cho khung bn v v khung tn Yu cu: Thc hin ng vi TCVN 8-20: 2002 Hng dn thc hnh cc bi tpV K Thut 8 Dng Th Bch Huyn B mn HH_VKT HBK TpHCM Cc nt lin m ca khung bn v v khung tn c b rng nt l 0.7mm. Khi v tay, b rngntvcthkhngchnhxc,nhngccntcngloiphithngnhtvinhau trn ton bn v. Nt lin m cn t c cc yu t: en m, u, sc nt. nt v t yu cu, cn ch cch cm bt v: Khi nt, cn c gng gi bt thng gc vi mt giy v gi lc ca bt c u t u nt n cui nt. Ch trong khung tn c 2 nt lin mnh (s dng ch 0.3mm v). 7.Thc hin v cc nt lin m, nt t mnh v nt gch di chm mnh Yu cu: Thc hin ng vi TCVN 8-20: 2002 v ng vi kch thc quy nh ca bi Cc kch thc quy nh ca bi nh sau: Hng dn thc hnh cc bi tpV K Thut 9 Dng Th Bch Huyn B mn HH_VKT HBK TpHCM Do hnh v trong bi c b tr gn trong mt khung hnh ch nht, nn trc tin, sinh vin cn v 2 nt dc, song song vi cnh tri v phi ca khung vng v, cch khung vng v 15mm. Cc nt ny cn v tht nht (nn v bng u kim ca com-pa) Hng dn thc hnh cc bi tpV K Thut 10 Dng Th Bch Huyn B mn HH_VKT HBK TpHCM Theo kch thc bi cho, ln lt v nt lin m (ch 0.7mm), ri n nt t mnh (ch 0.3mm). nt t ng vi tiu chun, ch v chiu di 1 gch v khong h gia 2 gch theo s liu thc hnh nh sau: Tng t, nt gch di chm mnh c v vi chiu di 1 gch v khong h gia 2 gch l: 8.Thc hin v khi tr trn xoay trc nm ngang v s dn mi: Yu cu: Thc hin ng vi TCVN 8-20: 2002 (tiu chun v ng nt), TCVN 7583-1 : 2006 (tiu chun v ghi kch thc) v ng vi kch thc quy nh ca bi Hng dn thc hnh cc bi tpV K Thut 11 Dng Th Bch Huyn B mn HH_VKT HBK TpHCM Kch thc quy nh: Kch thc 500 l chiu di thc t ca tr. Do trn hnh biu din s dng nt dch dc gii hn phn c biu din (ch biu din 2 u tr, khng biu din on gia), nn trn hnh v, on thng biu din kch thc 500 c chiu di ty thuc vo phn giy v. Nt gch di chm mnh biu din ng trc ca tr cn v vt qu ng bao ngoi ca hnh biu din 2-3mm. Nt dch dc cn v vt qu ng bao ngoi ca hnh biu din 1.5mm. Khi ghi kch thc, cn lu : ng kch thc gn hnh biu din nht cch ng bao ti thiu l 10mm. ng dng vt qu mi tn 2mm. S dng mi tn 30o t kn. Chiu di mi tn bng vi kh ch ca gi tr kch thc (2.5 3.5 mm) Quy nh v v tr ca gi tr kch thc: S dn mi nu c v y : Hng dn thc hnh cc bi tpV K Thut 12 Dng Th Bch Huyn B mn HH_VKT HBK TpHCM Trng hp giy v c gii hn, c th ch v mt na hay hn mt na. Ch cch ghi kch thc theo dc: Cch v k hiu i xng: Hng dn thc hnh cc bi tpV K Thut 13 Dng Th Bch Huyn B mn HH_VKT HBK TpHCM 9.Thc hin v hnh vung v cc cung trn: Yu cu: Thc hin ng vi TCVN 8-20: 2002 (tiu chun v ng nt), TCVN 7583-1 : 2006 (tiu chun v ghi kch thc) v ng vi kch thc quy nh ca bi Kch thc quy nh: dng hnh vung, c th s dng -ke v trt thc theo cnh huyn c th v ng thi cc ng song song v vung gc vi mt ng thng c trc. Gi s v c cnh thng ng bn tri ca hnh vung, ta c th t -ke nh sau: Hng dn thc hnh cc bi tpV K Thut 14 Dng Th Bch Huyn B mn HH_VKT HBK TpHCM Trt -ke bn tri dc theo cnh huyn ca -ke bn phi, ta c th s dng 2 cnh gc vung ca -ke bn tri v cc cnh nm ngang (vung gc vi cnh thng ng bn tri ca hnh vung) v cnh thng ng (song song vi cnh thng ng bn tri ca hnh vung) Thc hin tng t, trt thc theo cnh huyn s d dng v c cc nt nghing bn trong: Hng dn thc hnh cc bi tpV K Thut 15 Dng Th Bch Huyn B mn HH_VKT HBK TpHCM V tr ca hnh v bn phi c th c xc nh da theo kch thc bi: Trnh t dng hnh: Hng dn thc hnh cc bi tpV K Thut 16 Dng Th Bch Huyn B mn HH_VKT HBK TpHCM Dng cc ng tm Dng cc on thng song song vi ng tm (v m) Cc cung trong R16 v R36 xc nh c tm v bn knh. m cc cung trn m cc on thng sao cho tip xc vi cung trn Ghi kch thc Ch b tr kch thc sao cho cc ng kch thc cng nm trn mt ng thng: