Hollow laum cov khoom tseem hu ua core laum cov khoom, qhov qhib qhov, qhov chaw xyaum, cov phaj steel laum khoom, sib nqus laum khoom, rail laum khoom, thiab lwm yam.
Cov ntaub ntawv tseem ceeb ntawm cov khoom siv laum yog: high-speed steel;hmoov metallurgy;cemented carbide.
Lub hollow laum khoom muaj ntau hom thiab cov lus qhia tshwj xeeb thiab tsim nyog rau ntau lub npe ntawm cov khoom siv sib nqus sib nqus (drills) thiab cov tshuab drilling, milling tshuab, tho txawv tshuab, thiab lwm yam. laum, thiab qhov drilling efficiency yog 8 mus rau 10 npaug ntawm cov khoom xyaum zoo tib yam.