two male structural experts inspect large drainage pipes while carrying a toolbox and a blueprint before sending it to pre-construction for the next process. - 硬管 個照片及圖片檔建築地盤, 建築業, 排水
asian colleague engineer working with pipeline and equipment at industrial plant - 硬管 個照片及圖片檔氣體, 工業, 建築業
industrial refinery complex with intricate metal pipes and structures in pittsburgh pennsylvania - 硬管 個照片及圖片檔天然氣, 汽油, 工廠
technician measuring pipe diameter with vernier caliper in industrial workshop - 硬管 個照片及圖片檔焊接, 焊接工人, 不銹鋼