N.K. Engineering Co. Offers Linear Vial Washing Machine. N.K. Engineering Co. Is the manufacturer and exporter of machinery for the pharmaceutical industry. Linear Vial Washing Machine consists of special pockets which ensures easy and trouble free washing of vials from outer and inner side. Indexing motion makes easier for syringes to move inside the washing machine, when it is in stationery motion. No Change parts are required from 5 ML to 30 ML of this washing machine. It is user friendly and the semi skilled operator can operate the machine very easily. It consists of infeed conveyor belt system.