Ship builders interact to enhance productivity
Valuable recommendations for increasing productivity in ship building were made at series of interactive sessions
Upbeat about the steady progress ship builders are making in India, Institution of Naval Architects decided to step on the gas and brought together various players in the field to share their expertise and experience for increasing productivity in ship building. They held a number of short sessions over the past few months for this purpose. In the exchange of ideas that took place there were some exclusive presentations providing very useful tips which could enhance productivity.
The wealth of information that was provided would help small and medium size shipyards to undertake measures - though they may seem almost insignificant – for increasing productivity.
One prominent contributor was Ashok Chowgule, Executive Director of Chowgule Group. He advocated the need to operate within a time frame, quantify work and the use of right tools. “The need to keep in mind evaluation of productivity and the benefits needed for a holistic approach greatly increases throughput and enables higher productivity,” Mr Chowgule stated. “The correct measurement process enables improvement in quality depending on the scale of operation. Measurement of work is important for planning the amount of work and resources. Measurement of work is also important for setting performance criteria.”
“Use of appropriate machinery helps to raise reliability and improve productivity,” he said. “CO2is preferred over manual arc welding as it has the advantage of straight line continuous welding, gives cleaner work area, since there are no stubs left. Besides, there is little slag removal, etc.”
Several advantages can accrue using a tower crane which helps to enhance speed of operation and throughput. It was his experience that by using two Noboruders (and used simultaneously), pipe bending machine, CNC cutting machine which have two cutting heads, two plate bending machine with accessories, stage lifting jacks (which move on the plate is useful as it they can easily be maneuvered on the plate) greatly help to boost production. For painting, the use of a cherry picker helps considerably.
At their Chowgule Shipyard in Goa he asserted that they were able to raise productivity significantly. Where they have been producing three 4,500 tonner vessels annually, with this rationalized system of operation they were able to build four vessels a year.
Some useful tips were offered by Shirai and Pranav Sharma, VPs of Bharati Shipyard Ltd. Endorsing the view of having a strict schedule for production and detailed sequence design, they contended that a block erection schedule of one year was preferred. They said that a detailed assembly sequence should have a schedule of 6 months. So also for shell plate bending, steel pre-nesting and delivery, pipe indent and spool fabrication, pre-outfitting, block blasting and painting should all be maintaining a schedule of six months each. “One should concentrate on having sequence design (work design) as the first step and establish “Kanban System”, they suggested. “Advanced shipyards make micro schedule for 6 months to one year.”
Storage was another aspect which seldom got attention. If handled properly this could help to raise productivity. They stated, “Vertical storage is dangerous and inefficient. Horizontal storage is preferred for safety and productivity. People tend to think vertical storage can find plates easily. But picking up a plate from vertical storage needs a stage since height of plated edge is more than 2 meters and setting a plate on horizontal cutting bed is risky and time consuming. In addition, cramping dent take place. Undertaking grinding, horizontal storage with good planning will save lot of material handling time.
Several other useful tips were presented also. Among them was cutting facilities which have seen a tremendous change over the past forty years. The knowledge of proper usage of cutting machines it was pointed out could save enormous time. In particular it is necessary to know how to minimize heat deformation / accuracy in controlling cutting / maintenance of the equipment, proper usage of CNC machine, quality of CNC code, speed and scope of NC marking.
Appropriate handling of scrap and the balance material can go a long way in saving time. Prudence in segregation contributes to productivity of sub-assembly and assembly lots. The use of CNC plasma with bevel cutting function is preferred so too 100% Hydrogen Gas cutters. The running cost is lower than LPG and cutting speed faster.
Generally painting is perceived to be easy and hence the tendency to engage beginners for this task. This greatly brings down productivity. Hence a radical change in our thinking was needed with regard blasting / painting since this could seriously tell on productivity.
Another aspect that is often overlooked was scaffoldings. These are used several times in a day and good planning and execution of the operations can save a lot of time.
Good planning and good coordination needs whole knowledge of shipbuilding. Productivity is behavioral pattern (some general, some situation-specific) that can help us get things done more efficiently.