framework
Pump Design Engineer

This could be a form of a usual inquiry for a pump OEM.

The required flow is “---“ cubic meters per hour (m3/hr) and head required is “---“ meters. The operating medium is “----.“ The operating temperature of the liquid is “---“ C. The pump is to be supplied with a mechanical seal. The pumps will be operating in parallel with operating mode 3 x 50%. The operating speed is “…….”

These operational parameters, however, could be always changing and presenting new challenges to the manufacturers. Of course, there will be many other competitors who will be able to supply these configurations at the same time.

As such, the market scenario always puts pressure on manufacturers to have reduced delivery times, reduced costs, highest quality and excellent aftermarket services. The specific design to suit the customer-specific requirements is necessary from a customer’s point of view, where reducing the varieties and making the production easier and more efficient to increase profits is the aim of the manufacturer.

This calls for necessary changes in the product development strategy. Traditionally, the concept of a specific design to suit customer requirements is popularly used in the industry. However, the cycle time is long right from the offer stage. The sales team is an interface between the customer and the manufacturer. Hence, being quickly responsive to the customer’s inquiry is of utmost importance in terms of customer satisfaction, and the product development strategy that is adopted within the organization largely determines how this response will be. So, in order to enable the sales team to be quickly responsive, it is essential to have a modular concept implemented during the series development of new products.

In principle, the product can be categorized as make-to-stock and engineer/make-to-order. The make-to-stock is out of question. The necessity of this concept comes into play for the second category: make/engineer-to-order scenario. The concept of modularity can be defined as “the practice of using standardized modules so that they can be easily reassembled or rearranged into different functional forms, or shared across different product lines.”

The concept is generic and can be implemented across a wide array of products. The importance lies not in the implement of modularity but rather in the implementation of degree of modularity. Being a pump equipment manufacturer, the degree of modularity plays a vital role. The identification of functional requirements and technical features of a product is necessary. The functional requirements are the requirements of the customers or, in other words, operating parameters of the pump. Technical features are the description of the product as whole. For example, the product can have the same technical features for more than one functional requirement. So, to achieve the desired degree of modularity, it is essential to control the technical features.

The pump can be divided into different modules and designed so that function of one module shall not depend upon the function of another module. These modules combined define the technical features of the pump. For example, the sealing system of the pump is dependent upon the operating medium, temperature of the operating medium, pressure to be sealed and operating speed. The sealing system is not dependent upon the flow or individual head developed by one impeller, single stage or multistage pump, etc. Hence, the product should be designed in such a way that there is minimum design effort required and that effort should be focused on the required functional need while the rest of the components that do not depend upon that functional need shall not be required to change just because it is connected to the module. The module is being affected due to that functional need or the change in operating parameters.

The pump is equipment that moves the liquid from one point to another point into the system. So, it can be viewed simply as a pipe for the time being. The pipes are designated by their diameter nominal (DN) size. The pump ultimately has to begin and terminate between the pipes. Hence, DN size for pump termination points is an important feature. This is something essentially seen as a part of designation for most pump types across all of the OENs. So, the pump size will be the function of the flow of the liquid, which will move across it. In order to implement the concept of modularity successfully, one must identify the typical features of the pump. There could be various ways through which one can simplify the process of variant design.

One such example could be using encryption. Encryption is the process of encoding available information. Using such a technique, one can convert the available information to fit in one single code, which can be then deciphered. The advantages of having such a process are enormous. Hence, it is necessary to first ensure the features of the product on which the encryption will depend. This will not only ease the process of design, but also it will allow the users to access the available data into the system.

So, such encryption could be representing a product with certain digit code and assigning a particular product feature for every digit of the code. For example, representing a pump with five digits, where the first digit could be size of the pump, second could be impeller/diffuser combination, third digit could be type of bearing, fourth could be materials to used and so on. So, when considering each digit is having three variants, i.e., three possible designs, then it means that there are, in total, 5 x 3 = 15 different combinations, i.e., variants of that product series. The focus is clear, right in the beginning, where to start. It means that if only the second digit is different than the previous executed order, then the focus is only to change the hydraulic module to suit the requirement, keeping the rest of the components as they are from the previous data. One more notable fact is that the accurate indexing through the system is possible since the code will trace the exact design available into the system.                      

IMAGE 2: Framework of Implementation of Modular concept

IMAGE 1: Framework of implementation of modular concept (Image courtesy of the author)

The modularization also brings one more advantage: parameterization. The parameterization in terms of designing and drafting through the use of computer-aided design (CAD) software. The CAD software has potential to reduce design efforts and time that might go mostly unused. Because of the modularization and standardization of modules, it is possible to make efficient use of CAD programming such as preparing user-specific commands, making use of dynamic inputs to configure product, configuring modules using programs, etc. This reduces the time to prepare the project-specific drawings such as cross-section drawings.

These are the advantages concerning the design. There are also many advantages with regards to manufacturing and inventory management as well. One can scale these advantages even up-to supplier developments and green channels as well.

Implementation of modularity is a complex task and requires great effort in the initial stages of product development. It also requires higher dedication and discipline to follow the established system with no tolerance to bypass the system. Also, efficient market study and customer-centric approach is needed in order to formulate the possible variants. These will simplify the later task of modularization and standardization.