LNM Auto Blog

Official Blog of LNM Auto Industries Pvt. Ltd.

Some more on Conical Bit

Since last two posts have been revolving around conical bit (cutter pick), I thought to continue Sandeep’s flow and add some more on the cutter picks. The presentation will give glimpse of various forms, sizes and types of conical bits that me manufacture and export.


October 17, 2007 Posted by | Products, Uncategorized | | Leave a comment

Team Spirit

I was visiting some exhibition on construction and mining in Bangalore a few years back and came across a German Company Wirtgen. I knew and had heard about Wirtgen but never knew they had a sales and service setup in India by the name of  Wirtgen India Pvt Ltd. Wirtgen GmbH, a world leader in manufacturing Road Construction and Mining Equipment, manufactures a wide range of Cold Milling Machines, Cold Recyclers, Soil Stabilizers, Hot Recyclers, Surface Miners, Slipform Concrete Pavers and Mobile Cold Recycling Mixing Plant. They are a big buyer of Conical Bits and were sourcing there requirements mostly from their parent company in Germany. I had the opportunity to meet one of there senior guys, Pankaj Kumar. Pankaj a north India was speaking fluent Bengali which surprised me. Fortunately being born and brought up in West Bengal and having done my schooling at Ramakrishna Mission I also speak, write and read Bengali. So we struck a good rapport. We kept discussing their requirements for Conical Bits. Pankaj invited me to there sales and service warehouse in Bangalore. I reached there facility on the scheduled time and date. It was a very pleasant welcome and the major agenda was supply of Brazed Conical Bit for wirtgen machines in India. Wirtgen that point of time had almost 50 machines working in India. After our meeting we went for lunch in there canteen and were joined by the core team including the Manging Director. There were people from all across the country including Kashmir and also a sardarji. What was surprising there to me was all of these guys were speaking fluent Bengali and that too in the state of Karnataka. Later on I came to know this whole group has been working together for last many years in a different company and then joined here in mass with the managing Director and there MD happened to be a Bengali guy and rest of the team picked up the language for the leader. What a team spirit!

October 16, 2007 Posted by | Experience | | 1 Comment



Enterprise Resource Planning systems (ERPs) integrate all data and processes of an organization into a unified system.  A typical ERP system will use multiple components of computer software and hardware to achieve the integration. A key ingredient of most ERP systems is the use of a unified database to store data for the various system modules

The introduction of an ERP system to replace two or more independent applications eliminates the need for external interfaces previously required between systems, and provides additional benefits that range from standardization and lower maintenance (one system instead of two or more) to easier and/or greater reporting capabilities (as all data is typically kept in one database).

Examples of modules in an ERP which formerly would have been stand-alone applications include: Manufacturing, Supply Chain, Financials, Customer Relationship Management (CRM), Human Resources, Warehouse Management and Decision Support System.

Ideally, ERP delivers a single database that contains all data for the software modules, which would include:


Engineering, Bills of Material, Scheduling, Capacity, Workflow Management, Quality Control, Cost Management, Manufacturing Process, Manufacturing Projects, Manufacturing Flow

Supply Chain Management  

Inventory, Order Entry, Purchasing, Product Configuration, Supply Chain Planning, Supplier Scheduling, Inspection of goods, Claim Processing, Commission Calculation


General Ledger, Cash Management, Accounts Payable, Accounts Receivable, Fixed Assets


Costing, Billing, Time and Expense, Activity Management

Human Resources  

Human Resources, Payroll, Training, Time & Attendance, Benefits

Customer Relationship Management  

Sales and Marketing, Commissions, Service, Customer Contact and Call Center support

Data Warehouse  

Various Self-Service interfaces for Customers, Suppliers, and Employees


LNM uses ERP to manage all the activities like engineering, production, material handling,  inventory management etc.

October 15, 2007 Posted by | Experience, Quality Control | Leave a comment

Conical Bit

Conical Bit or Cutter Pick

Conical Bit :

A miner bit has a base portion formed of two different metallic members welded together, one being adapted to be mounted to a continuous mining machine and the other having a frustoconical end portion welded to a frustoconical tungsten carbide bit.

Its called differently by different people and companies. Some call it Bits, Pick, Cutter pick etc.

The body of this conical bit is made of steel casting or forging having a conical nose end position provided with an axial hole in the front in which a tungsten carbide insert is mounted. The tungsten carbide insert extends from the front end of the nose portion of the metal body and provides the cutting surface of the bit. These conicals are mounted on Blocks which are also called Pick Box, Bit holder etc.. In use a large number of such bits are mounted for free axial rotation in the outer surface of a rotary drum, or in the outer surface of a continuous chain or the like, and the bits are moved through an orbit which is intercepted by the face of the material being mined .

The conical Bit also has a groove in the bottom side in which a retainer is attached for the conical to remain fitted into the bit block.

LNM has been making these conical bits for last 8 years having a capacity to make almost 1.5 million of them a year. Usually we make them out of different alloy steel hot or cold forged and then machined and heat treated.

October 15, 2007 Posted by | Experience, Products | , , , | Leave a comment

Quality Control at LNM Auto

Not be left Behind in show casing how we manage Quality Control we take this opportunity to introduce one of our Quality Control machines for testing hardness-

LNM Auto has installed MIRO HARDNESS TESTER model of M/S CHROMA SYSTEMS. The tester is used for micro loads ranging from 100 gms. to 3000 gms. for estimation of VICKERS HARDNESS using a diamond pyramid indenter. The tester is accomplished by a software computer interfaced for auto measurement and reporting.

The operation involves keeping the polished specimen on the table of the tester and the numbers of impressions by indenter are programmed at fixed interval of the distance from surface. The impressions are measured for two diagonals of the pyramid automatically for Vickers’s hardness. The software gives the graph of Hardness v/s Distance. The effective case depth is automatically calculated by feeding the cut off value in the software.

Major applications involves Effective Core Depth (ECD) measurement of case carburised parts, Decarb & Partial decarb values, hardness of very small and thin parts.

Here is a Typical Report format that we share with our customers lnm-quality-controlmicrohardnessanalysis.pdf

The Beauty for your eyes :=)


September 28, 2007 Posted by | Quality Control | , | Leave a comment


Beginning today I will be sharing the some of the manufacturing processes with the readers of our blog. It is so important to know how we are able to produce with precision what we do for our consumers. Today I will talk about Forging process.

Forging is the working of metal by plastic deformation The processes of raising, sinking, rolling, swaging, drawing and upsetting are essentially forging operations although they are not commonly so called because of the special techniques and tooling they require.
Forging results in metal that is stronger than cast or machined metal parts. This is because during forging the metal’s grain flow changes into the shape of the part, making it stronger. Some modern parts require a specific grain flow to ensure the strength and reliability of the part.
Many metals are forged cold, but iron and its alloys are almost always forged hot. This is for two reasons: first, if work hardening were allowed to progress, hard materials such as iron and steel would become extremely difficult to work with; secondly, most steel alloys can be hardened by heat treatments, such as by the formation of martensite, rather than cold forging. Alloys that are amenable to precipitation hardening, such as most structural alloys of aluminium and titanium, can also be forged hot, then made strong once they achieve their final shape. Other materials must be strengthened by the forging process itself.
Forging was done historically by a smith using hammer and anvil, and though the use of water power in the production and working of iron dates to the 12th century CE, the hammer and anvil are not obsolete. The smithy has evolved over centuries to the forge shop with engineered processes, production equipment, tooling, raw materials and products to meet the demands of modern industry.
In modern times, industrial forging is done either with presses or with hammers powered by compressed air, electricity, hydraulics or steam. These hammers are large, having reciprocating weights in the thousands of pounds. Smaller power hammers, 500 pounds or less reciprocating weight, and hydraulic presses are common in art smithies as well. Steam hammers are becoming obsolete.
In industry a distinction is made between open- and closed-die forging. In open-die work the metal is free to move except where contacted by the hammer, anvil, or other (often hand-held) tooling. In closed-die work the material is placed in a die resembling a mold, which it is forced to fill by the application of pressure. Many common objects, like wrenches and crankshafts, are produced by closed-die forging, which is well suited to mass production. Open-die forging lends itself to short runs and is appropriate for art smithing and custom work.
Closed-die forging is more expensive for mass production than is casting, but produces a much stronger part, and is used for tools, high strength machine parts and the like. Forgings are commonly used in automotive applications, where high strength is demanded, with a constraint on the mass of the part (high strength-to-mass ratio). Forged parts are more suitable for mass production. The process of forging a part becomes cheaper with higher volumes. For these reasons forgings are used in the automotive industry, usually after some machining. One particular variant, drop forging, is often used to mass produce flat wrenches and other household tools.

LNM is into these two types of forging processes.

Hydraulic press forge
In hydraulic press forging the work piece is pressed between the two die halves with gradually increasing force, over a period of a few seconds. The quality of the pieces is better than drop forging as there is more control over metal flow, but takes longer and requires more energy. It also makes the same shape continuously


Hot forging
Forging is the hammering or forming of hot or cold metal into a certain shape. When the hammering and forming is done by hand it is called hand forging and when it is done by machine it is called drop forging. The forging process starts after having brought the steel to the correct workable temperature between 900°C and 1100°. It allows us, through a process of reduction (for crushing), to get the most various shapes


September 28, 2007 Posted by | Manufacturing Process | | Leave a comment

Learning Curve – Set the expectations

During my last 13 years in business another lesson I have learnt is to set the customers expectation. We invariably tend to over commit. As a small scale manufacture who is always trying to grow, I have at times over committed to the customer to please him. This only helps in stretching the problem for some time but increases the problem manifold. And leads to firefighting at our end always for every thing. It’s impossible to work in firefighting situation as while doing so you are making shortcuts and bypassing the system.

In 2004 one of the customers ( I am refraining from using the name) was doing a reverse auction for there Bit Blocks in two lots. One lot was annual around 1 million dollar business and the other lot was annual around 4 million dollars. As on that day we were not prepared for any of these. The smaller lot was almost equivalent to then capacity of LNM. This required development of 16 Bit Blocks in a span of 12 weeks. And an investment of more than Rs 30.0 lacs in development only within this time period. We were not making die blocks in house at that time. We started getting in touch with job shop people to make the dies for us and were shocked to see the crude way they were doing there job and the time they wanted. They wanted almost 4 weeks for each die and this would have been disaster for LNM as we would have taken almost a year to develop all these parts. That’s when we decided to use technology and invested in CAD Cam softwares and human resources. We bought couple of Vertical Machining Centers and started making the dies in house. It was always firefighting situation and with all efforts possible we were able to deliver the Bit Block samples in time. But only developing was not the solution. We needed machines, people and vendors to be successful in making these blocks. This also resulted in delays in supply to existing customers. The whole “working in system” concept for which we were proud off got a back seat during the process. This resulted in increase of customer complaints and customer dissatisfaction. It took us almost two years to come to the level where we should have been in 2004. To cut the story short I have learnt to be truthful to our capacity and it’s always better to under commit and over deliver than vice versa. Your under commitment keeps the customers expectation low and over commitment makes him comfortable about the supplier.

August 29, 2007 Posted by | Experience, History of LNM Auto | Leave a comment

Learning Curve – Patience pays

Patience pays – Beginning of a relation

Till 1994 I was deeply involved with Rotaract and as the DRR of RI district 3290 was couldn’t give much time to work. 26th May 1995 – I landed bag and baggage at Faridabad to run LNM Auto. It was a tough period. We had a small workshop in rented premises and few conventional machines. My family was there at Purulia and here I was all alone in a new city to chart out a career for myself. Dad and his friend Raman Daga initiated LNM Auto basically with more patriotism than anything else as the country needed dollars those days. The product with which we had started was Dust Hog (used in mines for roof bolting). Dust Hogs have carbide brazed to its one end and are provided with openings into which the dust or cuttings produced by the bit as the drill advances may enter. We had set up a small line of production for these dusthogs. Our first order was for 18000 nos to be shipped in two months.

I was totally new to manufacturing. I had no idea how to measure or use a measuring instrument or for that matter what a Lathe or milling machine is. I went to lot of people for things, ideas and processes for manufacturing and was taken for a ride by most of them. Anyway our production started and we made the first 18000 parts from this new line. Dust hog had 13 machining operations to be done in its 80 gm structure. We used drawn alloy steel. It took us more than four months to make these 18000 pcs . During final inspection our foreman at that time Mr. Vinod Sinha informed and told me that there were around 400 nos in these 18000 which were not in spec and there was a deviation in one dimension. I was new into business and manufacturing. I had no idea about products application. And I only understood that I will be loosing in this batch if I had to scrap these 400 dusthogs and also will be short of the 18000 pcs quantity. I thought who is going to find out find out about these 400 nos from 18000 and asked Mr. Sinha to ship these with the 18000. It was almost two months of guilt and fear till shipment reached USA and as was to happen got rejected. Raman Daga called up to inform that the lot has been rejected as some of the parts there in has one dimension wrong. The fear came true. There was a sense of relief also as the guilt and apprehension was now over. The first consignment for export from LNM has been rejected because of my shortsightedness.

It took me some time for the shock to sink in and then I called Raman Daga. Those days Govt of India guidelines were very strict with regards to foreign remittance coming within 6 months of export and money was not to come in for the rejected lot. I saw LNM being blacklisted by the Govt before it has started. I requested Mr. Daga to send in the payment for the same otherwise I will have problems a plenty with the banks and told him some time in future I will credit this back to him. He replied back – I am sending the money and don’t want a credit back from you. THIS IS MY INVESTMENT IN YOUR LEARNING PROCESS. Never find shortcuts in business or for that matter life. It hurts more than it pays.

I have never forgotten these words and basically they still echo within me. I appreciate the foresightedness of Mr. Daga for whom the simplest thing could have been to say: Sorry , you guys are not capable of handling things and we can’t work with you”. Today wherever LNM is, it is because of the patience and foresightedness of that day shown by Raman Daga.

This was an early lesson for me in career and business. LNM at 5 million USD revenue would not have been there had Raman Daga not had this vision.

August 27, 2007 Posted by | Experience, History of LNM Auto | Leave a comment