Question 1

What Is Crankshaft Machining?

Accepted Answer

The Nicol & Andrew Group has been crankshafts machining in-situ, even very large ones over 1M in diameter, since 1950. In fact, we invented & patented the Orbitool machining systems back then. Our crankshaft machining and repair service utilize the latest in orbital machining technology developed over the past 60 years. Our crankpin and main journal repair technicians must be highly trained to work onsite.

This training takes many years to complete, & their ultimate level of skill is quite frankly amazing. It should be this way because there is no margin for error when machining a crankshaft on site. We have a very competent supervisor and a team of technicians who love to be involved in the refurbishment of the crankshaft, crankpin, and main journal bearings, on land-based sites and also on sea-going vessels.

We also have offshore trained engineers capable of traveling to offshore platforms anywhere in the world. The crankshafts are an essential part of the power transmission system. In which the reciprocating motion of the piston is converted into rotational motion by using a connecting rod.

Question 2

Crankshaft Machining:

Accepted Answer

The manufacture of the crankshaft is not a straightforward matter; Many pitfalls await for the daring novice attempting to build their own crankshaft, and there are reasons why there are so few reputable race crankshaft manufacturers. The general tendency to try to reduce engine friction means that modern design practice is often towards reducing bearing diameter.

This means that more cares need to be taken in construction, especially heat treatment if serious deformation is to be avoided. Manufacturing stress, with surfaces typically under stress by the sheer action of machining, means that heat treatment has the potential for deformation where these are excessive.

The traditional method of rough-machining of the crankshaft was to turn each crankpin on a large, sturdy mandrel with the crankpin in the center and the central axis of the crankshaft offsetting half of the crank stroke. The forces involved were considerable, and machining was time-consuming. The advent of modern machining inserts has improved things, but this type of tool does not forgive the type of intermittent cutting that often results from eccentric turning.

Question 3

Method of Crankshaft Machining:

Accepted Answer

Modern machining methods have also improved manufacturing accuracy and reduced the amount of manual dressing of facilities. Features that previously required careful manual processing were the edges of the bevels between the crankpins and the main bearings, as well as oil holes.

Both types of features are now commonly eliminated by CNC machining methods, and the surfaces of crank-bevel features are no longer limited to swept surfaces defined by eccentric machining on the lathe. The consistency of oil-hole dressing is very important, as these characteristics are often the weak point of the crankshaft as far as fatigue is concerned, and it is likely that incorrect oil-hole preparation – or even Forgetting to prepare a hole - would render an otherwise optimal crankshaft unsuitable for use.

Where the edges of oil shavings are machined, there should be no excuse for not having the consistency of form and finish prior to nitriding. The use of 3D machined surfaces, courtesy of modern CNC machining processes, opens the door to more complex shapes and for the crankshaft designer to design lightweight crankshafts that, with some consideration in the design and analysis process, can be more resistant.

Question 4

Tools Used in Crankshaft Machining:

Accepted Answer

As a sole manufacturer, Hegenscheidt-MFD provides its customers with machine tools and tools used in crankshaft machining from a single source. Our experts in design, sales, and service will work with your company's specialist departments on innovative and optimal machining processes for deep rolling main and pin bearings, and rolling plane surfaces on flange bearings.

Scope:- Process planning for deep rolling and finish rolling, Our own equipment design and development, Our own equipment production, 100% Quality Control, Training of personnel in equipment preparation, Process optimization to increase equipment service life, Our own test ground for test machining of crankshafts, Our own stand-alone oscillation test to determine the fatigue strength of the component.

Benefits at a Glance:- Extensive service package from technical support for the machine to the services provided to the tool - all from a competent source, ensuring maximum process reliability, Extensive expertise in process design, Systematization, and development of equipment systems for optimum conservation of resources in crankshaft production, low cost of input.

Question 5

Parts of Crankshaft Machining:

Accepted Answer

#1. Crankpin

The crankpin is a mechanical part of the engine, which allows the connecting rod to be very firmly attached to the crankshaft. The surface of the crankpin is cylindrical, which imparts rotational forces to the large end of the connecting rods. These are also known as connecting rods journals.

#2. Thrust Washers

At some points, two or more thrusts washers are provided to prevent the crankshaft from increasing in length. These thrust washers are assembled in the web between the machined surfaces & the crankshaft saddle. With the help of thrusts washers, it can easily be maintained the gap and helps in reducing the lateral movement of the crankshaft. In many engines, these are built-in as part of the main bearings, usually the older type, using separate washers.

Question 6

Types of Crankshafts Machining:

Accepted Answer

#1. Fully Built Shaft

This type of crankshaft is made by joining parts together. In this, after the manufacturing process, all the components are shrunk and fitted. This type of crankshaft is used in older engines. It consists of a separate crank web, crankpin, and main journal.

This crankpin and journal are machined and bored into the crank web. They are slightly smaller in diameter. The crank webs were heated and fitted into the crankpin and journal hole, which expanded in size due to the heat. As the crank web cools, the diameters of the borehole will attempt to shrink back to their original size.

#2. Forged Crankshaft

These are much stronger than cast cranks. Forged cranks are commonly used in high-tension engines and some 16 valve engines. They are designed in completely different ways. A set of dies are formed for the approximate size of the crank.

These rest in a large hydraulic press which has clamping forces of several tons. Once the die is closed, the metals are pressed very tightly. This type of crankshaft is stronger and more durable. Forged crankshafts react to heat treatment & thus give betters dimensional stability.

Question 7

Construction of Crankshaft Machining:

Accepted Answer

Inside the crankshaft, it houses the main bearings, also known as the main journal. The crankshaft is supported by the main bearing on the main magazines. A balanced load is provided on the opposite side of the crankarm for balancing. A crankshaft is typically manufactured from alloy steel by a casting or forging process and machined and grounded to give a suitable journal for the connecting rod and main bearing.

Question 8

Faults of Crankshaft Machining:

Accepted Answer

Problems are rarely seen on the crankshaft. This happens when the engine is going through extreme conditions. Engine parts are strong and sturdy. But they include some basic drawbacks:

#1. Warne Journals

This usually happens when enough oil pressure is not available. If the crankshaft journal makes contact with the bearing surfaces, it gradually increases the clearance and degrades the oil pressure.

If this is not taken care of, worn-out journals can cause serious problems for the engine. This destroys the bearings & causes heavy damage to the engine.

#2. Fatigue

This is when the constant force on the crankshaft leads to breakdown. This problem usually occurs on fillets where the journal and web are involved. A smooth surface of the fillet is essential to avoid weak spots causing fatigue cracks. Cracks can be inspected using Magnas-fluxing on the crankshafts.

Question 9

Applications of Crankshaft Machining:

Accepted Answer

The crankshafts are commonly used in an engine to convert reciprocating motion into circulars motions, making the use of energy or power much easier. Crankshafts machining is actually the heart of an internal combustion engine.

The crankshaft Machining is responsible for the proper operations of the engine. In some circumstances, it also saves energy to move the pistons for the compression, suction, and exhaust strokes.

What Is Crankshaft Machining? | Crankshaft Machining | Method of Crankshaft Machining | Parts of Crankshaft Machining