crankshaft journal machining Archives

Crankshaft Journal Machining of YANMAR 6N18AL-DV | YANMAR Engine Repair

We were approached by a company based in Greece reporting the failure of a crankshaft of auxiliary engine on one of their vessels operating in the Gulf.

It was reported that the accident resulted in the failure of the bearing of crankpin no. 1, 3, and 6.

DETAILS OF YANMAR 6N18AL-DV ARE AS FOLLOWING:-

S. NO	Crankshaft Details
1	Engine Make	YANMAR
2	Engine Model	6N18AL-DV
3	Crankpin Diameter Standard	145 mm
4	Crankpin Bearing Width	65 mm
5	Name of Vessel	MV GULF Traders

Our team of two technicians boarded the vessel in short notice and requested the chief engineer to open the connecting rod of all six crankpins.

THE CRANKPINS AFTER CLEANING WERE SUBJECT TO DIMENSIONAL INSPECTION AND FOLLOWING DIMENSIONS WERE OBSERVED:-

STANDARD DIMENSION: 145.00 mm

STANDARD /SPECIFIED NO

SIZE OF CR PINS

	A	Aa	C	Cc	B	Bb	Min	Max	Remarks
CR-1	144.66	144.83	144.77	144.82	144.69	144.82	144.66	144.83	Ovality – 0.17 MM
CR-2	144.64	144.77	144.79	144.81	144.65	144.73	144.64	144.81	Ovality – 0.17 MM
CR-3	144.69	144.76	144.76	144.83	144.64	144.81	144.64	144.83	Ovality – 0.19 MM
CR-4	144.61	144.74	144.74	144.79	144.68	144.75	144.61	144.79	Ovality – 0.18 MM
CR-5	144.66	144.81	144.77	144.84	144.71	144.73	144.66	144.84	Ovality – 0.18 MM
CR-6	144.67	144.85	144.78	144.80	144.72	144.77	144.67	144.85	Ovality – 0.18 MM

On going through the above dimensions, it was noticed all 6 crank pins had ovality between 0.17 mm to 0.18 mm and were considerable down in comparison to standard diameter of 145.00 mm.
The hardness of crank pins was checked with a portable hardness tester and was observed within limits.
The MPI was conducted by our level 2 qualified technician.
Multiple hairline cracks were observed on crank pin no.4 having a length ranging from 6 mm to 25 mm.

REPAIRS UNDERTAKEN BY RA POWER SOLUTIONS:-

Considering the ovality , multiple cracks on crank pin nos 4 and rough surface observed of YANMAR 6N18AL-DV.
All the six crankpins except crankpin no. 4 were undersized to 0.80 mm. The crank pin no. 4 has to be undersized by 1.20 mm due to the presence of cracks.

THE FINAL DIMENSIONS MAINTAINED AFTER GRINDING OF CRANK PINS IS MENTIONED BELOW:-

STANDARD DIMENSION: 145.00 mm

STANDARD /SPECIFIED NO

SIZE OF CR PINS

	A	Aa	C	Cc	B	Bb	Min	Max	Remarks
CR-1	144.19	144.20	144.18	144.18	144.19	144.20	144.18	144.20	Ovality – 0.02 MM
CR-2	144.20	144.19	144.19	144.18	144.20	144.19	144.18	144.20	Ovality – 0.02 MM
CR-3	144.20	144.18	144.19	144.19	144.20	144.18	144.18	144.20	Ovality – 0.02 MM
CR-4	143.80	143.80	143.79	143.78	143.80	143.79	143.78	143.80	Ovality – 0.02 MM
CR-5	144.20	144.20	144.19	144.18	144.20	144.19	144.18	144.20	Ovality – 0.02 MM
CR-6	144.20	144.19	144.18	144.18	144.20	144.20	144.18	144.20	Ovality – 0.02 MM

SUPPLY OF UNDERSIZE BEARINGS OF YANMAR 6N18AL-DV BY RA POWER SOLUTIONS:-

The 0.80 mm and 1.20 mm under-size bearings were supplied by RA Power Solutions in a very short time and engine was put back into operation.
We maintain a large stock of spare parts of YANMAR 6N18AL-DV or arrange through our principals on short notice.

THE MAIN FEATURES OF REPAIR OF CRANKSHAFT OF YANMAR 6N18AL-DV:-

The crankpin having a diameter of 145 mm and a bearing length of only 65 mm was successfully repaired by us because of the fact, we have a dedicated crankshaft grinding machine which can undertake the grinding of crank pin having a small diameters and bearing widths.

Most of the companies based in Europe and other countries do not have the equipment which can on-site grind the crank pin and main journal diameter having a small diameter and bearing width. They advise clients to open the crankshaft from engine and send it to the workshop for repairs.

We extend our services all over the world at a very low price.

**Crankshaft Machining of YANMAR 6N18AL-DV on vessel**

**Onsite Crankshaft Grinding of YANMAR 6N18AL-DV**

**Insitu Crankshaft Pin journal Repair of YANMAR 6N18AL-DV**

**Crankshaft after Grinding and Polishing**

MAK , B&W , Sulzer , Bergen , Detroit Diesel ,Stork Werkspoor , Pielstick , Deutz , Yanmar , MTU , Cummins , Nohab Polar , Caterpillar , Mitsubishi , Yanmar , MAK and many more.

We have been regularly executing the repairs in Armenia, Azerbaijan, Bahrain, Bangladesh, Bhutan, Brunei, Cambodia, China, Cyprus, Georgia, Indonesia, Iran, Iraq, Israel, Japan, Jordan, Kazakhstan, Kuwait, Kyrgyzstan, etc.

This blog is written by Mr. Raj Shahani (Managing Director of RA Power Solutions India Pvt. Ltd.).
Mr. Shahani is a highly experienced business leader with rich experience of more than 40 years in the field of Power, Heavy and Shipping industries. He is Technical Adviser to many shipping and heavy industries across the globe.

Mr. Shahani is one of the most enthusiastic professional and he has all the brilliance of an exemplary leader. Mr. Shahani is an extremely effective coach and mentor of teams and is adept at providing leadership in a global, cross-cultural environment.

For more information on crankshaft repair, crankpin repair, and yanmar engine repair contact us at rajshahani@rapowersolutions.com or info@rapowersolutions.com or call us at +91 9582647131 or +91 9810012383.

Hand Polishing of Crankshaft Journals | Crankshaft Grinding Equipment | Main Journal Grinding

The crankshaft is the heart of the engine and is the most important/expensive component. It is necessary that the crankpin journal and main journal of the crankshaft are periodically inspected and polished. This not only enhances the life of the bearing but saves the crankshaft from any damage in case it is properly polished.

The oil film between the crankpin/main journal and bearings is too thin while the engine is in operation. In case the main journal and crankpin have roughness, burr, pitting, and line marks it can result in the discontinuation of oil film and failure of bearing causing damage to the crankshaft.

RA Power Solutions during the working on crankshafts of marine Engines for the last four decades have observed that non-conventional methods for polishing of main journal and crank pin journal are adopted to put the engine back in operation.

The non-conventional methods used are as follows:

I) Polishing of crankpin journal and main journal by Jute rope.
II) Polishing of crankpin journal and main journal by various grinding and polishing mediums.

**Consequences of Hand Polishing on Crankpin**

We observed that following these unconventional and nontechnical processes for polishing the crankshaft does not remove the line marks or the various other abnormalities which do get developed. In some cases, since this process has no control excessive taper and ovality are created resulting in the failure of the bearing and crankshaft.

Crankpin and Main Journal Polishing Made Easy:

RA Power Solutions by introducing a lightweight, compact onsite crankshaft polishing machine has made the crankshaft repair process simple with minimum downtime of the engine. The polishing and grinding machine are inserted from the engine block and a polishing crankpin is undertaken. The onsite crankshaft grinding and polishing machine is capable of maintaining a surface finish better than the international standards i.e. 0.2 RA value.

**Grinding of Crankpin by Onsite Crankshaft Grinder on Vessel**

**Crankshaft Grinding and Polishing Machine**

Suggestions:

RA Power Solutions strongly suggest that the polishing of the crankpin should be undertaken periodically as a routine maintenance process. This will not only extend the life of the bearings but also save the crankshaft from any major breakdown.

We offer two options to our clients either they can call our technicians who will visit their site with the portable on-site Crankshaft polishing equipment and undertake the polishing of the crankshaft. Alternatively, we also manufacture onsite crankshaft polishing machines which are simple to operate. More than 70 onsite crankshaft grinding and polishing machines have been sold all over the world.

**Crankpin After Grinding of Crankshaft**

RA Power Solutions offers a cutting-edge crankshaft polisher machine that revolutionizes the process of crankshaft polishing. The crankshaft polisher machine is designed to enhance the crankshaft’s performance, durability, and overall efficiency, ultimately optimizing the engine’s performance.

Our commitment to quality and innovation makes their crankshaft polisher machine a go-to solution for clients seeking top-notch results. Trust in RA Power Solutions to deliver excellence in crankshaft polishing, meeting the highest industry standards and exceeding customer expectations.

This blog is written by Mr. Raj Shahani (Managing Director of RA Power Solutions) having more than forty years of experience in the field of onsite repair of high-capacity engines. After extensive trials and research, he has developed onsite crankshaft grinding and polishing equipment for saving the crankshaft from rejection.

For any queries about main journal grinding, onsite crankshaft polishing services, crankshaft journal machining, and Crankshaft Polisher machine please email us at rajshahani@rapowersolutions.com, or info@rapowersolutions.com, or call us at +91 9582647131 or +91 9810012383.

Onsite Crankshaft Grinding Machine | Insitu Crankshaft Polishing and Grinding Machine | Crankshaft Machining – RA Power Solutions

In case of accident of Crankshaft in recent past, it was necessary to disassemble the crankshaft from the engine block or housing, pack it and send it to the designated workshop.

The Introduction of Onsite Crankshaft Grinding Machine, Insitu Crankshaft Polishing and Grinding Machine, and Crankshaft Machining, there is no need of removing the Crankshaft and sending it to the work shop as now it is possible to undertake crankshaft grinding and crankshaft repair with revolutionary design of Onsite Crankshaft Grinding Machines manufactured by RA Power solutions.

The Onsite Crankshaft Grinding Machine has been developed out of our experience of Crankshaft repair of Forty Years. The Machine is Lightweight and can be taken to the Site. It has the following Features.

Onsite Crankshaft Grinding Machine, Insitu Crankshaft Polishing, and Grinding Machine is manufactured by RAP after extensive research, development, and our experience.
The Machine in the Initial Years was used by our technicians for In-house applications. Now from last ten years Machine is sold in open market all over the world.
The Insitu Crankshaft Grinding and Polishing Machine is user-friendly and can be operated by any person having basic machining knowledge.
The Machine is capable and is designed to maintain the close dimensions and Geometrical tolerances as per the manufacturers requirement.
Presently Onsite Crankshaft Grinding Machine is manufactured for the diameter of the Crank-pin and Main Journal of the Crankshaft ranging from 30 mm to 700 mm.
Crankshaft Grinding Machine is manufactured out of Titanium Alloy which is lightweight and can be easily carried to the Site.
The Machine is capable of working on a Vessel while it is moving.
Training forms an integral part of the Crankshaft Grinding Machine. Training onsite is provided.
We have sold more than seventy machines all over the world and are priced cheapest in the International Market.

Onsite Crankshaft Grinding Machine Ready for Dispatch

Onsite Grinding Machine for Small Diameter

For more details on insitu crankshaft grinding equipment, portable crankshaft grinding machine or onsite crankshaft grinding and polishing please email us at rajshahani@rapowersolutions.com, or info@rapowersolutions.com, or call us at +91 9582647131 or +91 9810012383.

Introduction to RA Power Solutions Pvt. Ltd., India

Company is providing on site repairs of major components of diesel engine, pumps, compressors and all type of rotary equipments mainly crankshaft, engine block, cylinder heads, liners. The repairs are undertaken by trained and experienced technicians equipped with latest breed of specially designed and developed portable machining equipments. Repairs are executed strictly as per the guidelines and tolerances stipulated by the manufacturers. Company is involved in supplying spare parts and supporting equipments used in diesel power plant. The parts and the supporting equipments are directly sourced from the OEMs and are competitively priced. White metal bearings are manufactured as per the drawing or sample. Rebabbitting of old bearing is undertaken by centrifugal process. The white metal used is sourced from the reputed companies and in house facilities for quality checks are in place.

For more details regarding onsite crankshaft grinding, in situ crankshaft grinding machine, rebabbitting of bearing, engine overhauling, and engine block repair, please email us at rajshahani@rapowersolutions.com, or info@rapowersolutions.com, or call us at +91 9582647131 or +91 9810012383.