piston design - Copy

Piston Design

1 Piston Designs Ltd Invoice No.

Document No.

# 713204

SR20DE PISTON The following is a release document for a piston for a Nissan SR20DE/SR20DET engine. The pistons are to be forged from 4032-T6 aluminum and then machined to the desired shape.

Prepared By:

To Be Checked By:

To Be Approved By:

Document No.

# 713204 Page 2 of 5

Document No.

# 713204 Page 3 of 5 INTRODUCTION The pistons are designed for a Nissan SR20DE / SR20DET engine, they are to be forged from 4032-T6 aluminum and then machined to the desired shape. They are 86.5mm in diameter, 60mm in height, and have a compression height of 32mm.

MACHINING AND CUTTING Rods of 4032-T6 aluminum alloy 86.5mm in diameter should be cut into 60mm long slugs. The punch press and die should be heated to the same temperature as the slugs. Once the forgings have cooled they are required to be heat treated twice more, the second time at a lower temperature then the first. The pistons need to be machined on a lathe to ensure they are dimensionally correct; four holes on each side need to be drilled, each 2.4mm in diameter, for lubrication. Grooves then need to be cut for the two compression rings and one oil control ring. A 22mm diameter hole needs to be drilled for the wrist pin and then the sides need to be shaved, this hole should then be smoothed and the lock ring grooves at both ends need to be cut. The dish on the head of the piston should then be cut, and then the model and production should be engraved on the piston head.

SPECIFICATIONS AND TOLERANCES The piston must be very precise dimensionally as it will expand while in use. The piston is designed to be 86.5mm in diameter and 60mm in length. The wrist pin is 22mm in diameter with a 1.2mm diameter lock ring at both ends. The piston must have a compression height of 32mm and an overall weight of 500g . Refer to the attached sheet for specific dimensions. The batches of the end product must be very similar in weight; therefore these tolerances must be kept.

SURFACE FINISH Where necessary a finishing cut of 0.15mm should be applied. All sharp edges are to be belt sanded and each piston is to be inspected for any imperfections. All traces of lubricant are to be removed by the use of high pressure jets spraying hot de-ionized water and then dried with an air gun. Each piston is to be inspected by man for any imperfections; if the piston passes the inspection it is to be packaged securely for storage and shipping.

Document No.

# 713204 Page 4 of 5 MATERIALS Pistons are to be forged from Aluminum 4032-T6, the main composition of this is as follows: Aluminum 81.1 – 87.2% Silicon 11.0 – 13.5% The following elements are also present in amounts up to 1.30%: Chromium, Copper, Iron, Magnesium, Nickel, and Zinc

STANDARDS AND QUALITY One in every 20 slugs should be inspected once it has been forged to ensure it is dimensionally accurate. The pistons are to meet the ISO 9001:2008 standards in quality manufacturing. All pistons must have a clean surface, free of lubrication, and must be in the weight error range of ± 0.1%

REFERENCES ISO Standard http://www.iso.org/iso/catalogue_detail?csnumber=46486 Material Datasheet http://www.matweb.com/search/datasheet.aspx?matguid=35707660584d4f7caef591324e592396&ck ck=1

VIEWS

Document No.

# 713204 Page 5 of 5 REASONS FOR SPECIFIC MANUFACTURING PROCESS Machining and Cutting The forging process reduces the overall process time by providing a rough shape. The CNC machining processes have to be very accurate to ensure that the tolerances are kept to a minimum and therefore the weight of each piston is kept the same.

Specifications and Tolerances The pistons must be kept within the dimensional tolerance of is kept within the .

to ensure that the overall weight

Surface Finish Before the pistons are packaged they are to be inspected by man for any imperfections, this is to ensure safety and quality as any scratch may result in fracture and/or engine damage.

Materials Aluminum 4032-T6 has an excellent surface finish when using polycrystalline or carbide tooling. It has superior wear resistance, high strength, and low thermal expansion.

Standards and Quality One in every 20 slugs should be inspected once it has been forged to ensure it is dimensionally accurate. The pistons are to meet the ISO 9001:2008 standards in quality manufacturing. All pistons must have a clean surface, free of lubrication, and must be in the weight error range of .