WPC処理(精密ショットピーニング処理)In recent years, WPC treatment is an epoch-making surface treatment that is deeply related to internal combustion engines.

From the viewpoint of the processing technology cultivated over many years, NAPREC can guide you in selecting the correct processing content, so please feel free to contact us regarding processing for any part.

In particular, it will be possible to bring out the effects of WPC by synchronizing it with the processing of the internal combustion engine.

WPC treatment can be broadly divided into two types: slidability improvement (standard treatment) and fatigue strength improvement (strengthening treatment). Furthermore, it is composed of high-purity molybdenum disulfide without any additives to the surface layer of the main body. We will execute the treatment by accurately selecting (or combining) the four items of the original molybdenum shot that can be done and the SMAP treatment that can make the WPC treatment surface layer more stable.

There are a wide variety of parts that can be processed, but we will mainly guide you to the prices of typical parts that are likely to be processed in synchronization with engine processing.

*Unit: \(JPY)
*The price does not include tax.

* For pistons, refer to the piston table below.
Product Size Unit WPC Molybdenum
Piston See table below
Piston pin Uniform One 1,300
Piston ring Uniform One 700 Expander is not processed.
Rocker arm Whole processing One
1,600 2,400 WPC + SMAP processing
(MOS2 processing is not performed)
Rocker shaft Less than 200 mm in length One 1,820 2,730
Rocker shaft Length 200 mm or more One 2,860 4,290
Valve lifter Diameter less than φ40 One Piece 1,100 1,650
Valve lifter Diameter φ40 or more One Piece 1,560 2,340
valve Whole processing One 1,800 2,700
Retainer Uniform One Sheet 900
(common to parents and children)
Uniform One Sheet 550
Thrust metal Uniform One Sheet 650
Connecting rod Uniform One 5,200 7,800
Crankshaft In-line 4-cylinder
One 37,700 55,250
Crankshaft In-line 6-cylinder
One 53,300 78,650
Oil pump gear Uniform One Car 8,000 WPC + tin combined processing
Piston Height↓ 50φ 60φ 70φ 80φ 90φ 100φ 110φ 120φ
50mm 2,600 3,120 3,640 4,160 4,420 4,940 5,460 5,980
60mm 3,120 3,640 4,160 4,940 5,460 5,980 6,500 7,280
70mm 3,640 4,160 4,940 5,720 6,240 7,020 7,800 8,320
80mm 4,160 4,940 5,720 6,500 7,280 8,060 8,840 9,620
90mm 4,420 5,460 6,240 7,280 8,060 8,840 9,880 10,660

For example, in the case of RB26 genuine piston ⌀86 x height 55.6, the piston table adapts to ⌀90 60mm and costs ¥ 6,006.

Cylinder block, cylinder head, camshaft, head (stud) bolt, connecting rod bolt, and other functional bolts, mission gear, synchro, shift forks, mission case, differential gear, pinion shaft. Please feel free to contact us regarding WPC processing such as drive shafts.

For WPC processing requests of 16,500 yen or less, a handling fee of 1,650 yen will be charged.

● “WPC” and “WPC processing” are registered trademarks of Fuji Machine Sales Co., Ltd. and Fuji Seisakusho Co., Ltd.