Quality on piston rods means meeting the expectation of the customer, in the case of Kotec Hydraulic the highest known demand in the market was taken as standard and consequently the following criteria were examined:
1. Raw material supply
2. Bright bar production
3. Preparation prior to plating
4. Plating technology
5. Quality inspection
6. Packing
7. Customizing

RAW MATERIAL SUPPLY
At present steel grades for piston rods consist of carbon steels, micro alloyed steels, alloyed steels and stainless steels in order to cover all variations of hydraulic applications.
The steels should be free from macro nonmetallic inclusions and steel mills have been selected according this demand for clean steel as well as the possibilities to produce all grades, the possibilities to provide the required heat treatments and the capacity to produce the required volumes; Raw material receive an incoming control to check order conformance and bundles are labeled with bar code.

Steel Grade

NORMAL STEEL GRADE	Y.S.	T.S.	E.l.	HARDNESS
	PSI min	PSI min	% min	HB min
CK45	50,000	105,000	19	165-220
20MnV6	75,000	110,000	12	200-240
38MnVS6	85,000	123,500	14	250-300
42CrMo4 (Q&T)	100,000	135,000	12	265-320

MICRO-ALLOY STEEL GRADE	Y.S.	T.S.	E.L.	HARDNESS
	PSI min	PSI min	% min	HB min
HY4520	75,000	108,750	17	230-290
HY4700	87,000	130,000	16	270-340

Delivery Technical Conditions
CHROME THICKNESS : 20 to 30 micron
SURFACE ROUGHNESS: Ra≤0.2 micron and Rt≤2 micro
TOLERANCES ON DIA : ISO f7 on the diameter
OVALITY : Half of the tolerance ISO f7
STRAIGHTNESS : ≤0.2MM/M
SURFACE HARDNESS : 850-1150HV (vickers 100g)
POROSITY: Test according to ISO 1456/1458 and result evaluation according to ISO 10289 rating 8-10. when the plated surface is checked using 10 X lens, there shall not be more than 30 micro white pin-holes in every 1000mm2 area of plated surface. Further, the diameter of these micro pin-holes shall not be greater than 0.1mm approximately
CORROSION RESISTANCE: Test in natural salt spray according to ISO 9227/ASTM B117-120hours; Results evaluation according to ISO 10289 Rating 9.5.

Quality Assurance
In callobration with Italian experts in this industry, the chrome surface consists mutiple layer through a chrome continous plating line. It's called " Multi-Layer Chrome Plating Technology" which grants a perfect barrier between the base steel and external agents such as water, humidity, acid, corrosive moisture penetrating through the porous and uneven chrome surface and will initiate the corrosion.