※Shandong Molong Petroleum Machinery Company Limited※

+	Sucker Rod
+	Sub Surface Sucker Rod pump
+	Pumping Unit
+	Reducer
+	Valve、Sleeve
+	Tubing and Casing
+	High Precision Steel Pipes
+	Special Seamless Steel Tube
+	Accessaries

·Products Display：High Precision Steel Pipes

We manufacture very high precision steel pipes mainly through cold drawing, cold rolling and galvanising to meet market demand. Our products feature benefits of high precision, stable quality and high price/performance ratios.

Our major products include:
1. A variety of standard and non-standard super high precision hydraulic and pneumatic cylinders:
Internal diameter: Φ30～Φ400mm Wall thickness: 2.5～25mm
Materials: 20#, 45#, 16Mn, 37Mn5, 27SiMn
Standards: GB8713-88 high-precision internally seamless steel pipes for hydraulic and pneumatic cylinders
GB3639-83 cold-drawn or cold-rolled high precision seamless steel pipes

1、Product types are as below:

Processing mode	Diameter (mm)	Length	Straightness (mm)	Precision level	Inside roughness (μm)
Cold-rolled	30—100	≤12m	0.3～1.0/1000	H8～H10	0.4～1.6
Cold-drawn	30—400	≤10m		H8～H10	0.8～1.6
Galvanised	32—500	≤12m		H8～H9	0.4～0.8

2、The mechanic features of our cold-drawn and cold-rolled high precision steel pipes are as below：

No.	Delivery condition
	Cold processing/hard (Y)		Cold processing/soft (R)		empering for Tension Relief (T)
	σ_b MPa	δ₅ %	σ_b MPa	δ₅ %	σ_b MPa	δ₅ %
10	420	6	380	10	340	12
20	520	5	460	8	440	10
30	600	4	560	6	530	8
45	660	4	640	5	620	7

3、Dimension tolerance of our cold-drawn and cold-rolled high precision steel pipes：

Internal diameter(mm)	Internal diameter tolerance(mm)			Wall thickness tolerance
Internal diameter(mm)	Upper toleranc H8 Lower tolerance	Upper toleranc H9 Lower tolerance	Upper toleranc H10 Lower tolerance	Wall thickness tolerance
30	+0.033 0	+0.052 0	+0.084 0	±5%
＞30—50	+0.039 0	+0.062 0	+0.100 0
＞50—80	+0.046 0	+0.074 0	+0.120 0
＞80—120	+0.054 0	+0.087 0	+0.140 0
＞120—180	+0.064 0	+0.100 0	+0.160 0
＞180—250	+0.072 0	+0.115 0	+0.185 0
＞250—315	+0.081 0	+0.130 0	+0.210 0
＞315—400	+0.089 0	+0.140 0	+0.230 0

The delivery specifications of our pipes for high precision steel pipes systems are as below：

Pump Specs	Performance standards	Materials	Internal circumference(mm)	Wall thickness tolerance(mm)	Roughness (μm)
					Internal surface	External surface
1 1/4″	API SPEC11AX	20/45	0.03	≤0.3	Ra≤0.4～1.6	Ra≤3.2
1 1/2″		20/45
1 3/4″		20/45
2 1/4″		20/45
2 3/4″		20/45	0.035
3 1/4″