Hydraulic Steel Tubes

HYDRAULIC STEEL TUBES

7. Hydraulic Tube (ST37.4 NBK) Working Pressure Table:

No.	Description	Working Pressure (Bar)	Burst Pressure (Bar)	IMPA CODE
1	4MM OD x 1.0MM THK x 6 MTR	707	1755	710701
2	5MM OD x 1.0MM THK x 6 MTR	565	1404	-
3	6MM OD x 1.0MM THK x 6 MTR	471	1170	710702
4	6MM OD x 1.5MM THK x 6 MTR	707	1755	710703
5	8MM OD x 1.0MM THK x 6 MTR	353	878	710704
6	8MM OD x 1.5MM THK x 6 MTR	530	1316	710705
7	8MM OD x 2.0MM THK x 6 MTR	707	1755	710706
8	8MM OD x 2.5MM THK x 6 MTR	883	2194	-
9	10MM OD x 1.0MM THK x 6 MTR	283	702	710707
10	10MM OD x 1.2MM THK x 6 MTR	339	845	710708
11	10MM OD x 1.5MM THK x 6 MTR	424	1053	710709
12	10MM OD x 2.0MM THK x 6 MTR	565	1404	710710
13	10MM OD x 2.5MM THK x 6 MTR	707	1755	-
14	12MM OD x 1.0MM THK x 6 MTR	236	585	710711
15	12MM OD x 1.2MM THK x 6 MTR	283	702	710712
16	12MM OD x 1.5MM THK x 6 MTR	353	878	710713
17	12MM OD x 2.0MM THK x 6 MTR	471	1170	710714
18	12MM OD x 2.5MM THK x 6 MTR	589	1463	-
19	12MM OD x 3.0MM THK x 6 MTR	707	1755	-
20	14MM OD x 1.5MM THK x 6 MTR	303	752	-
21	14MM OD x 2.0MM THK x 6 MTR	404	1003	-
22	14MM OD x 2.5MM THK x 6 MTR	505	1254	-
23	14MM OD x 3.0MM THK x 6 MTR	606	1504	-
24	14MM OD x 4.0MM THK x 6 MTR	807	2006	-
25	15MM OD x 1.0MM THK x 6 MTR	188	468	-
26	15MM OD x 1.2MM THK x 6 MTR	226	562	710715
27	15MM OD x 1.5MM THK x 6 MTR	283	702	710716
28	15MM OD x 2.0MM THK x 6 MTR	377	936	710717
29	15MM OD x 2.5MM THK x 6 MTR	471	1170	710718
30	15MM OD x 3.0MM THK x 6 MTR	565	1404	-
31	16MM OD x 1.5MM THK x 6 MTR	265	658	710719
32	16MM OD x 2.0MM THK x 6 MTR	353	878	710720
33	16MM OD x 3.0MM THK x 6 MTR	530	1316	-
34	18MM OD x 1.5MM THK x 6 MTR	236	585	710721
35	18MM OD x 2.0MM THK x 6 MTR	314	780	710722
36	18MM OD x 2.5MM THK x 6 MTR	393	975	710723
37	18MM OD x 3.0MM THK x 6 MTR	471	1170	-
38	20MM OD x 2.0MM THK x 6 MTR	283	702	710724
39	20MM OD x 2.5MM THK x 6 MTR	353	878	710725
40	20MM OD x 3.0MM THK x 6 MTR	424	1053	710726
41	20MM OD x 3.5MM THK x 6 MTR	495	1229	-
42	20MM OD x 4.0MM THK x 6 MTR	565	1404	-

No.	Description	Working Pressure (Bar)	Burst Pressure (Bar)	IMPA CODE
43	20MM OD x 4.5MM THK x 6 MTR	636	1580	-
44	20MM OD x 5.0MM THK x 6 MTR	707	1755	-
45	22MM OD x 2.0MM THK x 6 MTR	257	638	710727
46	22MM OD x 2.5MM THK x 6 MTR	321	798	-
47	22MM OD x 3.0MM THK x 6 MTR	385	957	710728
48	22MM OD x 4.0MM THK x 6 MTR	514	1276	-
49	25MM OD x 2.0MM THK x 6 MTR	226	562	710729
50	25MM OD x 2.5MM THK x 6 MTR	283	702	710730
51	25MM OD x 3.0MM THK x 6 MTR	339	842	710731
52	25MM OD x 3.5MM THK x 6 MTR	396	983	-
53	25MM OD x 4.0MM THK x 6 MTR	452	1123	-
54	25MM OD x 5.0MM THK x 6 MTR	565	1404	-
55	28MM OD x 2.0MM THK x 6 MTR	202	501	-
56	28MM OD x 2.5MM THK x 6 MTR	252	627	710732
57	28MM OD x 3.0MM THK x 6 MTR	303	752	-
58	28MM OD x 4.0MM THK x 3 MTR	404	1003	-
59	28MM OD x 5.0MM THK x 6 MTR	505	1254	-
60	30MM OD x 2.0MM THK x 6 MTR	188	468	-
61	30MM OD x 2.5MM THK x 6 MTR	236	585	710733
62	30MM OD x 3.0MM THK x 6 MTR	283	702	-
63	30MM OD x 4.0MM THK x 6 MTR	377	936	-
64	30MM OD x 5.0MM THK x 6 MTR	471	1170	-
65	35MM OD x 2.0MM THK x 6 MTR	161	401	-
66	35MM OD x 2.5MM THK x 6 MTR	202	501	710734
67	35MM OD x 3.0MM THK x 6 MTR	242	602	-
68	35MM OD x 4.0MM THK x 6 MTR	323	802	710735
69	35MM OD x 5.0MM THK x 6 MTR	404	1003	-
70	38MM OD x 3.0MM THK x 6 MTR	223	554	-
71	38MM OD x 4.0MM THK x 6 MTR	297	739	-
72	38MM OD x 5.0MM THK x 6 MTR	372	924	-
73	42MM OD x 2.0MM THK x 6 MTR	135	334	-
74	42MM OD x 3.0MM THK x 6 MTR	202	501	-
75	42MM OD x 4.0MM THK x 6 MTR	269	669	710736
76	42MM OD x 5.0MM THK x 6 MTR	336	836	-
77	50MM OD x 3.0MM THK x 6 MTR	170	421	-
78	50MM OD x 5.0MM THK x 6 MTR	283	702	-
79	60MM OD x 3.0MM THK x 6 MTR	141	351	-
80	60MM OD x 5.0MM THK x 6 MTR	236	585	-
81	65MM OD x 6.0MM THK x 6 MTR	261	648	-
82	75MM OD x 3.0MM THK x 6 MTR	113	281	-
83	1/8"NB x 2.41MM THK x 6 MTR	649	1611	-
84	1/4"NB x 3.02MM THK x 6 MTR	618	1536	-

No.	Description	Working Pressure (Bar)	Burst Pressure (Bar)	IMPA CODE
85	3/8"NB x 3.2MM THK x 6 MTR	523	1298	-
86	1/2"NB x 3.0MM THK x 6 MTR	391	971	-
87	3/4"NB x 3.0MM THK x 6 MTR	312	774	-
88	1"NB x 3.5MM THK x 6 MTR	291	723	-
89	1"NB x 4.55MM THK x 6 MTR	378	939	-
90	1 1/4"NB x 4.85MM THK x 6 MTR	321	797	-
91	1 1/2"NB x 5.08MM THK x 6 MTR	295	734	-
92	2 1/2"NB x 6.3MM THK x 6 MTR	NIL	580	-
93	1/4"OD x 1.2MM THK x 6 MTR	534	1327	-
94	1/4"OD x 1.5MM THK x 6 MTR	668	1658	-
95	3/8"OD x 1.22MM THK x 6 MTR	362	899	-
96	3/8"OD x 1.5MM THK x 6 MTR	445	1105	-
97	1/2"OD x 1.5MM THK x 6 MTR	334	829	-
98	3/4"OD x 2.0MM THK x 6 MTR	297	737	-
99	3/4"OD x 2.64MM THK x 6 MTR	392	973	-
100	1"OD x 3.0MM THK x 6 MTR	334	829	-
101	1 1/4"OD x 3.0MM THK x 6 MTR	267	663	-
102	1 1/4"OD x 3.25MM THK x 6 MTR	289	719	-

8. Hydraulic Tube (ST52.4 NBK) Working Pressure Table:

No.	Description	Working Pressure (Bar)	Burst Pressure (Bar)	IMPA CODE
103	10MM OD x 2.0MM THK x 6 MTR	799	1919	710710
104	12MM OD x 2.0MM THK x 6 MTR	666	1599	710714
105	14MM OD x 1.5MM THK x 6 MTR	428	1028	-
106	14MM OD x 2.0MM THK x 6 MTR	571	1371	-
107	15MM OD x 1.5MM THK x 6 MTR	400	959	710716
108	15MM OD x 2.0MM THK x 6 MTR	533	1279	710717
109	15MM OD x 2.5MM THK x 6 MTR	666	1599	710718
110	16MM OD x 1.5MM THK x 6 MTR	375	899	710719
111	16MM OD x 2.0MM THK x 6 MTR	500	1199	710720
112	16MM OD x 3.0MM THK x 6 MTR	749	1799	-
113	18MM OD x 1.5MM THK x 6 MTR	333	800	710721
114	18MM OD x 2.0MM THK x 6 MTR	444	1066	710722
115	20MM OD x 2.0MM THK x 6 MTR	400	959	710724
116	20MM OD x 2.5MM THK x 6 MTR	500	1199	710725
117	20MM OD x 3.0MM THK x 6 MTR	599	1439	710726
118	22MM OD x 2.0MM THK x 6 MTR	363	872	710727
119	25MM OD x 2.0MM THK x 6 MTR	320	768	710729
120	25MM OD x 2.5MM THK x 6 MTR	400	959	710730
121	25MM OD x 3.0MM THK x 6 MTR	480	1151	710731
122	25MM OD x 4.0MM THK x 6 MTR	639	1535	-
123	25MM OD x 5.0MM THK x 6 MTR	799	1919	-
124	28MM OD x 2.0MM THK x 6 MTR	285	685	-
125	28MM OD x 3.0MM THK x 6 MTR	428	1028	-
126	30MM OD x 2.0MM THK x 6 MTR	266	640	-
127	30MM OD x 3.0MM THK x 6 MTR	400	959	-
128	30MM OD x 4.0MM THK x 6 MTR	533	1279	-
129	35MM OD x 3.0MM THK x 6 MTR	343	822	-
130	35MM OD x 4.0MM THK x 6 MTR	457	1096	710735
131	38MM OD x 3.0MM THK x 6 MTR	315	757	-
132	38MM OD x 4.0MM THK x 6 MTR	421	1010	-
133	38MM OD x 5.0MM THK x 6 MTR	526	1262	-
134	42MM OD x 3.0MM THK x 6 MTR	285	685	-
135	42MM OD x 4.0MM THK x 6 MTR	381	914	710736
136	42MM OD x 5.0MM THK x 6 MTR	476	1142	-
137	45MM OD x 5.0MM THK x 6 MTR	444	1066	-
138	50MM OD x 5.0MM THK x 6 MTR	400	959	-
139	50MM OD x 6.0MM THK x 6 MTR	480	1151	-
140	50MM OD x 10.0MM THK x 6 MTR	799	1919	-
141	54MM OD x 6.0MM THK x 6 MTR	444	1066	-
142	60MM OD x 5.0MM THK x 6 MTR	333	800	-
143	60MM OD x 6.0MM THK x 6 MTR	400	959	-

No.	Description	Working Pressure (Bar)	Burst Pressure (Bar)	IMPA CODE
144	65MM OD x 8.0MM THK x 6 MTR	492	1181	-
145	66MM OD x 8.5MM THK x 6 MTR	515	1236	-
146	76.1MM OD x 6.3MM THK x 6 MTR	331	794	-
147	80MM OD x 10.0MM THK x 6 MTR	500	1199	-
148	90MM OD x 5.0MM THK x 6 MTR	222	533	-
149	90MM OD x 10.0MM THK x 6 MTR	444	1066	-
150	97MM OD x 12.0MM THK x 6 MTR	494	1187	-
151	100MM OD x 10.0MM THK x 6 MTR	400	959	-
152	115MM OD x 15.0MM THK x 6 MTR	521	1251	-
153	120MM OD x 12.0MM THK x 6 MTR	400	959	-
154	130MM OD x 15.0MM THK x 6 MTR	461	1107	-
155	150MM OD x 15.0MM THK x 6 MTR	400	959	-
156	190MM OD x 20.0MM THK x 6 MTR	421	1010	-
157	2"OD x 5.9MM THK x 6 MTR	464	1114	-
158	2"OD x 6.0MM THK x 6 MTR	472	1133	-

Material Specification	ST37.4 (E235) ST52.4 (E355)
Dimension Specification	DIN EN 10305-4 (DIN 2445/2) DIN EN 10305-1 (DIN 2391/C)
Outer Diameter Size	4 to 130mm external diameter
Finishing	Normalized / Phosphate (NBK)

Hydraulic steel tubes are a major component that allows free passage of fluids in pipes, valves, and other hydraulic machines. Hydraulic tubes are suitable for use in various hydraulic machines and require low maintenance. The tube is available in DIN 2445/2 (DIN EN 10305-4) or DIN 2391/C (DIN EN 10305-1) standards and measured in inches nominal bore size (NB) or outer diameter (OD) and millimeters (MM).

Produced with two different materials, E235 (ST 37.4) or E355 (ST 52.4), the synthetic elements help regulate pressure in the hydraulics. Without a change in the working pressure, the latter has an advantage of the increased mass and density depletion over the former.

1. What is Hydraulic system and how does it work?

With the invention of more machinery in the 18th century, hydraulic systems were built to replace a steam hammer. This further led to hydraulic systems being used in operating systems such as cranes, elevators, ports, steel production, etc. The hydraulic system was developed from Pascal's Law, a French mathematician, Blaise Pascal. The law states that an enclosed fluid can transmit pressure to all parts of the container without altering the weight. This propelled the research. This drove the research by Joseph Bramah to invent the hydraulic press (system) in 1795. Today, hydraulic systems are well-known and used by many construction companies, machinery, and automobiles.

Hydraulic tubes are cylindrically shaped tools found in hydraulic systems that aid liquids' flow to and from other components. The hydraulic system comprises several elements, with four classified as major parts: pump, reservoir, valve, and actuators. These components direct the storage of liquid, pressure application, conversion of energy, control, and fluids movement.

EN 10305-4 Hydraulic Steel Tubes

2. What is Hydraulic Tube?

DIN 2391C Hydraulic Steel Tubes

The Hydraulic tubes are finished through a cold drawn method, mostly used in shaping steel bars (stainless and carbon). This method gives the hydraulic tubes more straightness, strength, increased tolerance, and efficiency. Also, it has seamless precision, which makes it light weighted. These two qualities make the tubes suitable for use in all machines, including sophisticated ones.

In length, the tubes are 6 meters long. Purchasing the right tube size of hydraulic tubes is very important in achieving the optimum use and maintaining the system's efficiency. Failure to do this may result in damage to other parts and cavitation. The measurement of the inner and outer diameter is needed for determining the size of the tube. This is combined with the thickness of the wall. That is inner diameter + thickness of the wall or outer diameter + thickness of the wall.

The hydraulic tube is made up of two different materials – ST37.4 or ST52.4. ST37.4 tube has anti-rust quality, bright heat light, clean inner walls, pressure-resistant, and no oxidation.

The chemical composition for the ST37.4 material is as follows:

Material	Carbon	Silicon	Manganese	Phosphorus	Sulfur
ST 37.4	≤ 0.17%	≤ 0.35%	≤ 1.2%	≤ 0.0045	≤ 0.0045

The tensile strength for the product ranges between 340 N/mm2, and it has a minimum yield strength of 235MPa. A steel tube with an outer diameter of less than 30MM and thickness less than 3.0MM will result in tensile strength of 225MPa.

For the ST52.4 material, the chemical composition is shown in the table below:

Material	Carbon	Silicon	Manganese	Phosphorus	Sulfur
ST 52.4	≤ 0.17%	≤ 0.35%	≤ 1.2%	≤ 0.0045	≤ 0.0045

The tensile strength is higher than ST37.4, which ranges from 490N/mm2 to 630N/MM2. For yield strength, it has a minimum of 355MPa.

BAHASA INDONESIA

3. What is Hydraulic Tube?

Hydraulic tubes and hoses serve the same purpose in a hydraulic machine. However, it may not be easy to ascertain the best amongst these two materials.

Hydraulic Tubes

Ability to work and maintain shape under high heat

Less expensive and easily available for purchase

Highly durable

Description

Workability
and Expansion

Cost

Durability

Hydraulic Hose

Low-level of heat resistance. Tend to expand when the heat level is high.

Expensive

Has a limited time for use

These differences have made the hydraulic tubes more opted for when using hydraulic machines.

4. What is Hydraulic Tube made of?

Hydraulic Steel Tubes 6 Meters Long

While making a hydraulic tube, two methods can be used – welding or a seamless method. The welding process involves a combination of metal pieces using heat. This softens the metal and allows bending to the desired shape easily. The process has been long-existing and can be used in several ways.

The seamless method is used when a tube is connected to another without any trace of welding. This is possible because the tubes have a thread at the ends, which can be quickly joined to another through threading. A seamless pipe is more robust and lasts longer than welded tubes. Our tubes are made from the seamless method, making it more durable and able to withstand more pressure.

The tube surface is finished with NBK (normalized). With this method, the tubes are exposed to protective heat treatment in an oxidation-free area to achieve the tubes' shiny, smooth, and glossy surface area. The tube is also greased thoroughly internally and externally, and melted ions are left to cool down after heating naturally. This also gives the tubes an anti-rust property and enhances the strength of the tubes.

Galvanization of the tubes is also available. To increase the tubes' anti-rust quality, zinc is applied for an extra coating of the tube. There are several methods of galvanizing, however, the hot-dip method is mostly used. The Hot-dip galvanization method drops a thick size of the zinc on the melted tube, and this is applied before painting. The electro-galvanizing can be used when a lighter form of zinc is needed on the tube's surface.

5. What is the pressure rating for Hydraulic Tubing?

The pressure ratings are measured using as per DIN 2413 while working with moderate temperatures. Actual yield and tensile stress values can be found on certificates of the materials. However, the table on the right shows several temperatures for reduction of pressure:

Working pressure allowed in elevated temperature is calculated by rating factor thickness multiplied by working pressure allowed for the tube's outer diameter.

C (in degree)	F (in degree)	Rating Factor
40	-40	0.90
120	248	1.00
150	302	0.89
175	347	0.89
200	392	0.83
250	482	NA

6. How do you build a Hydraulic Line?

Setting up a hydraulic line can be done using simple steps. Materials to be used are wheel cutter, hydraulic tube bender, safety goggles, pipe clamp, lubricant, and gloves (optional).

Before the process begins, ensure you have the right size of the hydraulic tubes for your machine. Then, follow the following steps

Hydraulic Steel Tubes ST37.4

STEP 1
The first step is cutting the tubes. You have to cut the tubes to the desired length, and this can be done using a wheel cutter or an engine.

STEP 2
The next step is bending the hydraulic tube. You can bend the tube manually or make use of a hydraulic tube bender for this step.

STEP 3
After cutting, the next step is welding. Welding requires joining two metal materials with heat. The welding process is split into three stages – beveling, selecting the desired welding process, and checking for errors. The bevel process involves changing the structure of metals to be joined. This gives a stronger weld and reduces the probability of developing issues as time proceeds.

After this, you select the method of welding to use. Remember to use your safety goggles and gloves to avoid accidents.

After the process, check for loopholes or faulty areas before use.

STEP 4
The last way is the installation of the hydraulic line welded.