How To Distinguish Good And Bad Of Steel Pipe Fittings?

Jun. 01, 2023

How To Distinguish Good And Bad Of Steel Pipe Fittings?

The main materials of malleable iron pipe fittings are: white heart malleable iron, black heart malleable iron, Pearlized malleable iron, JIANZHI fittings main material used in building support fittings is black malleable cast iron, which has good hardness and high plasticity and toughness. Most of the global malleable iron fittings manufacturers use black malleable cast iron as the raw Material of steel pipe fittings, only a small part of European businesses use white malleable cast iron as the Raw Material of steel pipe fittings.

1.Malleable Iron Applications

Malleable iron pipe fittings are mainly used in water systems, petrochemical systems, gas systems, plumbing systems, and plastic-lined fittings for building support fittings can be used in drinking water systems. Problems with any of the above mentioned systems are not only economic losses, but also threaten life safety. So how do we buy safe and reliable malleable iron pipe fittings?

2.How To Identify Of Malleable Iron Pipe Fittings.

Here is a way to identify of malleable iron pipe fittings. it help you improve the ability to identify the malleable iron pipe fittings, to be able to choose more high-quality pipe fittings.the way provide protection for everyone.

3.Learn About The Manufacturer's Products

First of all, understand the manufacturer of malleable iron pipe fittings products, each manufacturer in the introduction and explain the parameters of pipe fittings, such as JIANZHI pipe fittings temperature of 200 degrees Celsius, working pressure 1.6mpa, tensile strength greater than 330mpa, elongation greater than 8%, hardness less than 150hb. collect the data of several malleable iron pipe fittings manufacturers. Select the most suitable vendor to purchase.

jianzhi galvanized malleable iron pipe fittings.png 

 jianzhi galvanized malleable iron pipe fittings


4.Understanding From The Outside

The second from the appearance of the pipe fitting parts to distinguish good from bad, through first knock, second look, third weighing, the three steps to form a self-judgment of the  pipe fittings . the detailed description of next step.

5.First Knock

first knock: black heart malleable iron pipe fittings products have good toughness, after knocking the surface will leave dents or slight deformation, but the pipe will not produce cracks. This means that the quality of this product is over.

6.Second Look

Second look: look at the length of the thread, China's national standard is 1 inch vertebral pipe minimum length of internal threads can not be less than 11.6mm, external thread length of not less than 14.5mm, JIANZHI pipe fittings not only meet the standard but also provide NPT, PT, G, three thread standards for your choice. See if the surface of the pipe fittings are galvanized, galvanized in two ways: hot-dip galvanized and cold-dip galvanized. Hot-dip galvanizing is the process of heating zinc ingots to dissolve and then attaching a zinc film to the surface by hot dipping, which isolates the zinc layer from oxygen and prevents rust from oxidation. The advantage of hot-dip galvanizing is that the coating is thick and has a long life. Cold galvanizing is a process in which the product is electrolytically coated with zinc ions by the action of electrodes. The disadvantage is that the plating is thin, and the plating on the inner layer of the pipe fittings will be even thinner.

7.Three Weighing

Three weighing: jerry-built steel products will certainly reduce the outer diameter, thin wall thickness, shorten the middle and long dimensions, it is generally more than 10% less than the weight of fittings in line with national standards. We can identify the good and bad with the way of weighing.

If you have a better and more intuitive way to identify the good and bad of malleable iron fittings products. You can leave  message to discuss with us. We will accept good methods and will give you a small gift.



jianzhiI elbow product description.png

jianzhiI elbow product description



Of course, you can also click the link below to enter our YouTube , there are more wonderful videos. You can have a more intuitive understanding of the pipe fittings by JIANZHI Group.



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