Welcome to Baoji Zhongpu Non-Ferrous Metals Co., Ltd.

Today Is:

Position:

Home >> NEWS >> FAQ


Determination and treatment of leakage in titanium heat exchanger

Titanium heat exchanger using time is long will gradually appear some problems, common problem is the equipment of leakage and leakage problems such as equipment, facing different problems need to adopt the right method to solve, to promotes the repair of equipment, small make up for everybody introduction now is titanium heat exchanger handling problems.

Leakage is sometimes found in the use of stainless steel spiral plate heat exchanger, usually in two forms, one is internal leakage, the other is external leakage.

1, equipment leakage, leakage is mainly the welding part of the main body, flange joint, pipe connection leakage. The most common corrosion parts are process nozzles, and then tube plate, big cover and small diameter nozzles, because the wall thickness of process nozzles is thinner than other parts, and the relative flow rate is higher than other parts.

2, equipment leakage

Internal leakage generally refers to pipe perforation and small floating head leakage, resulting in tube, shell side medium string. Pipe erosion, erosion, wear caused by thinning and perforation; Loose fastening bolts of floating head cover and deterioration of sealing gasket can cause leakage in heat exchanger. In the stainless steel plate heat exchanger after the maintenance of the pressure test seal gasket selection is not appropriate, and the device pneumatic condenser with steam blowing air tight loosening of the small floating head bolt caused internal leakage.

Determination and treatment of leakage in titanium/stainless steel spiral plate heat exchanger

Determination of internal leakage point

1.1 Drilling, mainly adopt the method of combining drilling with irrigation and pressure.

1.2 Pour water to check leaks

It is difficult to determine the leakage point when there is a series leakage in the channel. Ss-i spiral plate heat exchanger is composed of two closed and independent spiral channels in order to accurately detect the leakage point. The method of drilling holes was used. When drilling, the drilling position should be fixed on the same spiral channel at one end of the heat exchanger, and arranged in a cross shape. When drilling, it should also try to ensure that iron filings do not fall into the heat exchanger, so as to make the channel smooth.

2 repair of internal leakage

2.1 digging a hole

A pressure pump is used to fill water into the heat exchanger on a channel that has not been drilled. And form a certain pressure, then heat exchanger series of leakage location will be running water, flow to another channel (drilled channels), and from the nearest funnelled layer drilling drop down, then drilled at one end of the heat exchanger should be placed upside down), by the location of the drops of water, can determine which layer of the internal leakage, at this point to the same heat exchanger layer did not cut a hole on one side of the head Section as the observation hole, from the observation hole can accurately determine the specific leakage point.

2.2 slag removal

From the most outer layer of the heat exchanger corresponding to the leak point, to determine the position of the leak point. Start cutting holes, the order is from the outside to the inside, until the layer with the leak point. The hole cut should be oval, and the size of the outer layer is large, gradually small to the inside, generally each layer of the hole size difference of 40mm, such as the leak point is deep, the outer hole cut should be larger.

2.3 Installing a repairing board

The oxide slag should be cleaned carefully on each layer of the board, after cutting the hole. This is the key to welding back filling plate, back filling plate and each layer of spiral plate can be welded tight, available chisel and dressing mold grinding wheel cleaning oxide slag, Yantai side special chemical remind you: pay attention to clean the residue, don let it fall into the heat exchanger.

2.4 Internal leakage point and repair plate

Sheet material cut from each layer of heat exchanger to ensure the quality of repair. It is no longer used, and it should be re-matched with the filling plate. The filling plate should use the same data and thickness as the spiral plate of heat exchanger, and its periphery should be 15mm20mm larger than the hole cut by each layer of heat exchanger, and it should also be oval, and made into an arc consistent with the radian of each layer of titanium stainless steel spiral plate heat exchanger.

It is necessary to use hand grinding wheel to clean the leak, and carefully check the leak point is a crack or trachoma. Grind out grooves to ensure welding quality. The diameter of electrode is 3.2mm, and J422 electrode is used for welding repair. The current is controlled between 100-120A [1]. The leakage point is welded first and then the repair plate of each layer is welded successively from inside to outside. Its purpose is easy to operate, the elliptic patch plate is close to the inner arc surface of the heat exchanger for welding. To ensure the welding quality, a section of round steel can be welded on the patch plate, so that the oval patch plate can be installed into the heat exchanger smoothly. After spot welding the oval patch plate, remove it.

It is mainly to increase the mutual stiffness of the oval repair plates.) The number of short round steel braces welded on each layer of the repair plates is determined by the size of the repair plates. 5. Generally, 23 are welded on the outer and slightly larger layers of the filling plate, and 12 are welded on the inner layer of the filling plate. Therefore, the original cut steel plate can be directly installed in the original position of the alignment welding. During welding, the outermost steel plate should be δ12mm thick. After welding each layer of oval repair plate, carefully check the welding position, if there is trachoma to repair welding, to ensure the welding quality of each layer.

Pressure test and plug drilling hole

Use the pressure pump to fill water into the channel that is not drilled through the hole. After welding the internal leakage point and the filling plate. And formed 0.51.0mpa pressure, and adhere to a certain time, should not appear pressure relief phenomenon. Sealing drilled holes: used to drill the short round steel section with the same diameter, sealing and welding the position of drilled holes and observation holes, and then carry out water pressure test on the channel, the pressure is 0.51.0mpa, should not leak.

The pressure test process must pay attention to :1 to the heat exchanger before cutting holes, to steam the residual chemical substances in the heat exchanger blowing clean, so as not to produce combustion when gas cutting, accidents. Before repairing titanium stainless steel spiral plate heat exchanger, it should be confirmed whether the corrosion is serious, and it is necessary to determine whether there is any repair.