5 Ways To Repair Diesel Generator Cylinder Block And Cylinder Head Cracks

The diesel generator cylinder and cylinder head should be repaired according to the degree of rupture of the diesel generator cylinder and the cylinder head. The repair method should be determined according to the degree of damage, the location of the damage, the situation of the work unit and the state of the equipment. The commonly used repair method is epoxy resin. Adhesive bonding, screw repair, patch repair, welding repair, leakage plugging agent, five methods.

1. Epoxy adhesive bonding.

Epoxy bonding has the advantages of strong adhesion, small shrinkage, fatigue resistance, etc. At the same time, the process is simple, the operation is convenient, and the cost is low. Its biggest disadvantage is heat resistance, impact resistance, etc., and in the next maintenance, the peeling phenomenon will occur after boiling with hot alkaline water, and it needs to be re-bonded. Therefore, this method can be used to repair other parts of the cylinder block and cylinder head, such as the combustion chamber, valve seat and other places with high temperature.

2. Screw filling.

This method is suitable for some flat parts with low requirements for force and low requirements for cracks (generally below 50mm), and its repair quality is better, but it is time-consuming. The special filling method is as follows.

(1) In order to prevent the crack from continuing to expand, drill a limit hole at each end of the crack.

(2) Crack drilling 3.4.5, the hole diameter depends on the thread diameter, and ensure that there is a 1/3 hole diameter overlap between the holes (for example: the 3rd hole and the 6.7 hole should overlap every 1/3 hole diameter).

(3) Thread the hole 1.2.3.4.5 above.

(4) During tapping, screw in the copper rod with pre-hinged thread (paint the part painted with white paint), and cut off the copper rod after tightening, so that the fracture is 1-1.5mm higher than the crack surface.

(5) Drill holes 6.7.8.9 between the screws have been cut off, tap and screw in the screws according to the above method, so that they are filled with cracks and form a helical chain.

(6) Press the filler tightly, tap between the cut screws with a hand hammer, and finally smooth it out with a file, and if necessary, solder it to prevent leakage.

3. Patching plate sealing method.

cylinder block. If the cylinder head is under less stress, if the crack is long or there is a hole, it should be sealed with a patch around the broken part.

(1) Each fracture end is drilled to limit propagation.

(2) Cut a 3~5mm thick copper sheet or a 1.5-2mm thick iron sheet into a patch panel similar to the profile of the break, and the surrounding size is greater than 15~20mm. If the fractured surface has raised portions, the same raised shape must be tapped on the patch so that the entire patch fits over the sealing surface.

(3) Every 10-15mm around the patch, drill holes with a diameter of 4-6mm, about 10mm from the edge of the patch.

(4) Press the patch plate on the break, use a scribe to mark the hole on the cylinder from the patch hole, remove the patch plate, drill a hole with a depth of about 10mm in the mark, and then tap out the hole. Thread diameter required.

(5) Fill asbestos lining coated with white paint between the cylinder body and the supplementary plate, and then fasten the supplementary plate in the cylinder with flat head bolts. If necessary, tap the supplemental plate with a small hammer and tighten the bolts to increase the seal.

4. Welding repair method.

When cracks occur, welding is often used to repair areas that are subject to high stress or temperature, and areas that are difficult to work with using the above methods. Its welding process is as follows:

(1) To prevent crack propagation, drill 3-5 mm holes at both ends.

(2) In special cases, chisel the cracks into V-shaped grooves of 60 degrees to 90 degrees, and clean them to make them bright.

(3) When using electric welding, DC welding should be used. When using acetylene to blanch, the cylinder or cylinder head should be slowly preheated, the welding area should be slowly preheated to about 500 °C, and then heated to 500~550 °C after welding repair. Keep for another 1h, and then slowly cool to room temperature for not less than 16h.

5. Blocking method of blocking agent.

Generally speaking, the colloidal liquid composed of water glass, inorganic coagulant, organic flocculant, inorganic filler and binder is suitable for blocking defects such as small cracks and blisters in cast iron or aluminum cylinders.

When using a leak-stopping agent to repair cracks, you should first find the location of the leak, and determine the length, width, and aperture of the crack. When the crack length exceeds 40~50mm, limit holes of 3~4mm can be drilled at both ends, and then spot welding or tapping is performed to prevent the crack from expanding. At the same time, drill holes every 30~40mm (do not drill holes) for spot welding or tighten the screws with tapping to avoid expansion cracks due to vibration. Such as the crack width. When the diameter of the sand hole exceeds 0.3mm, it is best not to repair in this way. The plugging agent is only suitable for small cracks or micro-leakage.

In addition, it should be emphasized that if there are cracks in key parts, such as cylinder holes, main bearing seats and other parts that are subjected to large forces, they generally cannot be repaired, and the cylinder block or cylinder head should be replaced. Special attention should be paid to the hydraulic test of the cylinder and cylinder head after repair to confirm whether there is any leakage.

Guangxi Dingbo Power Equipment Manufacturing Co., Ltd. is a manufacturer of professional generators, diesel generator sets, non-moving generator sets, Cummins generator sets, Volvo generator sets, etc. It has service departments across the country, providing users with design, supply, debugging, and maintenance at any time. Welcome customers to come to consult and visit. Looking forward to your inquiry, please send email to us for details sales@dieselgeneratortech.com