A stern shaft seal pressure oil test method

Abstract

The application discloses a stern shaft sealing oil pressure test method, which comprises the following steps: using a stern shaft lubricating oil gravity tank to press oil into a lubricating oil cavity of a stern shaft to check and confirm that a ⅢS number sealing ring of a rear sealing of the stern shaft and a Ⅳ number sealing ring of a front sealing of the stern shaft are free of lubricating oil leakage; using a rear sealing oil tank to press oil into a high-pressure lubricating oil cavity of the rear sealing to check and confirm that a Ⅲ number sealing ring of the rear sealing of the stern shaft is free of lubricating oil leakage; further pressing oil into an air cavity of the rear sealing to check and confirm that a Ⅰ number sealing ring and a Ⅱ number sealing ring of the rear sealing of the stern shaft are free of lubricating oil leakage; and using a front sealing oil tank to press oil into a low-pressure lubricating oil cavity of the front sealing to check and confirm that an outer part of the front sealing and a gap between the front sealing and the stern shaft are free of lubricating oil leakage. The application can effectively seal the lubricating oil in the bearing interval and prevent the lubricating oil from leaking outside the hull and the cabin, improves the sealing oil pressure efficiency, guarantees the sealing oil pressure effect, and avoids the problems of increased oil consumption, poor lubrication and water pollution caused by oil leakage.

Description

Technical Field

[0001] This invention relates to the field of shipbuilding technology, and in particular to a method for testing the pressure oil of a stern shaft seal. Background Technology

[0002] In ships that use propeller propulsion, a certain clearance must be left between the stern shaft and the stern bearing. The stern shaft is below the water surface and requires lubrication and cooling during operation. In order to prevent the lubricating oil in the stern shaft tube from leaking into the engine room and outside the ship, and at the same time to prevent seawater from flowing into the ship along the propeller, a stern sealing device needs to be installed on the ship.

[0003] Ship stern seals are divided into two parts: the front seal and the rear seal. The front seal is installed on the front end of the stern tube to prevent lubricating oil in the stern tube from leaking into the engine room. The rear seal is installed on the rear end of the stern tube to prevent lubricating oil in the stern tube from leaking outside the ship and to prevent water from outside the ship from entering the stern tube.

[0004] The front seal has two sealing rings (numbered IV and V), and the rear seal has four sealing rings (numbered I, II, III, and IIIS). The space between sealing rings I and II is the atmospheric pressure chamber, the space between sealing rings II and III is the air chamber, the space between sealing rings III and IIIS is the high-pressure lubricating oil chamber, the space between sealing rings IIIS and IV is the stern tube large chamber, and the space between sealing rings IV and V is the low-pressure lubricating oil chamber.

[0005] The stern shaft sealing device operates in extremely harsh environments and conditions. Besides wear from shaft rotation, it is also affected by uneven forces generated by the natural sinking of the shaft. Furthermore, the stern shaft experiences lateral and axial vibrations during engine reversing, all of which negatively impact the sealing device. Oil sealing is a commonly used stern shaft sealing method with the following advantages: 1. The stern shaft bearing uses oil-lubricated white alloy bearings. Due to the high load-bearing capacity of the oil film and its excellent lubrication performance, the sealing device effectively seals against seawater and sediment, preventing them from entering the stern tube. The white alloy bearings also experience minimal wear, resulting in relatively stable and reliable operation of the engine and shaft system. 2. The sealing device has excellent tracking performance, maintaining consistent sealing even during stern shaft sinking, radial runout, eccentric rotation, or axial movement. 3. It experiences less wear, lower frictional power, and less shaft power loss. 4. It has a long service life. However, ensuring that the lubricating oil can be effectively sealed within the bearing area without leaking to the outside and engine room has always been a problem that needs to be solved in oil lubrication sealing. Oil leakage not only increases oil consumption and causes poor lubrication, but also pollutes the water surface. Summary of the Invention

[0006] In view of this, the present invention provides a method for sealing oil pressure test of stern shaft, which can effectively seal the lubricating oil in the bearing area without leaking to the outside of the ship and the engine room, improve the efficiency of sealing oil pressure test, ensure the effect of sealing oil pressure test, and avoid problems such as increased oil consumption, poor lubrication, and water pollution caused by oil leakage.

[0007] A method for testing stern shaft seal oil pressure includes the following steps:

[0008] Stern shaft lubrication chamber oil pressure:

[0009] Oil was pressurized into the lubrication chamber of the stern shaft using a gravity oil pressurizer to check and confirm that there was no oil leakage in the No. IIIS sealing ring of the stern shaft rear seal and the No. IV sealing ring of the stern shaft front seal.

[0010] Stern shaft rear seal hydraulic pressure:

[0011] Pressurize the oil in the high-pressure lubricating oil chamber of the rear seal using the rear seal oil tank to check and confirm that there is no lubricating oil leakage in the No. 3 sealing ring of the stern shaft rear seal;

[0012] Then, pressurize the air cavity of the rear seal with oil using the rear seal oil tank to check and confirm that there is no oil leakage between the No. I and No. II sealing rings of the stern shaft rear seal;

[0013] Stern shaft front seal hydraulic oil:

[0014] Pressurize the oil in the low-pressure lubricating oil chamber of the front seal using the front seal oil tank to check and confirm that there is no lubricating oil leakage outside the front seal and between the front seal and the stern shaft.

[0015] Preferably, the specific steps for pressing oil into the stern shaft lubrication chamber are as follows:

[0016] First, add oil to the stern shaft oil gravity chamber and check for leaks in the connecting piping system between the stern shaft oil gravity chamber and the stern shaft.

[0017] After 15-30 minutes, open the outlet valve of the stern shaft lubricating oil gravity chamber and the inlet / outlet valve of the lubricating oil chamber to pressurize oil into the lubricating oil chamber. At the same time, continue to add oil to the stern shaft lubricating oil gravity chamber. When the oil volume in the stern shaft lubricating oil gravity chamber reaches the set value, open the stopcock on the high-pressure lubricating oil chamber with the rear seal and the stopcock on the low-pressure lubricating oil chamber with the front seal.

[0018] After 30-45 minutes, check and confirm that there is no oil leakage in the No. IIIS sealing ring of the stern shaft rear seal and the No. IV sealing ring of the stern shaft front seal, and the oil pressure in the shaft lubrication chamber is completed.

[0019] Preferably, when pressurizing the stern shaft rear seal with oil, the specific steps for pressurizing oil into the high-pressure lubricating oil chamber of the rear seal using the rear seal oil tank to check and confirm that there is no lubricating oil leakage in the No. III sealing ring of the stern shaft rear seal are as follows:

[0020] First, add oil to the rear sealing oil tank and check for leaks in the connecting pipe system between the rear sealing oil tank and the stern shaft.

[0021] After 15-30 minutes, open the valve on the first rear sealing oil pipe and pressurize oil into the high-pressure lubricating oil chamber between the No. Ⅲ and No. ⅢS sealing rings of the stern shaft rear seal. At the same time, open the stopcock at the top of the high-pressure lubricating oil chamber. When oil overflows from the top of the high-pressure lubricating oil chamber, tighten the stopcock again.

[0022] When oil is pressed into the high-pressure lubricating oil chamber, the oil level in the rear seal oil tank drops. After the oil level stabilizes, continue to add oil to the rear seal oil tank. When the oil level in the rear seal oil tank reaches the set value, open the stopcock on the air chamber between the No. II and No. III sealing rings of the stern shaft rear seal.

[0023] After 30-45 minutes, check and confirm that there is no oil leakage from the No. 3 sealing ring of the stern shaft rear seal.

[0024] Preferably, when pressurizing the stern shaft rear seal with oil, the specific steps for using the rear seal oil tank to pressurize oil into the air cavity of the rear seal to check and confirm that there is no lubricating oil leakage between the No. I and No. II sealing rings of the stern shaft rear seal are as follows:

[0025] Open the valve on the second rear sealing oil pipe to pressurize oil into the air cavity between sealing rings II and III, and at the same time open the stopcock at the top of the air cavity. When oil overflows from the top of the air cavity, tighten the stopcock again.

[0026] When oil is pressurized into the air chamber, the oil level in the rear seal oil tank drops. After the oil level stabilizes, continue to add oil to the rear seal oil tank. When the oil level in the rear seal oil tank reaches the set value, open the stopcock on the atmospheric pressure chamber between the No. I and No. II sealing rings of the stern shaft rear seal. When oil overflows from the top of the atmospheric pressure chamber, tighten the stopcock again and check to confirm that there is no lubricating oil leakage between the No. I and No. II sealing rings of the stern shaft rear seal.

[0027] Preferably, the specific steps for pressurizing the stern shaft front seal with oil are as follows:

[0028] First, add oil to the front seal oil tank. After the oil level in the front seal oil tank reaches the set value, open the stopcock on the low-pressure lubricating oil chamber between the No. IV and No. V sealing rings of the front seal. When oil overflows from the top of the low-pressure lubricating oil chamber, tighten the stopcock again.

[0029] After 30-45 minutes, check to confirm that there is no oil leakage from the outside of the front seal and the gap between the front seal and the stern shaft.

[0030] Preferably, a small amount of lubricating oil leakage is allowed when the stern shaft lubricating oil chamber is pressurized, the stern shaft rear seal is pressurized, and the stern shaft rear front seal is pressurized. The maximum allowable leakage amount of lubricating oil is no more than 0.5 liters / 3 hours.

[0031] The beneficial effects of this invention are:

[0032] This invention can effectively seal the lubricating oil within the bearing area without leaking to the outside of the ship and the engine room, thereby improving the efficiency of sealing and pressing oil, ensuring the effectiveness of sealing and pressing oil, and avoiding problems such as increased oil consumption, poor lubrication, and water pollution caused by oil leakage. Attached Figure Description

[0033] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0034] Figure 1 This is a schematic diagram of the piping connections between the stern shaft and the stern shaft lubricating oil gravity tank, the aft sealing oil tank, and the front sealing oil tank.

[0035] Figure 2 This is a schematic diagram of the stern tube rear seal.

[0036] Figure 3 This is a schematic diagram of the stern tube front seal.

[0037] The labels in the diagram mean:

[0038] 1 is the stern shaft, 2 is the stern shaft lubricating oil gravity tank, 3 is the aft sealing oil tank, 4 is the forward sealing oil tank, 5 is the stern tube lubricating oil circulation tank, 6 is the first aft sealing oil pipe, 7 is the second aft sealing oil pipe, 8 is the propeller, 9 is the aft stern tube, 10 is the forward stern tube, and 11 is the propeller shaft. Detailed Implementation

[0039] To better understand the technical solution of the present invention, the embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0040] It should be understood that the described embodiments are merely some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0041] It should be understood that although the terms first, second, third, etc., may be used in this disclosure to describe various information, such information should not be limited to these terms, which are only used to distinguish information of the same type from one another. For example, without departing from the scope of this disclosure, first information may also be referred to as second information, and similarly, second information may also be referred to as first information. Depending on the context, the word "if" as used herein may be interpreted as "when," "when," or "in response to determination."

[0042] The present application will now be described in further detail with reference to specific embodiments and accompanying drawings.

[0043] This invention provides a method for testing the pressure oil of a stern shaft seal. Figure 2 This is a schematic diagram of the stern tube aft seal, which is equipped with four sealing rings: No. I sealing ring, No. II sealing ring, No. III sealing ring, and No. IIIS sealing ring. Figure 3 This is a schematic diagram of the stern tube forward seal. The forward seal has two sealing rings, namely sealing ring IV and sealing ring V. The space between sealing rings I and II is the atmospheric pressure chamber, the space between sealing rings II and III is the air chamber, the space between sealing rings III and IIIS is the high-pressure lubricating oil chamber, the space between sealing rings IIIS and IV is the stern tube main chamber, and the space between sealing rings IV and V is the low-pressure lubricating oil chamber.

[0044] The stern shaft seal oil pressure test method provided by the present invention specifically includes the following steps: oil pressure test of the stern shaft lubrication oil chamber, oil pressure test of the stern shaft rear seal, and oil pressure test of the stern shaft front seal.

[0045] When pressurizing the stern shaft lubrication chamber, the stern shaft lubrication gravity chamber 2 is used to pressurize the lubrication chamber of the stern shaft 1 to check and confirm that there is no lubrication leakage in the No. IIIS sealing ring of the stern shaft rear seal and the No. IV sealing ring of the stern shaft front seal.

[0046] Specifically, the steps for pressing oil into the stern shaft lubrication chamber are as follows:

[0047] First, add oil to the stern shaft lubricating oil gravity tank 2 and check whether the connecting pipe system between the stern shaft lubricating oil gravity tank 2 and the stern shaft 1 is leaking.

[0048] After 15-30 minutes (preferably 10-20 minutes), open the outlet valve of the stern shaft lubricating oil gravity tank 2. Figure 1 The shut-off valve ① and the inlet / outlet valve of the lubricating oil chamber ( Figure 1 The three-way valve (④) presses oil into the lubricating oil chamber and simultaneously continues to add oil to the stern shaft lubricating oil gravity tank 2. When the oil volume in the stern shaft lubricating oil gravity tank 2 reaches the set value, the stopcock on the high-pressure lubricating oil chamber with the rear seal and the stopcock on the low-pressure lubricating oil chamber with the front seal are opened.

[0049] After 30-45 minutes (preferably 30 minutes), check and confirm that there is no oil leakage in the No. IIIS sealing ring of the stern shaft rear seal and the No. IV sealing ring of the stern shaft front seal, and the oil pressure in the shaft lubrication chamber is finished.

[0050] When pressurizing the stern shaft rear seal with oil, first pressurize the oil in the high-pressure lubricating oil chamber of the rear seal using the rear seal oil tank 3 to check and confirm that there is no lubricating oil leakage in the No. 3 sealing ring of the stern shaft rear seal; then pressurize the oil in the air chamber of the rear seal using the rear seal oil tank 3 to check and confirm that there is no lubricating oil leakage in the No. 1 and No. 2 sealing rings of the stern shaft rear seal.

[0051] Specifically, the steps for pressurizing the stern shaft rear seal with oil are as follows:

[0052] First, add oil to the rear sealing oil tank 3 and check whether the connecting pipe system between the rear sealing oil tank 3 and the stern shaft 1 is leaking.

[0053] After 15-30 minutes (preferably 10-20 minutes), open the valve on the first rear sealing oil pipe 6. Figure 1 The shut-off valve ③ in the middle presses oil into the high-pressure lubricating oil chamber between the No. Ⅲ and No. ⅢS sealing rings at the rear of the stern shaft, and at the same time opens the plug at the top of the high-pressure lubricating oil chamber. When oil overflows from the top of the high-pressure lubricating oil chamber, tighten the plug again.

[0054] When oil is pressed into the high-pressure lubricating oil chamber, the oil level in the rear sealing oil tank 3 drops. After the oil level stabilizes, continue to add oil to the rear sealing oil tank 3. When the oil level in the rear sealing oil tank 3 reaches the set value, open the stopcock on the air chamber between the No. II and No. III sealing rings of the stern shaft rear seal.

[0055] After 30-45 minutes (preferably 30 minutes), check and confirm that there is no oil leakage from the No. 3 sealing ring of the stern shaft rear seal;

[0056] Then, open the valve on the second rear sealing oil pipe 7. Figure 1 Use the shut-off valve ②) to press oil into the air chamber between sealing rings II and III, and at the same time open the stopcock at the top of the air chamber. When oil overflows from the top of the air chamber, tighten the stopcock again.

[0057] When oil is pressurized into the air chamber, the oil level in the rear sealing oil tank 3 drops. After the oil level stabilizes, continue to add oil to the rear sealing oil tank 3. When the oil level in the rear sealing oil tank 3 reaches the set value, open the stopcock on the atmospheric pressure chamber between the No. I and No. II sealing rings of the stern shaft rear seal. When oil overflows from the top of the atmospheric pressure chamber, tighten the stopcock again and check to confirm that there is no lubricating oil leakage between the No. I and No. II sealing rings of the stern shaft rear seal.

[0058] When pressurizing the front seal of the stern shaft, pressurize the oil in the low-pressure lubricating oil chamber of the front seal using the front seal oil tank 4 to check and confirm that there is no lubricating oil leakage outside the front seal and between the front seal and the stern shaft.

[0059] Specifically, the steps for pressurizing the stern shaft front seal with oil are as follows:

[0060] First, add oil to the front seal oil tank 4. After the oil level in the front seal oil tank 4 reaches the set value, open the stopcock on the low-pressure lubricating oil chamber between the No. IV and No. V sealing rings of the front seal. When oil overflows from the top of the low-pressure lubricating oil chamber, tighten the stopcock again.

[0061] After 30-45 minutes (preferably 30 minutes), check to confirm that there is no oil leakage from the outside of the front seal and the gap between the front seal and the stern shaft.

[0062] In this embodiment, a small amount of lubricating oil leakage is allowed when the stern shaft lubrication oil chamber is pressurized, the stern shaft rear seal is pressurized, and the stern shaft rear front seal is pressurized. The maximum allowable amount of lubricating oil leakage is no more than 0.5 liters / 3 hours.

[0063] There is no requirement for the order of pressing the stern shaft lubricating oil chamber, pressing the stern shaft rear seal, and pressing the stern shaft rear front seal. As long as there is no oil leakage from the corresponding sealing ring after each pressing is completed, the requirements are met.

[0064] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A stern shaft seal pressure oil test method characterized by, Specifically comprising the following steps: Rudder lubricating oil cavity pressure oil: The stern shaft lubricating oil gravity tank is used to pressurize the lubricating oil cavity of the stern shaft to check and confirm that the ⅢS seal ring of the stern shaft rear seal and the Ⅳ seal ring of the stern shaft front seal have no oil leakage. The specific steps of the stern shaft lubricating oil cavity pressure oil are as follows: First, add oil to the stern shaft lubricating oil gravity tank, and check whether the connecting pipeline between the stern shaft lubricating oil gravity tank and the stern shaft leaks. After 15-30 minutes, open the outlet valve of the stern shaft lubricating oil gravity tank and the inlet / outlet valve of the lubricating oil cavity, pressurize the lubricating oil cavity, and continue to add oil to the stern shaft lubricating oil gravity tank at the same time. When the oil amount in the stern shaft lubricating oil gravity tank reaches the set value, open the plug on the high-pressure lubricating oil cavity of the rear seal and the plug on the low-pressure lubricating oil cavity of the front seal. After 30-45 minutes, check and confirm that the ⅢS seal ring of the stern shaft rear seal and the Ⅳ seal ring of the stern shaft front seal have no oil leakage, and the stern shaft lubricating oil cavity pressure oil is completed. Rudder rear seal pressure oil: The rear seal oil tank is used to pressurize the high-pressure lubricating oil cavity of the rear seal to check and confirm that the Ⅲ seal ring of the stern shaft rear seal has no oil leakage. Then, the rear seal oil tank is used to pressurize the air cavity of the rear seal to check and confirm that the Ⅰ and Ⅱ seal rings of the stern shaft rear seal have no oil leakage. Rudder front seal pressure oil:

2. The stern shaft seal pressure test method according to claim 1, characterized in that, The front seal oil tank is used to pressurize the low-pressure lubricating oil cavity of the front seal to check and confirm that the gap between the front seal and the stern shaft has no oil leakage. When the stern shaft rear seal is pressurized, the rear seal oil tank is used to pressurize the high-pressure lubricating oil cavity of the rear seal to check and confirm that the Ⅲ seal ring of the stern shaft rear seal has no oil leakage. The specific steps are as follows: First, add oil to the rear seal oil tank, and check whether the connecting pipeline between the rear seal oil tank and the stern shaft leaks. After 15-30 minutes, open the valve on the first rear seal oil pipe, pressurize the high-pressure lubricating oil cavity between the Ⅲ and ⅢS seal rings of the stern shaft rear seal, and at the same time, open the plug on the top of the high-pressure lubricating oil cavity. When oil overflows from the top of the high-pressure lubricating oil cavity, tighten the plug again. When pressurizing the high-pressure lubricating oil cavity, the oil in the rear seal oil tank decreases. After the oil stabilizes, continue to add oil to the rear seal oil tank. When the oil amount in the rear seal oil tank reaches the set value, open the plug on the air cavity between the Ⅱ and Ⅲ seal rings of the stern shaft rear seal.

3. The stern shaft seal pressure test method according to claim 1, characterized in that, After 30-45 minutes, check and confirm that the Ⅲ seal ring of the stern shaft rear seal has no oil leakage. When the stern shaft rear seal is pressurized, the rear seal oil tank is used to pressurize the air cavity of the rear seal to check and confirm that the Ⅰ and Ⅱ seal rings of the stern shaft rear seal have no oil leakage. The specific steps are as follows: Open the valve on the second rear seal oil pipe, pressurize the air cavity between the Ⅱ and Ⅲ seal rings, and at the same time, open the plug on the top of the air cavity. When oil overflows from the top of the air cavity, tighten the plug again.

4. The stern shaft seal pressure test method according to claim 1, characterized by When pressurizing the air cavity, the oil in the rear seal oil tank decreases. After the oil stabilizes, continue to add oil to the rear seal oil tank. When the oil amount in the rear seal oil tank reaches the set value, open the plug on the normal-pressure cavity between the Ⅰ and Ⅱ seal rings of the stern shaft rear seal. When oil overflows from the top of the normal-pressure cavity, tighten the plug again, and check and confirm that the Ⅰ and Ⅱ seal rings of the stern shaft rear seal have no oil leakage. The specific steps of the stern shaft front seal pressure oil are as follows: First, the oil is added to the front seal oil tank, and when the oil in the front seal oil tank reaches the set value, the plug on the low-pressure oil chamber between the front seal No. IV and No. V is opened. When the oil overflows from the top of the low-pressure oil chamber, the plug is tightened again; After 30-45 minutes, check and confirm that there is no oil leakage between the front seal outside and the gap between the front seal and the propeller shaft.

5. The stern shaft seal pressure test method according to claim 1, characterized by When the propeller shaft lubricating oil chamber is pressurized, the propeller shaft rear seal is pressurized, and the propeller shaft rear front seal is pressurized, a small amount of oil leakage is allowed, and the maximum allowable leakage of oil leakage is not more than 0.5 liters per 3 hours.

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