4、其他

阀门垫圈泄漏：主要原因是不耐侵蚀，不适应工作温度和工作压力；还有高温阀门的温度变化。预防方法：采用与工作前提相适应的垫圈，对新阀门要检查垫圈材质是否适合，如不适合就应更换。对于高温阀门，要在使用时再紧一遍螺栓。

 

阀门阀体开裂：一般冰冻造成的。天冷时，阀门要有保温伴热措施，否则停产后应将阀门及连接管路中的水排干净（如有阀底丝堵，可打开丝堵排水）。

手轮损坏：撞击或长杠杆猛力操纵所致。只要操纵职员和其他有关职员留意，便可避免。

 

阀门填料压盖断裂：压紧填料时用力不平均，或压盖（一般是铸铁）出缺陷。压紧填料，要对称地旋转螺丝，不可偏歪。制造时不仅要留意大件和枢纽件，也要留意压盖之类次要件，否则影响使用。

阀杆与阀板连接失灵：闸阀采用阀杆长方头与闸板T形槽连接的形式较多，T形槽内有时不加工，因此使阀杆长方头磨损较快。主要从制造方面来解决。但使用单位也可对T形槽进行补加工，让它有一定的光洁度。

 

Common fault in the valve repair solution

Maintenance personnel of the valve, the valve production process must have a basic valve repair knowledge, the conventional valve damage to timely maintenance and prevention, the following are some common valve troubleshooting approaches and methods of prevention

1, stuffing box leakage

Run, run, drip, the main aspects of leakage, we often see in the factory.

 A stuffing box leakage causes the following:

① filler and the erosion of media, temperature, pressure incompatible; ② The loading method differences error, circled the entire root filler into the most vulnerable to leakage; ③ stem machining accuracy or surface finish is not enough, or ellipticity or nicks; ④ The stem pitting, or rust due to lack of protection of the open air; ⑤ The stem bending; ⑥ The filling materials used for too long has been aging; ⑦ manipulation is too fierce.

Eliminating packing leakage is: (1) accurate selection of the filler; ② According to the accurate filling; ③ The stem cells processing differences, to repair or replace, surface finish, minimum ▽ 5, more important, to achieve more than ▽ 8, and no other defects; ④ to take protective measures to prevent corrosion, has been to replace the corroded; to ⑤ stem bending straightening or update; the ⑥ filling materials used by a certain time, to be replaced; ⑦ manipulation to pay attention to a smooth, slow to open slow off to prevent drastic changes in temperature or medium impact.

2, closed pieces of leakage

Usually the stuffing box leak is called leakage, called the closed parts within the vent. Closed leak, the valve inside, not easy to find.

Closed pieces of leakage can be divided into two categories: one is the sealing surface leakage, and the other seals roots leak.

Causes of leakage are: ① sealing surface grinding; ② ring with the valve seat, the valve with Qi Yan; ③ valve flap and valve stem is not strong *; (4) stem bending and torsion, so that the upper and lower closed pieces of differences error; ⑤ closed too fast, bad or has already damaged sealing surface contact; ⑥ The choice of materials properly, and withstood the erosion of live media; ⑦ globe valve, gate valve for regulating valve. Sealing surface to withstand the erosion of the live high-speed active medium; to ⑧ some media, the valve is closed gradually cooled, so that the sealing surface float to the surface of the slit will produce erosion phenomenon; to ⑨ some of the sealing surface and the valve seat, valve valve threaded connection between the easily produce the oxygen concentration cell, erosion loose; ⑩ welding slag, rust, dust and other impurities embedded in, or produced in the system blocking all mechanical parts off the spool, so that the valve can not be locked.

 

The precautionary approach:

 (1) prior to use necessary to really try to pressure leak testing and found that the sealing surface leakage or roots seals leak, properly handle before use; ② The advance check valve of the various components is intact, stem bending and torsion can not be used or the valves and valve stem connect the valve can not be *; (3) the valve off the critical steady strength, not to Meng Jin, such as bad or block hinder contact between the sealing surface, should immediately open a little, so that the debris outflow, and then carefully closed; ④ the selection of the valve, not only to consider the corrosion resistance of the body, but also to consider the closed parts of erosion resistance; ⑤ The structural characteristics in accordance with the valve, the use of accurate parts need to adjust the flow control valve; ⑥ The for off the cooling medium and large temperature difference between the situation after the valve in the cooling and then the valve is closed; ⑦ valve seats, valve and seal threaded connections, Teflon belt threaded between the filler, so that The exclusion does not idle; the ⑧ may fall into the valve of impurities, the filter should be added in front of the valve.

 

3, the valve stem down failure

Stem down failure reasons: to ① manipulate excessive thread injury; ② The lack of lubrication or lubricant failure; (3) stem bending and torsion; (4) surface finish is not enough; the ⑤ tolerances are not allowed to bite too tight; ⑥ stem nut tilt; ⑦ improper choice of materials, such as stem and stem nut for the unification of material, easily bite; ⑧ thread media erosion (refers to the dark bar valve or valve stem nut in the lower); the ⑨ open valve the lack of protection. stem threads are covered with dust and sand, or rain frost by corrosion.

 

Prevention methods:

(1) carefully manipulate closed when not to Meng Jin, and not open to the top dead center, open enough after the hand wheel to reverse a twice, so that the thread on the side of the seal in order to avoid the media to promote the stem upward impact; ② often check the lubrication to maintain a normal state of lubrication; ③ Do not use a long lever opening and closing valves, workers accustomed to using a short lever to strictly control the force measured, to prevent twisting bend the stem (refer to the hand wheel and stem directly connected to the valve); ④ The progress processing or repair quality to achieve regulatory requirements; to ⑤ material to be resistant to erosion, to adapt to temperature and other works on the premise; the ⑥ stem nuts not to use the same with the stem material; and the ⑦ plastic for stem nut, checking strength, can not consider only the good corrosion resistance and low coefficient of friction must also consider the strength of the subject, strong enough, do not use; ⑧ open valve and stem protection; ⑨ normally open valve, hand wheel to schedule rolling, so as not to stem rust to live

 

4, other

Valve gasket leak: The main reason is impatience erosion, not suited to working temperature and pressure; high temperature valve temperature. Methods of prevention: A washers compatible and works on the premise, the suitability of the new valve to check the gasket material, such as not suitable to be replaced. Temperature valve, when in use and then tight again bolt.

 

The valve body cracking: general freezing caused. Cold weather, the valve must have insulation with thermal measures, otherwise should be discontinued after valve and connecting pipe in the water row clean (if any valve bottom plugs, open wire blocking the drainage).

Hand wheel damage: impact or a long lever manipulation violently due. Handling staff and other relevant staff to pay attention, could have been prevented.

 

Valve packing gland rupture: compression packing force is not the average, or gland (usually cast iron) defect. Compression packing to symmetrically rotating screws, non-skew. Must not only pay attention to large and hub parts manufacture, but also pay attention to like sub-elements of the gland, or affect the use.

Connection of the stem and the valve plate failure: valve stem rectangular head and ram T-shaped slot connection in the form of more T-shaped slot is sometimes not processing, so to stem the rectangular head wear out sooner. Mainly from manufacturing to resolve. And use T-shaped slots make up processing, it has a certain finish.