Needle valve is an important part of measuring line system. Mainly include cut-off valve and ball valve, they typically used for open or cut off the pipeline pathways. Needle valve valve core is a very sharp cone, type needle valve type compression ability than other types of valve Stronger, good sealing, so generally used for small flow, high pressure gas or liquid medium sealing.
Ball valve opening and closing by the valve stem, round ball valve axis pipe fittings manufacturer rotation - the movement of the valve, can be used to adjust and control of the fluid. Ball valve in the line is mainly used for cutting, distribution, and change the flow direction of medium, suitable for switch, cut off valve use.
Therefore, the instrument type needle valve and ball valve on the use and function is a big difference.
If the needle valve type oil leakage problems how to deal with?
In place of oil and gas production, below the pressure gauge usually use are the needle valve type, but the production site type needle valve oil leakage phenomenon will occur, the processing method has the following three problems:
1, tighten packing nut;
2, open the packing nut, with raw tape wrapped around the valve stem;
3, open the packing nut, remove the packing gland ring, push the new packing.
Hope that we can regularly check the type of needle valve, the packing nut in leak detection, if there is a problem to handle in time.
Common stem head shape to blunt the valve stem, stem head into the category of quick opening type, because of the rapid increase in traffic after opening. General installation in fluid off. Seat in the middle of the tube fitting manufacturer commonly used plastic and metal seal.
System in other occasions of fluid is corrosive or erosion resistance, high temperature and high pressure at the same time in order to improve the rod head in the face of have a high temperature adhesive wear and erosion wear and corrosion resistance, resistance of the general material selection will drill stem head base alloy,
Increase the use time of valve.
Non-rotating stem head design, is to eliminate Chu stem head and valve seat wear and scuffing, needle valve type non-rotating stem head design structure and part of the stem head.
Using similar threads in the valve stem drive and the activity of joint connection installation, to ensure that when the valve is closed, the valve stem head stem head can do when in contact with a straight up and down movement, does not lead to wear and the rotation of the bite - movement. In the meter needle Type valve often switch in the workplace, often will adopt the structure of the valve stem.
To type needle valve what problem should consider when select material?
To the needle valve type selection is anticorrosive problem, we first need to consider when this is very important, because will affect the normal use, its corrosion is mainly relative to the body, it USES the material is stainless steel or carbon steel, etc., although the corrosion Material has a lot of, but it was hard to choose a very appropriate, because 14 tube fitting the problem of corrosion is very complex and difficult.
In the needle valve selection when there are a lot of difficulties, not only took into account the characteristics of anti-corrosion and at the same time also need to consider pressure and high temperature resistant ability. Under the condition of the pressure and temperature is not high, using non-metallic make the material of the valve body, often can be With effective anti-corrosion, type needle valve body outer surface also by atmospheric corrosion, usually applied paint to give protection.