FDS -622 VALVE PACKING SET

Transcription

1 Certified, patented, patent pending Low-Emission Seal packing Technology has been developed for last 10 years, guarantee leak <100 ppmv and 50 ppmv for 5 years or 5000 cycles FDS -622 VALVE PACKING SET This disrupt US techonlogy aims at the heart of the emission problem which nobody ever clearly defines or understands. The innovation not only saves the planet, but also keeps air clean, and you healthy and safe. Fluid Dyamics System LLC Winston, GA 30187, USA

2 Why manually operated gate valves have the highest stem leakage among the valves, why API 622 packing test cannot guarantee your valve to meet fugitive emission standard, Why API 624 cannot guarantee your rising stem valve to meet to meet fugitive emission standard for five years, Why API 642 cannot guarantee your part-turn valves to meet to meet fugitive emission standard for five years, but FDS Low Emission packing set can!!! Part I. What 1. Dynamic seal vs. Static seal Dynamic seals prevent leaks by (a) filling gaps (FIG.1 )and (b) holding pressures between relatively moving surfaces, while static seals prevent leaks by(a) filling gaps (FIG.1) and holding pressures between stationary surfaces, so no gaps, no leaks, no pressure difference, no leaks, all valve stems seals are dynamics seals 2. Dynamics sealing mechanism Dynamic seal machines include two basic seal elements, radial geometry conformation and axial geometry conformation and a combination of the two, the axial geometry conformation for linear stem is to insure that the cross section profiles between travel distances should be the same or very closed even they are not round (FIG.2), the seal band is 2D, while the radial geometry conformation for the rotary stem is to insure the cross section profiles between rotary moving surfaces at any angle should be the same or round but any two cross sections can be different in sizes (FIG.3), the combination of linear stem and rotary stem becomes the helical stem ( like gate valve stem), any two cross section profiles must be the same and round (FIG.4).

3 and stronger materials of the stem, the packing wears out faster than the stem and cause the gap increase. c. Corrosion acceleration counts about 20 % leakage failures, the movement of the stem acts like a mixing for accelerating corrosive chemical reaction and increase the gaps due to new material creation and loss of materials between stem and packing in the chemical reactions. d. Foreign object inclusion counts about 5 % leakage failures, it damage the stem and packing and creates new gaps Part II. Why 1. Why dynamic seals between the stem and packing (FIG.5 ) becomes more challenging than the static seals, because the dynamic seal brings more issues related the gap increase and cause more leakage (T1) a. Dynamic enlargement is caused by offsets and counts 45 % leakage failures, this is why most valve makers never realize the dynamic enlargement is the major factor for causing stem leakage, this is why without load most valves even passing under API 622,242 and 224 still would fail in service 1.1 A translational offset between stem axis and packing axis (FIG. 6) 1.2 A rotational offset between stem axis and packing axis (FIG.7) 1.3 A combination of two offsets has the largest gaps like gate valve stem (FIG.8) b. Wearing counts about 30% leakage failures, because frictions Cause of gaps increase T1 Dynamic enlargment wearing Corrosion accelation Foreign object

4 2. Why helical stem ( gate valve stem ) has the highest leakage, because in order to seal off the helical stem with packing, the cross section A and cross section B should have not only the same profile, but also be round,, moreover the combination of translational and rotational offsets create the largest gaps among all valve stems, the seal band is volumetric, the two conditions must be met for securing helical stem seal, but most API 622 tests are conducted either with linear or rotational actuators, hardly closed to helical stem applications, only few test is equipped with helical actuator. (FIG.10) and push each disc under buckling condition to generate the greatest radial force to push each inner packing against the helical stem among all current live loading devices without repacking or readjustment during 5 years or 5K cycle s life. 2.2 Each of five set of the packing acts at full capacity unlike the current packing in the market with only first three rings with significant capacity; it is the five redundant seals with the highest reliability. Part III. How How to solve four problems and improve the stem seal performances? The FDS-622 stem packing set is the solution (FIG. 9) it includes (a) engaged bearing with (b) four spring pins engaged with the stem with no clearance and five set of packing, each packing has (c) support ring (d) wedge /disc ring, (e) inner packing l (f) external packing 1. Reduce the dynamic enlargement by 1.1 Minimizing the dynamic enlargement with engaged bearing 1.2 Compartmentalizing the packing to small sets for filling gaps with packing and holding pressures with support ring 1.3 Separating static seals with external packing from dynamic seals with inner packing 2. Compensate wearing by inclusive array of stack disc rings with support rings to provide live loading 2.1 An axial compression force is applied to the bearing and each packing between support rings

5 3. Reduce corrosion acceleration by coupling graphite with zinc or zinc plating supports ring (T2), the stem with materials between those two is fully protected. 4. Reduce foreign object inclusion by using the support ring to prevent foreign object from entering each packing set 5. Simplify installation as push /play without calculating torques as long as the packing set below box bore. 6. Comply with VOC and VHAP emissions regulations for repair or replacement 7. Use for manual and automatic valves 8. Meet Consent Decree requirement Part IV. ACT Part Specification Item Stem Size Materials Name in standard Code option Code Bearing " 304 SS SS 2 Spring Pin 316 SS 1 X781 2 Support ring 316 SS 1 Zinc 2 Wedge ring 316 SS 1 X781 2 inner packing Graphite 1 PTFE 2 external packing Graphite 1 PTFE 2 Packing set specifcation Packing material Pressure Temp Remark Class F Graghite Fire Safe 850 Oxidizers small stem 1200 steam PTFE PH 0-14 PTFE+ Graphite Fire Safe Ceramic 1500 F not < 100 ppm Order Form FDS-622 XX YY ZZ EE TT AA LL SS XX OD Stem, YY ID box, ZZ Inner Packing, EE External packing material,tt Support ring, AA wedge ring LL leakage for 5 years,ss Special requirement Fluid Dynamic System LLC 3719 Falls Trail Winston, GA FDS-valve.com sales@fds-valve.com