Description

The metal hard sealing abrasion-resistance ball valve, a distinctive product researched and developed by our company, is applicable for tough working conditions like high impurity, viscosity, temperature and pressure as well as strong corrosion. It adopts reasonable, applicable and high-quality materials, brand-new design concept, advanced production and processing procedures, and whole-process quality control to make every valve satisfied by customers. It has been widely applied In such industries as petrochemical(PE, PP, He-catalytic cracking, cracking, ethylene, synthetic resin, silicon powder, etc.); water drainage of main steam pipeline in power plant; coal powder, deslagging and desulfuration of steel mill; high-pressure melting and slurry filtering system in alumina plant; and coking coal to oil transfer.

Brand-new Design Concept

1 Our company adopts different valve designs in accordance with different working conditions:

The valve seat and ball sealing surface adopt the metal to metal seal while its ball and seat adopt the special hardening treatment to ensure reliable seal, resistance to high temperature, abrasion and corrosion and a long service life. Its ball and seat are provided with good cutting and self-cleaning functions, applicable for the control over media containing grains and fibers.

2 The seat adopts the plate or compression spring load so that it can avoid the jamming between its ball and seat caused by thermal expansion and cold shrinkage, especially in a state or high or low temperature, in which the flexible seat structure with the automatic compensation function is adopted so that the amount of deformation of its ball and seat can be absorbed by the plate or compression spring, thus it can be opened or closed freely in that state with the reliable seal.

3 Its seat seal can adopt the O-ring, graphite gasket or pretightening graphite seal in accordance with working conditions and temperature; these structure types can be adopted reasonably in accordance with actual working conditions to get a satisfactory result. Our hard sealing fixed ball valve adopts the pre-ball seal structure generally with double block and bleed functions (DBB structure) (see the above Instructions for fixed ball valve for specific principle and structure). Generally the floating ball valve adopts the post-ball seat seal structure, which is a kind of one-way seal structure; the floating double-way seal structure can also be adopted in case of special requirements by users.

4 The stem seal of hard sealing ball valve adopts the flexible graphite packing while the flange adopts the flexible graphite with stainless steel wire or the metal twisted graphite gasket, thus boasting the functions of intrinsic safety for fire (conforming to AP1607) and electrostatic prevention (conforming to API607). It adopts the bottom-mounting and blowout-proof structure so as to avoid the blowout of stem caused by the valve misoperation.

Advanced Manufacturing Process

1. Supersonic Flame Spray Coating Process

Its ball surface adopts the surface heat spray coating plant-high velocity oxy-fuel(HVOF), whose process is: after the hydrogen and oxygen gases burn-fully and explode, the high-velocity flame, as high as 6,000 yards/s(triple velocity of sound), will be generated; then the metal powder particles (material selected in accordance with customer requirements) will be sprayed and coated on the ball surface and the seat sealing surface by means of a specially designed spraying gun to form a compact and very adhesive coating with a normal cohesive strength up to 70MPa and a maximum coating surface hardness up to HRC62-70, which is invulnerable to being scuffed by media or impurities in them. HVOF can make a perfect combination between hardness and strength, invulnerable to temperature effects.

2. Paired Precision Grinding Process

Our company can ensure the paired precision grinding between the ball and the seat of every valve. Due to a high solidity ratio between the valves ball and seat, we adopt the unique grinding material, process and assembly to grind on the modified precision grinder with the zero-leakage sealing effect. We adopt the manual grinding mode for large-bore valves so that the quality of every valve can be ensured.

3. High-quality Sealing Material

It is on important factor for ensuring the valve operating performance to adopt the high-quality and reasonable seat sealing material. However, its characteristics can only be given play to on the premise of ensuring to understanding the working conditions and the medium. Therefore, we divide the hard sealing ball valve into four types according to our many years of supply experience and working places. See the applicable places for details.