diaphragm valves promote clean production in the pharmaceutical industry and adhere to various regulatory standards
diaphragm valve is one of the most important equipment in the pharmaceutical industry. it is a special type of shut-off valve. its opening and closing member is a diaphragm made of soft material, which can separate the valve body cavity from the bonnet cavity. according to valve experts, diaphragm valves have high frequency use, ultra-pure to heavily polluted grinding media, easy cleaning, good conditioning performance (liquid) and flowable optional biological advantages. of course, diaphragm valves also have disadvantages such as media pressure loss, operating pressure and temperature limits.
visually speaking, the diaphragm valve is actually a “clamped” valve with an elastic diaphragm that is bolted to the compression member and the compression member is operated by the valve stem and moves up and down. as the compression member rises, the diaphragm lifts up and creates a path; as the compression member descends, the diaphragm presses against the valve body (assumed to be a valve)or presses against the bottom of the profile (assuming straight-through). diaphragm valves are more suitable for switching and throttling. in the pharmaceutical industry, they are mainly used in pharmaceutical water.
there are many regulations and directives for diaphragm valves in the world. for example, in the case of aseptic applications, the fda even specifies the use of diaphragm valves to ensure good cleanliness. in terms of eu-gmp standards, diaphragm valves are required to avoid cross-contamination and easy equipment cleaning. therefore, the valvecan be used in applications that are easy to clean, easy to sterilize, self-emptying and cavity filling.
in addition to the diaphragm valve products themselves to comply with the relevant regulations and standards, in the production, storage and distribution of pharmaceutical quality water or ultra-pure steam, also comply with the relevant regulations. in order to ensure the stability and reliability of product quality, the components of pharmaceutical water equipment also have corresponding quality requirements. therefore, various diaphragm valves need to be designed and developed in conjunction with the corresponding pharmaceutical process.
for example, the sealing of the diaphragm valve, the sealing system of the diaphragm valve will directly affect the purity of the product. the author understands that in the traditional sealing system, the valve will seal through the sealing contour on the diaphragm, but in general, the valve body itself has no additional sealing profile. since the diaphragm and the actuator are fixed by bolts, the sealing surface forms an annular gap. the medium penetrates through the closing action and is discharged when the valve is opened, which can cause contamination.
in response to the above situation, some valve companies have developed special sealing methods. it is reported that the valve body and the diaphragm have a sealed profile. this design will greatly reduce the annular clearance when the diaphragm is pressed against the valve body, thereby preventing the entry of the medium and significantly reducing the pumping effect.
although diaphragm valves are widely used in the pharmaceutical industry, customers should pay attention to some things when operating equipment. for example, the diaphragm valve opening pipe network system should not be arbitrarily changed. after the installation is completed and the test conditions are met, all the diaphragm valves are debugged and set using a special intelligent instrument, and the valve opening degrees are locked to make the pipe network achieve the hydraulic working condition balance. . during the normal operation of the pipe network system, do not arbitrarily change the opening degree of the diaphragm valve, especially do not change the opening degree locking device.
also, do not install a shut-off valve . when a loop is repaired, the diaphragm valve on the loop can be closed. at this time, the diaphragm valve acts as a cut-off valve tointercept the water flow, and then returns to the original locked position after the inspection is completed. therefore, if a diaphragm valve is installed, it is no longer necessary to install a shut-off valve.
when the system adds (or cancels) the loop, it needs to be re-commissioned. when adding or removing the loop in the pipe network system, in addition to increasing (or closing) the corresponding diaphragm valve, in principle all new diaphragm valves are added. and the diaphragm valve in the original system loop should be re-commissioned and set (the diaphragm valve in the original loop does not have to be re-adjusted). it is worth mentioning that in air conditioning and heating systems, the hydraulic balance of the water circulation system as the energy distribution is very important.
pharmaceutical water has strict requirements on cleanliness. as a device that is in direct contact with the medium, the diaphragm valve should follow relevant regulations to ensure the purity of the medium. in addition, the relevant enterprises need to combine the pharmaceutical water technology to develop equipment that meets the actual conditions of the industry, thereby helping the pharmaceutical industry to produce cleanerly.