when does a gramophone face need re-machining?
when does a gramophone face need re-machining?
(OP)
Hi Guys, just came across a 16" Class 600 expanding gate valve, and there doesn't appear to be much gramophone face on there at all.
Maybe it was never very deep, i don't know. But the finish on the face is certainly not to the specs i have.
My drawings specify 45 - 50 serrations per inch.
Are there any standards to check so that i can tell when a gramophone finish needs re-machining?
Thanks
Maybe it was never very deep, i don't know. But the finish on the face is certainly not to the specs i have.
My drawings specify 45 - 50 serrations per inch.
Are there any standards to check so that i can tell when a gramophone finish needs re-machining?
Thanks





RE: when does a gramophone face need re-machining?
The purpose of the serrating is of course, togheter with the flange sealing material, to ensure the correct geometric compression and sealing between the flange and counter-flange surfaces.
Advice: first check that you have the complete and correct description of valveflange (serrated or flat), sealing type (gasket or o-ring), and counterflange (serrated, flat or flat with groove for o-ring) and complete norm description with drawings of details for all parts.
As the valve-flange is only a lesser (but important!) part of the sealing, any modification of the valve-flange will influence the total sealing, and should be done in accordance with the end-users norms and/or wishes.
RE: when does a gramophone face need re-machining?
What gasket is to be used? Operating conditions may dictate a different gasket design or materials.
RE: when does a gramophone face need re-machining?