YFL Check Valves Operation and Maintenance Manual

1. General

Thanks for your selection of YFL check valve. As a type of pressure equipment, valve has potential hazards of pressure resulting from leakage of process fluid. For the safety purpose, user shall read this instruction to know what YFL has already taken into account in our design and manufacture, and what action shall be taken by user according to essential health and safety requirements of European Directive 97/23/EC(PED) .

2. Essential health & safety requirements of PED

2.1 What’s YFL design idea

-Check valve are designed as standard product, no consideration of each specific service condition since its too wide.
-Check valve is designed to BS1868, API 6D, valve has adequate strength according to ASME B16.34 pressure-temperature rating. The check valve was EC-type approved by European Notified Body.
-Valve has different sealing materials in accordance with BS1868, API 6D which are corrosion/wear resistance to certain type of fluid.

2.2 What action user shall taken

2.2.1 General
2.2.1.1 In any occurrence, first ensure personnel safety.
2.2.1.2 Use the valves in accordance with ASME B16.34 pressure-temperature rating.
2.2.1.3 Make sure that the selected valve materials are corrosion/wear resistance to the service fluid.
2.2.1.4 Where the service fluid is flammable/explosive, to limit the working temperature.
2.2.1.5 When performing Repair/maintenance operations, make sure that the valves are always depressurized, vented and drained.
2.2.1.6 When performing Repair/maintenance operations, always use appropriate protection e.g. protective clothing, (oxygen) masks, gloves, etc.
2.2.1.7 When performing Repair/maintenance operations, do not smoke, do not use any portable no-Ex-proof electrical device in the area and do not use open fire without a valid work permit.
2.2.1.8 Valve must periodically checked on:
-Tightness of bolted connection (body/bonnet, flange connection).
-Corrosion/wear damages (crack, pitting, thickness of the valve).

3. Working Principle and Structure Description

3.1 Working principle

This serial is sole direction check valve, when fluid flows at normal direction, the disc opens to fluid pressure; when fluid flows converse, the disc closes to the gravity and converse fluid pressure and cut off the bore.

3.2 Structure description

3.2.1 Flange end or but welding end may be selected as to purchaser optimum.
3.2.2 Valves use a reinforced flexible graphite gasket or spiral wound gasket. ..
3.2.3 The 50 bevel seal is used for the valve and the seal material is applied to API 600 or to the customer requirements.

4. Valve Transportation

4.1 Valves are heavy and metal products, care shall be taken to avoid physical injury during transportation. Before transportation, cord and lift device and transportation tool shall be ready, valve package inspected and broken package repaired. Packaging shall conform to specification requirements.
Valve shall be handled with care, no damage the flange end or butt welding end.

4.2 The paint, nameplate and flange sealing surface shall be protected during transportation, no drag valve on the ground especially with the end sealing surface contacted the ground.

4.3 Don't unpack when the valve is not ready for installation at the construction field. The valve shall be placed at a safety location against whether.

5. Servicing

5.1 Where contractually specified, YFL Flow Control Co., Ltd. may provide field installation and adjustment.

5.2 YFL will trace the quality of sold valve and provide service to customer requirements..