Boiler installation safety valve work requirements

Meet the following requirements:
(1) A steam boiler with a rated evaporation greater than 0.5 t/h shall be equipped with at least two safety valves; a steam boiler with a rated evaporation less than or equal to 0.5 t/h shall contain at least one safety valve. Separable economizer outlets and steam superheater outlets must be equipped with safety valves.
(2) The safety valve shall be installed vertically in the highest position of boiler drum and header. No outlet pipe and valve for access to steam shall be installed between the safety valve and the drum or header.
(3) The lever-type safety valve shall have means for preventing the hammer from moving by itself and a guide that restricts the derailment of the lever. The spring-type safety valve shall have means for lifting the handle and preventing the adjustment screw from being easily turned.
(4) For boilers with a rated steam pressure less than or equal to 3.82 MPa, the throat diameter of the safety valve should not be less than 25 mm; for boilers with a rated steam pressure greater than 3.82 MPa, the throat diameter of the safety valve should not be less than 20 mm.
(5) The connection pipe between the safety valve and the boiler shall have a cross-sectional area not less than the inlet cross-sectional area of ​​the safety valve. If several safety valves are jointly installed on a short pipe directly connected to the drum, the cross-sectional area of ​​the short pipe shall not be less than 1.25 times the area of ​​all safety valve exhaust steam.
(6) The safety valve should generally be equipped with an exhaust pipe. The exhaust pipe should pass through to a safe location and have sufficient cross-sectional area to ensure that the exhaust is unimpeded. The bottom of the exhaust pipe of the safety valve shall be equipped with a hydrophobic pipe that is connected to a safe place. No valve shall be installed on the exhaust pipe and the drain pipe.

roller screen door

Elegant insect protection roller blind for door

Screwing mounting into the wall.
Long-lasting, sturdy, powder-coated aluminium aluminium profiles
UV-resistant and tear-resistant fiberglass fabric
Smooth rolling of the roller blind in a compact aluminium cassette
Rollo individual, open and close either with two handles 
The ideal solution for various door airing without being disturbed by annoying insects
EN13561-2015 certification:
Resistance to wind load: Class 1
Operating effort: Class 1
Mechanical Endurance: Class 1
Resistance to corrosion: Class 2
As the professional Insect Screen supplier, we cooperated with consumer from all the world to settle the insect problem.

Roller Insect Screen Door

Roller Insect Screen Door,Screen Rolling Tool,Curtain Door,Mosquito Insects Window Screen

Huanghua Techo Building Material Co., Ltd. , http://www.insectsscreen.com