As per API 682/ISO21049, piping plan 62 is a common plan to improve the environment on
the atmospheric side of single seals by quenching with steam.
Steam quenching is essential for long seal life and safety for high temperature and heavy
hydrocarbon duties. It prevents coke formation, helps to cool the seal at high temperatures
and heats the seal faces on some medium temperature hydrocarbon residue duties.
Provision of dry steam flow at pressure below 1 bar g. is not a simple task; over
pressurization will cause early seal failure. Steam traps and insulation are also essential.
Site surveys often find flow of tepid water to the seal flash off in to steam in a dramatic
fashion causing pressure pulsation at seal.
• In pumps are used to circulate the hydrocarbon fluid to different tanks, drums &
reservoirs which are at high temp. All pumps are critical for the operation of the plant.
• Dry and saturated steam is required to quench the pump seal, so that seal doesn’t fail
due to thermal expansion.
Pumps face the most problems because of seal failures associated with inadequate, or non-
existent steam quench.
Requirement of quenching steam in the pumps according API mechanical seal piping plan # 62
• To prevent solids build up on atmospheric side of seal.
• To prevent icing.
• To cool the product we are sealing.
• To dilute any leakage that might migrate across the seal faces. To introduce low-
pressure steam behind the seal to put out a fire.
To prevent condensate carryover and thereby failure of seals , due to incorrect trap installation
and routing steam should be dry saturated before being utilised. A self-acting pressure
reducing valve and moisture separator in a single module in the quenching steam supply line
ensures dry saturated steam supply at precise pressure to meet API norms. This also enables
the condensate deposited in the drain pocket to be easily removed through the trap.
• Easy to operate and maintain
• Precise control of pressure and temperature
• Ensures dry steam to pump seal
• Proper cleaning of atmospheric side of seal
• Enhanced reliability of operation
• Improved housekeeping
• Reduced cost of ownership