When hydraulic power pack starts, it is in the opposite direction

The oil-in and oil-out of hydraulic power pack are reversed

Replace and reconnect the original oil-in and oil-out

When hydraulic power pack starts, the movable frame moves automatically without key-press

1. The proportional servo valve is stuck by the foreignmatter in hydraulic liquid

2. The control circuit board of proportional servo valve is damaged

3. The hydraulic circuit connect to the proportional servo valve in a wrong way

1. Dismantle valve handle and clean it

2. Change the control circuit board of proportional servo valve

3. Check hydraulic circuit and correct the wrong connected hydraulic circuit

The temperature of hydraulic liquid is excessive high

1.Radiator does not work efficiently

2.  The rest temperature of radiator is set too high

1.Check the auxiliary oil pump and fan to make sure them work

2. Lower the rest temperature of radiator

when use manually operation, the speed of welding machine is  slow before the welding,

1.The temperature of oil in the hydraulic power pack is too low

2.The oil temperature selection of hydraulic power pack is too low

1.Start the hydraulic power pack, after a while , observe the temperature of oil, if the temperature meets the requirement, start to weld

2. Increase the cryo spacing of the temperature detect switch

When operate hydro cylinder, the speed is uneven

There is air in the hydraulic system

Let off little oil, remove the air to make sure the oil does not bubble again

When start welding, there is a extended periods of short causes the rails can not be pull apart   

The action frame strokes to the end, there is no enough excess for back migration

Leave2- 3 millimeter gap when bond the rails

As the time of unsteady flash butt is too long, there is also unsteady flash butt in low-pressure stage  

Feedback current is too little

Increase the setting value of feedback current under high pressure

The temperature of cooling water is excessive high

1.The amount of cooling water in water chiller box is too little

2.The water chiller does not refrigerate

1. Replenish some water to the water level of being specified.

2.Start the refrigeration system of water chiller

Upset allowance is lower than set point

1.The heat input of rail is not enough

2.System pressure is not enough

1.Shorten the cable length from mains transformer to rail  welding machine, or change the welding voltage through autotransformer

2.Increase the system pressure of hydraulic power pack  

The shearing is incomplete, allowance is oversize

1. Change shearing tool, or start to pad by knife-edge

2.  Screw of shearing tool is loose

1.Remove shearing tool, start to pad by using special welding material and clamping fixture

2.Take down the water-cool copper liner of shearing tool, then align shearing tool and tighten retaining bolts

The shearing is incomplete, some welding beading is not sheared off

1.The initial alignment of rail peak is inaccurate

2. The reserved seam of rail peak is excessive

3.The pull-down between action frame and statically determinate is not maximizing

1.The distance between rail peak and shearing tool is about 30mm

2.Adjust the reserved seam of rail peak to 2～3mm

3. Adjust the distance between action frame and statically determinate to the maximum

Oil pipe link leaks oil

1.O sealing ring in joint is damaged

2.Metalwork of  joint is damaged

1.Change O sealing ring

2.Change oil pipe

Water pipe jointing leaks

1.Pipe strap in the connection of water pipe lost effectiveness

2. Rubber of water pipe aging

1.Change pipe strap

2.Change water pipe

Water penetration on electrode

Remove the electrode, inspect to water, then can see water sweating

Change the electrode on the same side, or change the electrode