I. Introduction
It is a good thing that more and more customers are considering to purchase HF welding machine from China;

but it is really said that most of the customers don't know how to choose correct suppliers, then customer's investment plan is heavily affected by lower quality machines or non-trust-worthy suppliers.

When customer's benefits are hurt, some of these victims will blame to be not careful engough;

some of them swear that THEY WILL NEVER BUY "MADE IN CHINA" MACHINE AGAIN.

Actually, no matter how these victims think, most of trust-worthy suppliers are victims too in this battle.

Because the reputation of made in china machines are affected. 

Now, let's work together to share some tips to find really good and trust-worthy suppliers in China.

II. Tips of looking for QUALITY HF welding machines in China

01.  Check the grounding platen position.

The grounding platen should press behind welder head, it is correct way.

It is convenient to feed material, and good way to protect hands of workers from hurt.

02. Check High Frequency Leak

If the supplier said they can move grounding position behind welder head, then try following way.

When machine is working and outputing high frequency, the operator must can touch lower working platen WITHOUT FEELING currency hurt.

If operator feel electricity hurt or feel  a little bit numbing, you should be careful.

This machine is not well processed, the high frequency radiation is leaking;

it will hurt operators body soon or later.

03. Check High Frequency Output Performance.

When machine is output high frequency, you can hold a screw-dirver (the hand hold part must be plastic or isolation design) to kick upper electrode.

there will be spark or flash on the place of electrode that you kicked,  please check the spark or flash carefully;

if spark or flash is small, blue; it means the machine high frequency output is excellent.

Otherwise, it is dangerous if you see spark is BIG .

04.  Check Welding Performance.

Suppose the upper electrode of machine is 1000mm long,

then you ask supplier try a 1000mm long mould,  but try with material plastic 400mm long and thickness about 0.3mm;

right now, the mould is much longer than material, only quality machine can make succesfull welding and with no spark or flash.

But bad quality machines, it can not work at all, because high frequency is not professional processed.

Bad machines get electricity short-circuit, you can image that the gap between mold and working platen is only about 0.3- 0.5mm.

05. Use HF radiation meter to measure RF radiation level.

You'd better test a 25KW or 50KW machine, the radiation level in tesing should reach international standard,

but the best performance is reach European standard which is much lower than international standard.

Why we ask you try to measure 25KW or 50KW machine, it is standard to check supplier capacity.

06.  Check ATS System (Auto-Tuning-System)

The supplier is a good supplier if their machines have ATS System, 

When sealing complex medical pouches, blood bags, urinary bags and similar products, high consistency and repeatability is required. However, this isnt the case with most HF sealing systems using standard oscillator tube HF generators. Their low frequency and harmonics dont allow efficient power coupling; tending to dissipate power, only transferring 30-70% of total power to the load (sealing dies). Aside from the basic inefficiency of the equipment, users also experience excessive down time mainly due to arcs and constant tuning of parameters and system components due to product and die changeovers on the same equipment.

III.    Tips for looking for trust-worthy suppliers in China

How to verify if the supplier is manufacturer of machine, but not a trader and not a copy one?

Answers: Please ask the supplier to show you machine pictures, working videos, even Engineer designed drawing of the machine.

Usually a trader or a copy supplier will not show their company information in working video. Of course, they don't have drawing of machine too.

Moreover, you can come to their factory to see their true face before your eyes.

What else can you find a good & trust-worthy supplier?

Answers:

1. Usually speaking, the manufactuer with longer history will be better than a new manufacturer.

Like HONGHAI, almost 14 years history makes she more trusty-worthy and quality-warranty.

In China, the even life-span a company / factory is only 3 years. You have to consider after sales issues 2 or 3 years later.

2. Choose 2 or more suppliers, and visit their factory one by one, then make final decision.

3. Ask you Chinese friend to check company information, certificate, trust records from Chinese government bureau, custom online data.

Or you can check their website on  http://www.whois.com/