Heavy Weight Rams – Kit #9181-34W
For press welders with dead weight over 50 pounds
- Factory pre-plumbed for fast installation
- Includes all components and interconnecting tubing
- Reduces electrode force below ram dead weight
Reduce Electrode Force Until Safe – OSHA-Compliant Protection for Resistance Welders
Unitrol Electronics offers SOFT TOUCH, a spot welder safety system now standard on all 9180 series SOLUTION welding controls at no extra cost. This fully passive system maintains low electrode force until it’s safe to apply full welding pressure, protecting operators from pinch point injuries.
Key Benefits
- No operator adjustments required – fully passive safety system
- Works with electrode changes – no recalibration needed
- OSHA-compliant – meets 1910.255(b)(4) and 1910.217 standards
- Fail-safe operation – prevents electrode movement if sensors detect faults
- Retrofit available – can upgrade any existing controls
How SOFT TOUCH Spot Welder Safety Works
After initiation, electrodes close under low force (40 lbs or less, even on heavy press welders). The Unitrol TOUCH SENSOR system detects when electrodes contact metal. If an obstruction is detected before closing, electrodes return to the fully open position.
No adjustment needed when changing welding force or electrode spacing.
Safety Sequence
- Low-force closure – electrodes advance under minimal pressure
- Metal detection – electronic sensors confirm proper part placement
- Obstruction response – electrodes retract if no metal detected within set time
- Full force application – welding pressure applied only when safe
Fail-Safe Protection
- Sensor fault detection – electrodes won’t move if sensor is already closed at initiation
- Disconnection protection – electrodes close under low force then return after field-settable delay (1-99 cycles)
- Visual feedback – display shows which sensor input caused fault
SOFT TOUCH Kit Options for Resistance Welders
SOFT TOUCH requires a 5-way externally piloted solenoid valve, shuttle valve, and precision pressure regulator added to existing 4-way valves. Unitrol offers three pre-plumbed kits:
Light Weight Rams – Kit #9181-34Y
For press welders under 50 pounds or rocker arm welders
- Ideal for rams that don’t drop by gravity
- Complete pre-plumbed kit
- Suitable for rocker arm applications
Light Weight Gravity-Drop Rams – Kit #9181-34H
For press welders under 50 pounds that drop smoothly by gravity
- Optimized for gravity-assisted electrode movement
- Pre-plumbed installation kit
- All necessary components included
Optional Redundant Sensor
Add your own proximity switch or LVD system (closes when electrodes are less than ¼” apart) for additional protection. Useful when welding non-flat parts that require electrode compression.
Why Spot Welder Safety Matters: A Real OSHA Case Study
The Problem
A manufacturer with multiple Unitrol SOLUTION controls faced OSHA closure threats after two welding department accidents within two months. Operators had to hold parts close to electrodes, putting fingers at risk.
Failed Solutions
- Light curtains – Operators needed access to the electrode zone during welding
- Ring guards – OSHA rejected as “easily defeated” and dependent on mechanical adjustment
OSHA Requirements
The inspector demanded a fully passive system that:
- Requires no operator settings or adjustments
- Continues working after electrode changes or spacing adjustments
- Cannot be defeated or bypassed by operators
The SOFT TOUCH Solution
Unitrol developed an electronic sensing system integrated directly into the SOLUTION welding control. The system uses electronic signals rather than mechanical switches, creating a truly passive safety solution.
Result: After installing SOFT TOUCH on one welder, the system cleared OSHA inspection. The company installed 22 systems and returned to full 3-shift production.
OSHA Compliance for Resistance Welding Safety
SOFT TOUCH meets multiple OSHA standards for machine guarding and resistance welding equipment:
1910.212(a) – Machine Guarding
Provides electronic safety device protection for operators and employees in the machine area from pinch point hazards.
1910.255(b)(4) – Resistance Welding Machines
Guards press welding operations where operators’ fingers could be under the point of operation, using electronic sensing similar to requirements for punch press operations.
1910.217(c)(3) – Presence Sensing Devices
The electrode acts as the sensor, detecting metal presence before applying high force. System prevents stroke initiation if sensors detect faults and displays failure indicators.
Technical Specifications
Control Compatibility: Unitrol 9180 series SOLUTION controls only (cannot be installed on other welding control brands)
Installation Package:
- Padlockable NEMA-12 enclosure with precision pressure components
- Specialty valves for existing solenoid valve integration
- All mounting hardware and pneumatic tubing
- Installation instructions
Applications:
- Press welders (all weight ranges)
- Rocker arm welders
- Transguns
- Multi-spot welding systems
Force Settings: Field-adjustable with lockable settings to maintain force below injury threshold.
Frequently Asked Questions
Can SOFT TOUCH be installed on any welding control?
Yes, UNITROL Soft Touch safety systems can be installed on almost all new and existing resistance welders, regardless of the brand of the welding control
Do operators need to adjust SOFT TOUCH settings?
No. The system is fully passive with no operator adjustments required. All settings are lockable and contained in a padlockable NEMA-12 enclosure.
What happens if the sensor fails?
The system is fail-safe. If sensors are faulty at initiation, electrodes won’t move. If sensors disconnect during operation, electrodes close under low force and return after a preset delay.
Does SOFT TOUCH slow down production?
No. The low-force electrode advance and metal detection occur in milliseconds, adding minimal time to the welding cycle.
Will SOFT TOUCH work after changing electrodes or spacing?
Yes. The system automatically adapts to electrode changes and spacing adjustments without recalibration or settings changes.
Contact Spotwelding Solutions for SOFT TOUCH Installation
Ready to protect your operators and satisfy OSHA requirements?
Our Dallas-based team provides expert SOFT TOUCH consultation, installation, and service throughout North Texas. Whether you need a single retrofit or facility-wide safety upgrades, we deliver solutions that work.
Distributor Support: Your authorized Unitrol distributor can help size a SOLUTION control with SOFT TOUCH for any spot welding application.
